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| # DIVISION 550                                                        |
|                                                                       |
| **BRIDGE CONSTRUCTION**                                               |
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## Section 551. --- DRIVEN PILES

Description

**551.01** This work consists of furnishing and driving piles. This work
also includes furnishing and placing reinforcing steel and concrete in
concrete-filled steel shell and concrete-filled pipe piles.

Piles are designated as steel H-piles, concrete-filled steel shell
piles, concrete-filled pipe piles, precast concrete piles, prestressed
concrete piles, sheet piles, or timber piles. Pile load tests are
designated as static or dynamic.

Material

**551.02** Conform to the following Sections and Subsections:

Concrete piles 715.03

Grout 725.22(b)

Paint 708

Pile shoes 715.08

Reinforcing steel 709.01

Sheet piles 715.07

Splices 715.09

Steel H-piles 715.06

Steel pipes 715.05

Steel shells 715.04

Structural concrete 552

Treated timber piles 715.02

Untreated timber piles 715.01

Construction Requirements

**551.03 Pile Driving Equipment.** Furnish equipment meeting the
following requirements.

**(a) Pile hammers.**

**(1) Gravity hammers.** Gravity hammers may only be used to drive
timber piles. Furnish a hammer with a ram weighing between 2,000 and
3,500 pounds and limit the drop height to 15 feet. The ram mass shall be
greater than the combined mass of the drive head and pile. Provide
hammer guides to ensure concentric impact on the drive head.

**(2) Open-end diesel hammers.** Equip open-end (single acting) diesel
hammers with a device, such as rings on the ram or a scale (jump stick)
extending above the ram cylinder, to permit visual determination of
hammer stroke. Submit a chart from the hammer manufacturer equating
stroke and blows per minute for the hammer to be used. A speed versus
stroke calibration may be used if approved.

**(3) Closed-end diesel hammers**. Submit a chart, calibrated to actual
hammer performance within 90 days of use, equating bounce chamber
pressure to either equivalent energy or stroke for the hammer to be
used. Equip hammers with a dial gauge for measuring pressure in the
bounce chamber. Make the gauge readable from ground level. Calibrate the
dial gauge to allow for losses in the gauge hose. Verify the accuracy of
the calibrated dial gauge during driving operations by ensuring that
cylinder lift occurs when bounce chamber pressure is consistent with the
maximum energy given in the hammer specifications. Do not use closed-end
diesel hammers that do not attain cylinder lift at the maximum
energy-bounce chamber pressure relationship given in the hammer
specification.

**(4) Air or steam hammers**. Furnish plant and equipment for steam and
air hammers with sufficient capacity to maintain the volume and pressure
specified by the hammer manufacturer. Equip the hammer with accurate
pressure gauges that are easily accessible. Use a hammer with the mass
of the striking parts equal to or greater than one third the combined
mass of the driving head and pile. The combined mass shall be at least
2,750 pounds.

Measure inlet pressures for double-acting and differential-acting air or
stream hammers with a needle gauge at the head of the hammer when
driving test piles. If required, also measure inlet pressures when
driving production piles. A pressure versus speed calibration may be
developed for specific driving conditions at the project as an
alternative to periodic measurements with a needle gauge.

**(5) Nonimpact hammers.** Use nonimpact hammers, such as vibratory
hammers, only when permitted in writing or when specified in the
contract. If permitted, use such equipment for installing production
piles only after the pile tip elevation or embedment length for safe
support of the pile load is established by static or dynamic load
testing. Control the installation of production piles when using
vibratory hammers by power consumption, rate of penetration, specified
tip elevation, or other acceptable methods that ensure the required pile
load capacity is obtained. On one out of every 10 piles driven, strike
with an impact hammer of suitable energy to verify the required pile
capacity is obtained.

**(6) Hydraulic hammers.** Provide a power plant for hydraulic hammers
with sufficient capacity to maintain the volume and pressure, specified
by the manufacturer, at the hammer under working conditions. Equip the
power plant and equipment with accurate pressure gauges that are easily
accessible to the CO.

**(b) Approval of pile-driving equipment.** Furnish pile-driving
equipment of such size that the permanent piles can be driven with
reasonable effort to the required lengths without damage.

Approval of pile-driving equipment will be based on a wave equation
analysis unless the contract specifies the dynamic formula to determine
the ultimate driven pile capacity. If the contract specifies the dynamic
formula, approval of pile-driving equipment will be based on minimum
hammer energy in Table 551-1. The CO will evaluate the proposed
equipment and accept or reject the driving system within 14 days of
receipt of the pile and driving equipment information.

Use only the approved equipment during pile-driving operations. Approval
of the pile‑driving system is specific to the equipment submitted. If
the proposed equipment is modified or replaced, re-evaluate and resubmit
the analysis and revised data for approval before using. The CO will
accept or reject the revised driving system within 14 days of receipt of
the revised submittal. Approval of a pile hammer does not relieve the
Contractor of responsibility for piles damaged due to driving stress.

**(1) Equipment submittal.** Submit the following pile-driving equipment
information to the CO at least 30 days before driving piles. Include a
wave equation analysis for the proposed pile driving system, unless the
contract specifies the use of the dynamic formula to determine the
ultimate driven pile capacity. Use a professional engineer with at least
3 years experience in wave equation analyses to perform the wave
equation analysis. Submit a resume of the engineer for approval.

*(a) General.* Project and structure identification, pile-driving
contractor or subcontractor, and auxiliary methods of installation such
as jetting or preboring and the type and use of the equipment.

*(b) Hammer.* Manufacturer, model, type, serial number, rated energy
( \_\_\_\_\_ at \_\_\_\_\_ length of stroke), and modifications.

*(c) Capblock (hammer cushion).* Material, thickness, area, modulus of
elasticity (E), and coefficient of restitution (e).

*(d) Pile cap.* Helmet mass, bonnet mass, anvil block mass, and
drivehead mass.

*(e) Pile cushion.* Material, thickness, area, modulus of elasticity
(E), and coefficient of restitution (e).

*(f) Pile.* Pile type, length (in leads), mass per foot, wall thickness,
taper, cross-sectional area, design pile capacity, description of
splice, and tip treatment description.

**(2) Wave equation.** The required number of hammer blows indicated by
the wave equation at the ultimate pile capacity shall be between 3 and
10 per inch.

Use the following hammer efficiencies in the wave equation analysis
unless more specific hammer efficiency information is available:

  ------------------------------------- ---------------------------------
  **Hammer Type**                       **Efficiency in Percent**

  Single acting air/stream              67

  Double acting air/stream              50

  Diesel                                72
  ------------------------------------- ---------------------------------

In addition, the pile stresses resulting from the wave equation analysis
shall not exceed the values at which pile damage is impending. The point
of impending damage is defined for steel, concrete, and timber piles as
follows.

*(a) Steel piles.* Limit the compressive driving stress to 90 percent of
the yield stress of the pile material.

*(b) Concrete piles.* Limit the tensile (*TS*) and compressive (*CS*)
driving stresses to:

*TS* 3*f*~c~\'^1/2^ + *EPV*

*CS* 0.85*f*~c~\' - *EPV*

where:

> *f*~c~' = The 28-day design compressive strength of the concrete in
> pounds per square inch
>
> *EPV* = The effective prestress value in pounds per square inch

*(c) Timber piles.* Limit the compressive driving stress to 3 times the
allowable static design stress.

**(3) Minimum hammer energy.** The energy of the driving equipment
submitted for approval, as rated by the manufacturer, shall be at least
the energy specified in Table 551-1 that corresponds to the required
ultimate pile capacity.

Table 551-1

Minimum Pile Hammer Energy

+------------------------------+---------------------------------------+
| **Ultimate Pile Capacity**   | **Minimum Rated Hammer Energy         |
|                              | (foot-pounds)**                       |
| **(tons)**                   |                                       |
+------------------------------+---------------------------------------+
| ≤ 90                         | 10,300                                |
+------------------------------+---------------------------------------+
| 150                          | 15,600                                |
+------------------------------+---------------------------------------+
| 180                          | 20,700                                |
+------------------------------+---------------------------------------+
| 210                          | 26,500                                |
+------------------------------+---------------------------------------+
| 240                          | 33,100                                |
+------------------------------+---------------------------------------+
| 270                          | 40,100                                |
+------------------------------+---------------------------------------+
| \> 270                       | Wave equation required                |
+------------------------------+---------------------------------------+

**(c) Driving appurtenances.**

**(1) Hammer cushion.** Equip all impact pile-driving equipment, except
gravity hammers, with a suitable thickness of hammer cushion material to
prevent damage to the hammer or pile and to ensure uniform driving
behavior. Fabricate hammer cushions from durable, manufactured material
according to the hammer manufacturer\'s recommendations. Do not use
wood, wire rope, or asbestos hammer cushions. Place a striker plate, as
recommended by the hammer manufacturer, on the hammer cushion to ensure
uniform compression of the cushion material. Inspect the hammer cushion
in the presence of the CO when beginning pile driving at each structure
or after each 100 hours of pile driving, whichever is less. Replace the
cushion when its thickness is reduced by more than 25 percent of its
original thickness.

**(2) Pile drive head.** Provide adequate drive heads for impact hammers
and provide appropriate drive heads, mandrels, or other devices for
special piles according to the manufacturer\'s recommendations. Align
the drive head axially with the hammer and pile. Fit the drive head
around the pile head so that transfer of torsional forces is prevented
during driving and proper alignment of hammer and pile is maintained.

**(3) Leads.** Support piles in line and position with leads while
driving. Construct pile driver leads to allow freedom of movement of the
hammer while maintaining axial alignment of the hammer and the pile. Do
not use swinging leads unless permitted in writing or specified in the
contract. When swinging leads are permitted, fit swinging leads with a
pile gate at the bottom of the leads and, in the case of battered piles,
fit with a horizontal brace between the crane and the leads. Adequately
embed leads in the ground or constrain the pile in a structural frame
(template) to maintain proper alignment. Provide leads of sufficient
length that do not require a follower but will permit proper alignment
of battered piles.

**(4) Followers.** Followers are not permitted unless approved in
writing. When followers are permitted, drive the first pile in each bent
or substructure unit and every tenth pile thereafter, full length
without a follower, to verify that adequate pile embedment is being
attained to develop the required ultimate capacity. Provide a follower
of such material and dimensions that will permit the piles to be driven
to the required penetration. Hold and maintain follower and pile in
proper alignment during driving.

**(5) Jetting.** Do not use jetting unless approved in writing. Provide
jetting equipment with sufficient capacity to deliver a consistent
pressure equivalent to at least 100 pounds per square inch at two
3/4-inch jet nozzles. Jet so as not to affect the lateral stability of
the final inplace pile. Remove jet pipes when the pile tip is at least 5
feet above the prescribed tip elevation, and drive the pile to the
required ultimate capacity with an impact hammer. Control, treat if
necessary, and dispose of all jet water in an approved manner.

**(6) Pile cushion.** For concrete piles, use a new pile cushion to
protect the head of each pile. Cut the pile cushion at least
4-inches-thick and to match the cross-section of the pile top. Replace
the pile cushion if it is compressed more than one-half its original
thickness or it begins to burn. For steel and timber piles, protect each
pile with an approved driving cap. Enclose timber piles with approved
collars or bands to prevent splitting or brooming. Replace caps when
damaged. Do not reuse cushions or caps.

**(7) Pile shoes.** When specified, provide shoes to protect the
pile-tip from damage during driving. Fabricate all shoes to snugly fit
the pile tip. For concrete piles, attach the shoe to the pile using
dowels or other approved methods. For steel piles, design and fit the
shoe to the steel shape and weld the shoe to the pile so as not to
stress the web or the flange. For timber piles, carefully shape the tip
to secure an even uniform bearing for the pile shoe. Treat all holes,
cuts, or caps in treated timber piles with 2-brush applications of
creosote-coal tar solution.

**551.04 Pile Lengths.** Furnish piles with sufficient length to obtain
the required penetration and to extend into the pile cap or footing as
indicated on the plans. In addition, increase the length to provide
fresh heading and to provide for the Contractor\'s method of operation.
When test piles are required, furnish piles in the lengths determined by
the test piles.

**551.05 Test Piles.** Install test piles when specified in the
contract. Excavate the ground at the site of each test pile or
production pile to the elevation of the bottom of the footing before the
pile is driven. Furnish test piles longer than the estimated length of
production piles. Drive test piles with the same equipment as the
production piles.

Drive test piles to the required ultimate capacity at the estimated tip
elevation. Allow test piles that do not attain the required ultimate
capacity at the estimated tip elevation to *\"set up\"* for 24 hours
before re-driving. Warm the hammer before re-driving begins by applying
at least 20 blows to another pile. If the required ultimate capacity is
not attained on re-driving, drive a portion or all of the remaining test
pile length, and repeat the *\"set up\"* and re-drive procedure as
directed. Splice and continue driving until the required ultimate pile
capacity is obtained.

Test piles to be used in the completed structure shall conform to the
requirements for production piles. Remove test piles not incorporated in
the completed structure to at least 2 feet below finished grade.

**551.06 Driven Pile Capacity.** Drive piles to the specified
penetration and to the depth necessary to obtain the required ultimate
pile capacity. Splice piles not obtaining the required ultimate capacity
at the ordered length, and drive with an impact hammer until the
required ultimate pile capacity is achieved.

Use the wave equation to determine ultimate pile capacity of the
in-place capacity of the in-place pile.

**(a) Wave equation.** Adequate penetration will be considered to be
obtained when the specified wave equation resistance criteria is
achieved within 5 feet of the designated tip elevation. Drive piles that
do not achieve the specified resistance within these limits to a
penetration determined by the CO.

**(b) Dynamic formula**. Drive the piles to a penetration necessary to
obtain the ultimate pile capacity according to the following formula:

$$R_{u}\  = \ 1\text{.}6\sqrt{\text{eE}}\text{ log}_{\text{10}}(\text{10N})\  - \ 1\text{00}$$

where:

*R~u~* = Ultimate pile capacity in kips

*E* = Manufacturer\'s rated hammer energy in foot·pounds at the ram
stroke observed or measured in the field

*log~10~(10N)* = Logarithm to the base 10 of the quantity 10 multiplied
by *N*

*e* = Hammer efficiency factor

Use: 0.72 for all diesels

> 0.67 for conventional single acting ECH (external combustion hammers),
> including rope driven hammers

0.50 for conventional double acting ECH

> 0.95 for free fall rams or hammers with internally measured impact
> velocities

*N* = Number of hammer blows per inch at final penetration

**(1) Jetted piles.** Determine the inplace ultimate capacity of jetted
piles based on impact hammer blow counts (dynamic formula) after the jet
pipes have been removed. After the pile penetration length necessary to
produce the required ultimate pile capacity has been determined by
impact hammer blow count, install the remaining piles in each group or
in each substructure unit to similar depths with similar methods.
Confirm the required ultimate pile capacity has been achieved by using
the dynamic formula.

**(2) Conditions for dynamic formula.** The dynamic formula is
applicable only if all of the following apply:

*(a)* The hammer is in good condition and operating in a satisfactory
manner;

*(b)* The hammer ram falls freely;

*(c)* A follower is not used; and

*(d)* The head of the pile is not broomed or crushed.

**551.07 Preboring.** Use auguring, wet rotary drilling, or other
approved methods of preboring.

In compacted embankments more than 5 feet deep, prebore the pile hole to
natural ground. Prebore holes 6 inches greater than the diameter of the
pile. For square, rectangular or H piles, make the diameter of the hole
equal to the diagonal of the pile cross-section plus 6 inches.

For piles end-bearing on rock or hardpan, preboring may extend to the
surface of the rock or hardpan. Seat the pile into the end-bearing
strata.

For piles not end-bearing on rock or hardpan, stop preboring at least 5
feet above the estimated pile tip elevation, and drive the pile with an
impact hammer to a penetration which achieves the required ultimate pile
capacity. Prebore holes smaller than the diameter or diagonal of the
pile cross-section while allowing penetration of the pile to the
specified depth.

If the subsurface obstructions such as boulders or rock layers are
encountered, the hole diameter may be increased to the least dimension
adequate for pile installation. After driving is complete, fill all
remaining void space around the pile with sand or other approved
material. Do not use a punch or a spud in lieu of preboring.

Do not impair the capacity of existing piles or the safety or condition
of adjacent structures. If preboring disturbs the capacity of previously
installed piles or structures, restore the required ultimate capacity of
piles and structures by approved methods.

**551.08 Preparation and Driving.** Perform the work under Section 208.
Make the heads of all piles plane and perpendicular to the longitudinal
axis of the pile. Coordinate pile driving to prevent damage to other
parts of the completed work.

Drive piles to within 2 inches of plan location at cutoff elevation for
cutoff locations above ground and within 6 inches of plan location for
cutoff locations below ground. The pile shall not be closer than 4
inches to any cap face. Drive piles so that the axial alignment is
within1/4 inch per foot, along the longitudinal axis, of the required
alignment. The CO may stop driving to check the pile alignment. Check
alignment of piles that cannot be internally inspected after
installation before the last 5 feet are driven. Do not pull laterally on
piles or splice to correct misalignment. Do not splice a properly
aligned section on a misaligned pile.

Place individual piles in pile groups either starting from the center of
the group and proceeding outward in both directions or starting at the
outside row and proceeding progressively across the group.

Correct all piles driven improperly, driven out of proper location,
misaligned, or driven below the designated cutoff elevation in an
approved manner. Replace piles damaged during handling or driving.
Obtain approval for the proposed method(s) of correcting or repairing
deficiencies.

**(a) Timber piles.** Do not use piles with checks wider than 1/2 inch.
Drive treated timber piles within 6 months after treatment. Handle and
care for pressure-treated piles according to AWPA Standard M 4.

**(b) Steel piles.** Furnish full-length, unspliced piles for lengths up
to 60 feet. If splices are required in the first pile driven and it is
anticipated that subsequent piles will also require splices, place the
splices in lower third of the pile. Splice lengths less than 10 feet are
not permitted and only 2 splices per pile are allowed.

Load, transport, unload, store, and handle steel piles so the metal is
kept clean and free from damage. Do not use piles that exceed the camber
and sweep permitted by allowable mill tolerance. Steel piles damaged
during installation are considered unsatisfactory unless the bearing
capacity is proven to be 100 percent of the required ultimate capacity
by load tests. Perform tests at no cost to the Government.

**(c) Precast and prestressed concrete piles.** Support concrete piles
during lifting or moving at the points shown on the plans or, if not so
shown, provide support at the quarter points. Provide slings or other
equipment when raising or transporting concrete piles to avoid bending
the pile or breaking edges.

Reject concrete piles with reduced strength caused by external defects
such as spalls, cracks, or internal defects such as cavities revealed
with non-destructive testing.

**(d) Concrete-filled pipe or steel shell piles.** Furnish and handle
the steel shells or pipes in accordance with (b) above. Cutting shoes
for shells or pipes may be inside or outside the shell. Use high-carbon
structural steel with a machined ledge for shell bearing or cast steel
with a ledge designed for attachment with a simple weld.

When practicable, drive all pile shells or pipes for a substructure unit
before placing concrete in any of the shells or pipes. Do not drive pile
shells or pipes within 15 feet of any concrete-filled pile shell or pipe
until the concrete has cured for at least 7 days or 3 days if using
high-early-strength concrete. Do not drive any pile shell or pipe after
it is filled with concrete.

Remove and replace shells that are determined to be unacceptable for use
due to breaks, bends, or kinks.

**551.09 Splices.** Submit details for pile field splices for approval.
Align and connect pile sections so the axis of the spliced pile is
straight.

**(a) Steel piles.** Submit a welder certification for each welder. Use
welders certified for structural welding.

Make surfaces to be welded smooth, uniform, and free from loose scale,
slag, grease, or other material that prevents proper welding. Steel may
be oxygen cut. Carbon-arc gouging, chipping, or grinding may be used for
joint preparation.

Weld according to AASHTO/AWS D 1.5 Bridge Welding Code. Weld the entire
pile cross-section using prequalified AWS groove weld butt joints. Weld
so there is no visual evidence of cracks, lack of fusion, undercutting,
excessive piping, porosity, or inadequate size. Manufactured splices may
be used in place of full penetration groove butt welds.

**(b) Concrete pile splices.** Use dowels or other acceptable mechanical
means to splice precast concrete or precast prestressed concrete piles.
Submit drawings of proposed splices for acceptance.

If dowels are used, cast the dowels into the tip end of the following
pile with corresponding holes at the butt end of the driven pile.
Serrate the holes to provide a mechanical bond. Separate the ends of the
piles by at least 1/2 inch. Clean all surfaces and dowel holes. Grout
the dowels in place and allow the grout to cure. Enclose the gap with
forms and inject a bonding agent capable of withstanding the impact and
driving forces and having the same compressive strength as the pile.
Follow the manufacturer's recommendations regarding the use and curing
of grouting and bonding products.

Attach manufactured splices to the concrete piles as recommended by the
manufacturer. The splice shall develop strengths in compression,
tension, and bending equal to or exceeding the strength of the pile
being spliced.

**(c) Concrete pile extensions.**

**(1) Precast concrete piles.** Extend precast concrete piles by
removing the concrete at the end of the pile and leaving 40 diameters of
reinforcement steel exposed. Remove the concrete to produce a face
perpendicular to the axis of the pile. Securely fasten reinforcement of
the same size as that used in the pile to the projecting reinforcing
steel. Form the extension to prevent leakage along the pile.

Immediately before placing concrete, wet the top of the pile thoroughly
and cover with a thin coating of neat cement, re-tempered mortar, or
other suitable bonding material. Place concrete of the same mix design
and quality as that used in the pile. Keep forms in place for not less
than 7 days after the concrete has been placed. Cure and finish
according to Section 552.

**(2) Prestressed piles.** Extend prestressed precast piles according to
(b) above. Include reinforcement bars in the pile head for splicing to
the extension bars. Do not drive extended prestressed precast piles.

**(d) Timber piles.** Do not splice timber piles.

**551.10 Heaved Piles.** Check for pile heave during the driving
operation. Take level readings immediately after each pile is driven and
again after piles within a radius of 15 feet are driven. Re-drive all
piles that heave more than 1/4 inches. Re-drive to the specified
resistance or penetration.

**551.11 Pile Load Tests.** Pile load tests are not required unless
specified to be performed in the contract.

**(a) Dynamic load test.** Use a qualified pile specialty consultant
with at least 3 years experience in dynamic load testing and analysis to
perform the dynamic load test, the case pile wave analysis program
(CAPWAP), and the wave equation analysis including the initial wave
equation analysis specified in Subsection 551.03(b). Submit a resume of
the specialty consultant for approval.

Furnish equipment and perform dynamic load tests according to ASTM D
4945 under the supervision of the CO.

Place the piles designated as dynamic load test piles in a horizontal
position and not in contact with other piles. Drill holes for mounting
instruments near the head of the pile. Mount the instruments, and take
wave speed measurements. Place the designated pile in the leads. Provide
at least a 4-foot by 4-foot rigid platform with a 3½-foot safety rail
that can be raised to the top of the pile.

Drive the pile to the depth at which the dynamic test equipment
indicates that the required ultimate pile capacity is achieved. If
necessary to maintain stresses in the pile below the values in
Subsection 551.03(b)(2), reduce the driving energy transmitted to the
pile by using additional cushions or reducing the energy output of the
hammer. If nonaxial driving is indicated, immediately realign the
driving system.

At least 24 hours after the initial driving, re-drive each dynamic load
test pile with instrumentation attached. Warm the hammer before
re-driving by applying at least 20 blows to another pile. Re-drive the
dynamic load test pile for a maximum penetration of 6 inches, a maximum
of 50 blows, or to practical driving refusal, whichever occurs first.
Practical driving refusal is defined as 15 blows per inch for steel
piles, 8 blows per inch for concrete piles, and 5 blows per inch for
timber piles.

Verify the assumptions used in the initial wave equation analysis
submitted according to Subsection 551.03(b) using CAPWAP. Analyze one
blow from the original driving and one blow from the re-driving for each
pile tested.

Perform additional wave equation analyses with adjustments based on the
CAPWAP results. Provide a graph showing blow count versus ultimate
capacity. For open-ended diesel hammers, provide a blow count versus
stroke graph for the ultimate capacity. Provide the driving stresses,
transferred energy, and pile capacity as a function of depth for each
dynamic load test.

Based on the results of the dynamic load testing, CAPWAP analyses, and
wave equation analyses, the order list and production driving criteria
may be approved and the required cut-off elevations provided, or
additional test piles and load testing may be specified. This
information will be provided within 7 days after receipt of the order
list and all required test data for the test piles driven.

**(b) Static load tests.** Perform static load tests according to ASTM D
1143 using the quick load test method except as modified herein. Submit
drawings of the proposed loading apparatus for acceptance according to
the following:

**(1)** Have a professional engineer prepare the drawings.

**(2)** Furnish a loading system capable of applying 150 percent of the
ultimate pile capacity or 1,000 tons, whichever is less.

**(3)** Construct the apparatus to allow increments of load to be placed
gradually without causing vibration to the test pile.

When tension (anchor) piles are required, drive tension piles at the
location of permanent piles when feasible. Do not use timber or tapered
piles installed in permanent locations as tension piles. Take the test
to plunging failure or the capacity of the loading system, whichever
occurs first.

The allowable axial pile load is defined as 50 percent of the failure
load. The failure load is defined as follows:

• For piles 24 inches or less in diameter or diagonal width, the load
that produces a settlement at failure of the pile head equal to:

$$Sf\  = \ S\  + \ (0\text{.}\text{15}\  + \ 0\text{.}\text{008}D)\ $$

• For piles greater than 24 inches in diameter or diagonal width:

$$Sf\  = \ S\  + \ \frac{D}{\text{30}}$$

where:

*S~f\ ~*= Settlement at failure in inches

*D* = Pile diameter or diagonal width in inches

*S* = Elastic deformation of pile in inches

Determine top elevation of the test pile immediately after driving and
again just before load testing to check for heave. Wait a minimum of 3
days between the driving of any anchor or load test piles and the
commencement of the load test. Before testing, re-drive or jack to the
original elevation any pile that heaves more than 1/4 inch.

After completion of the load testing, remove or cut off any test or
anchor piling not a part of the finished structure at least 2 feet below
either the bottom of footing or the finished ground elevation.

Based on the results of the static load testing, the order list and
production driving criteria may be approved and the required cut-off
elevations provided or additional load tests may be specified. This
information will be provided within 7 days after receipt of the order
list and all required test data for the test piles driven.

**551.12 Pile Cutoffs.** Cut off the tops of all permanent piles and
pile casings at the required elevation. Cut off the piles clean and
straight parallel to the bottom face of the structural member in which
they are embedded. Dispose of cutoff lengths according to Subsection
203.05(a).

**(a) Steel piles.** Do not paint steel to be embedded in concrete.
Before painting the exposed steel pile, thoroughly clean the metal
surface of any substance that may inhibit paint adhesion. Use aluminum
colored paint system 2 according to Section 563. Paint piles before
driving. Use one prime coat and 2 finish coats on trestles or other
exposed piling to at least 4 feet below the finished groundline or
waterline. Paint exposed piling above finished groundline or waterline
with one field finish coat.

**(b) Wood piles.** Treat the heads of all treated timber piles which
are not embedded in concrete by one of the following methods.

**(1)** Reduce the moisture content of the wood to no more than 25
percent with no free moisture on the surface. Brush apply one
application of creosote-coal tar solution as required in AWPA Standards.

Build up a protective cap by applying alternate layers of loosely woven
fabric and hot asphalt or tar, similar to membrane waterproofing, using
3 layers of asphalt or tar and 2 layers of fabric. Use fabric at least 6
inches wider in each direction than the diameter of the pile. Turn the
fabric down over the pile and secure the edges by binding with 2 turns
of No. 10 galvanized wire. Apply a final layer of asphalt or tar to
cover the wire. Neatly trim the fabric below the wires.

**(2)** Cover the sawed surface with 3 applications of a hot mixture of
60 percent creosote and 40 percent roofing pitch, or thoroughly brush
coat with 3 applications of hot creosote and cover with hot roofing
pitch. Place a covering of galvanized sheet metal over the coating and
bend down over the sides of each pile.

**551.13 Unsatisfactory Piles.** Correct unsatisfactory piles by an
approved method. Methods of correcting unsatisfactory piles may include
one or more of the following:

**(a)** Use of the pile at a reduced capacity;

**(b)** Install additional piles;

**(c)** Repair damaged piles; and

**(d)** Replace damaged piles.

**551.14 Placing Concrete in Steel Shell or Pipe Piles.** After driving,
clean the inside of shells and pipes by removing all loose material.
Keep the shell or pipe substantially water tight. Provide suitable
equipment for inspecting the entire inside surface of the driven shell
or pipe just before placing concrete.

**(a) Reinforcing steel.** When reinforcing steel is required, make the
spacing between adjacent cage elements at least 5 times the maximum size
of aggregate in the concrete.

Securely tie concrete spacers or other approved spacers at fifth points
around the perimeter of the reinforcing steel cage. Install spacers at
intervals not to exceed 10 feet measured along the length of the cage.

Place the reinforcement cage into the driven shell or pipe when the
concrete reaches the planned bottom elevation of the reinforcement.
Support the reinforcement so it remains within 2 inches of the required
vertical location. Support the cage from the top until the concrete
reaches the top of the pile.

**(b) Concrete.** Construct concrete according to Section 552. Place
concrete in one continuous operation from the bottom to the top of the
pile. Before the initial concrete set, consolidate the top 10 feet of
the concrete pile using approved vibratory equipment.

**551.15 Acceptance.** Pile material will be evaluated under Subsections
106.02 and 106.03.

Furnish production certifications with each shipment of the following:

**(a)** Concrete piles;

**(b)** Sheet piles, steel H-piles, steel shells, and steel pipes; and

**(c)** Treated timber piles. Stamp each pile with an identification
mark and date of inspection.

Driving piles and related work will be evaluated under Subsections
106.02 and 106.04.

Concrete for steel shells or pipe piles will be evaluated under Section
552.

Reinforcing steel for steel shells or pipe piles will be evaluated under
Section 554.

Measurement

**551.16** Measure the Section 551 items listed in the bid schedule
according to Subsection 109.02 and the following as applicable.

When measurement is by the linear foot, measure the length of pile from
the cutoff elevation to the tip.

Measure splices required to drive piles deeper than the estimated tip
elevation.

Payment

**551.17** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 551 pay items listed in the bid
schedule except the concrete-filled pipe or steel shell pile unit bid
price will be adjusted according to Subsection 106.05. Payment will be
full compensation for the work prescribed in this Section. See
Subsection 109.05.

Payment for concrete-filled pipe or steel shell piles will be made at a
price determined by multiplying the unit bid price by an adjusted pay
factor (*PFa*) determined as follows:

*PFa* = 1 ‑ 0.5 (1‑*PF*)

where:

*PF* = Pay factor for concrete as determined under Section 552.

## Section 552. --- STRUCTURAL CONCRETE

Description

**552.01** This work consists of furnishing, placing, finishing, and
curing concrete in bridges, culverts, and other structures.

Structural concrete class is designated as shown in Table 552-1.

Material

**552.02** Conform to the following Subsections:

Air-entraining admixture 711.02

Chemical admixtures 711.03

Coarse aggregate 703.02

Color coating 725.24

Curing material 711.01

Elastomeric bearing pads 717.10

Elastomeric compression joint seals 717.16

Fine aggregate 703.01

Fly ash 725.04

Ground iron blast-furnace slag 725.04

Hydraulic cement 701.01

Joint fillers and sealants 712.01

Latex modifier 711.04

Linseed oil 725.14

Masonry cement 701.02

Silica fume (microsilica) 725.04

Water 725.01

Construction Requirements

**552.03 Composition (Concrete Mix Design).** Design and produce
concrete mixtures that conform to Tables 552-1 and 552-2 for the class
of concrete specified. Determine design strength values according to ACI
318. Structural concrete shall also conform to the following ACI
specifications.

• ACI 211.1 Standard Practice for Selecting Proportions for Normal,
Heavy Weight and Mass Concrete;

• ACI 211.2 Standard Practice for Selecting Proportions for Structural
Light Weight Concrete; and

• ACI 211.3 Guide for Selecting Proportions of No-Slump Concrete.

Table 552-1

Composition of Concrete

+--------------+----------------+-----------+----------+-------------+
| **Class**    | **Minimum      | **        | **Slum   | **Nominal   |
|              | Cement**       | Maximum** | p^(1)^** | Maximum     |
| **of**       |                |           |          | Aggregate   |
|              | **Content**    | **W/C     | **(i     | Size        |
| **Concrete** |                | Ratio**   | nches)** | (inches)**  |
|              | **(pounds      |           |          |             |
|              | per**          |           |          |             |
|              |                |           |          |             |
|              | **cubic        |           |          |             |
|              | yard)**        |           |          |             |
+--------------+----------------+-----------+----------+-------------+
| A            | 611            | 0.49      | 2 to 4   | 1½          |
+--------------+----------------+-----------+----------+-------------+
| A(AE)        | 611            | 0.44      | 1 to 4   | 1½          |
+--------------+----------------+-----------+----------+-------------+
| B            | 517            | 0.58      | 2 to 4   | 2½          |
+--------------+----------------+-----------+----------+-------------+
| B(AE)        | 517            | 0.58      | 2 to 4   | 2½          |
+--------------+----------------+-----------+----------+-------------+
| C            | 658            | 0.49      | 2 to 4   | 3/4         |
+--------------+----------------+-----------+----------+-------------+
| C(AE)        | 658            | 0.44      | 1 to 3   | 3/4         |
+--------------+----------------+-----------+----------+-------------+
| D(AE)^(2)^   | 611            | 0.40      | 1 to 3   | 1½          |
+--------------+----------------+-----------+----------+-------------+
| E(AE)^(3)^   | 611            | 0.40      | 4 to     | 3/4         |
|              |                |           | 6^(4)^   |             |
+--------------+----------------+-----------+----------+-------------+
| P            | 658            | 0.44      | 0 to 4   | 1           |
| (            |                |           |          |             |
| Prestressed) |                |           |          |             |
+--------------+----------------+-----------+----------+-------------+
| Seal         | 658            | 0.54      | 4 to 8   | 1½          |
+--------------+----------------+-----------+----------+-------------+

\(1\) Maximum slump is 8 inches if approved mix design includes a
high-range water reducer.

\(2\) Concrete with a water reducing and retarding admixture conforming
to AASHTO M 194, type D.

\(3\) A latex modified concrete with 0.037 gallons of modifier per pound
of cement.

\(4\) Measure the slump 4 to 5 minutes after the concrete is discharged
from the mixer.

Table 552-2

Minimum Air Content for Air Entrained Concrete

+----------------------------------+-----------------------------------+
| **Nominal Maximum**              | **As Delivered Minimum**          |
|                                  |                                   |
| **Aggregate Size**               | **Air Content ^(1)^ (%)**         |
+----------------------------------+-----------------------------------+
| 3 inch                           | 3.0                               |
+----------------------------------+-----------------------------------+
| 2½ inch                          | 3.5                               |
+----------------------------------+-----------------------------------+
| 2 inch                           | 3.5                               |
+----------------------------------+-----------------------------------+
| 1½ inch                          | 4.0                               |
+----------------------------------+-----------------------------------+
| 1 inch                           | 4.5                               |
+----------------------------------+-----------------------------------+
| 3/4 inch                         | 4.5                               |
+----------------------------------+-----------------------------------+
| 1/2 inch                         | 5.5                               |
+----------------------------------+-----------------------------------+

> \(1\) These air contents apply to the total mix. When testing these
> concretes, aggregate larger than 1½ inches is removed by handpicking
> or sieving, and air content is determined on the minus 1½-inch
> fraction of the mix. Air content of the total mix is computed from the
> value determined on the minus 1½-inch fraction.

Submit concrete mix designs on FHWA Form 1608.

Verify mixture design with trial mixes prepared according to ACI 318
from proposed source(s) or with previous concrete production data for
the mixture design submitted from proposed source(s). Submit written
concrete mix designs for approval at least 36 days before production.
Each mix design submittal shall include all of the following:

**(a)** Project identification;

**(b)** Name and address of Contractor and concrete producer;

**(c)** Mix design designation;

**(d)** Class of concrete and intended use;

**(e)** Material proportions;

**(f)** Name and location of material sources for aggregate, cement,
admixtures, and water; and

**(g)** Type of cement and type of cement replacement if used. Fly ash,
ground iron blast-furnace slag, or silica fume may partially replace
cement in any mix as follows:

**(1) Fly ash.**

*(a) Class F.* Not more than 20 percent of the minimum mass of portland
cement in Table 552-1 may be replaced with class F fly ash at the rate
of 1.5 parts fly ash per 1 part portland cement.

*(b) Class C.* Not more than 25 percent of the minimum mass of portland
cement in Table 552-1 may be replaced with class C fly ash at the rate
of 1 part fly ash per 1 part portland cement.

**(2) Ground iron blast-furnace slag.** Not more than 50 percent of the
minimum mass of portland cement in Table 552-1 may be replaced with
ground iron blast-furnace slag at the rate of 1 part slag per 1 part
portland cement.

**(3) Silica fume (microsilica).** Not more than 10 percent of the
minimum mass of portland cement in Table 552-1 may be replaced with
silica fume at the rate of 1 part silica fume per 1 part portland
cement.

For concrete exposed to deicing chemicals, fly ash will constitute no
more than 25 percent and silica fume no more than 10 percent of the
total replacement weight. Additionally, fly ash, slag, and silica fume
will constitute no more than 50 percent of the total replacement weight.

The water/cement ratio for modified concrete is the ratio of the mass of
water to the combined masses of hydraulic cement and cement substitute.

**(h)** Cement content in pounds per cubic yard of concrete.

**(i)** The saturated surface dry batch mass of the coarse and fine
aggregate in pounds per cubic yard of concrete.

**(j)** Water content in pounds per cubic yard of concrete.

**(k)** Water/cement ratio.

**(l)** Dosage of admixtures. When requested by the CO, provide a
qualified person from the admixture manufacturer to help establish the
proper dosage. Do not mix chemical admixtures together in a mix unless
they are compatible. Furnish supporting documentation of compatibility
from the manufacturers. Do not use high range water reducers for bridge
decks.

**(1) Air-entraining admixtures.** Entrained air may be obtained with
either an air entraining hydraulic cement or an air entraining
admixture.

**(2) Set accelerating admixtures.** Do not use chloride accelerators.
Do not use set accelerating admixtures with class P (prestressed)
concrete.

**(3) Hydration stabilizing admixtures.** Hydration stabilizing
admixtures may be used to extend the allowable delivery time for
concrete. Base the dosage on the time needed to delay the initial set of
the concrete for delivery and discharge on the job. Include the design
discharge time limit in the dosage submittal. The maximum allowable
design discharge time is 3.50 hours.

**(m)** Sieve analysis of fine and coarse aggregate.

**(n)** Absorption of fine and coarse aggregate.

**(o)** Bulk specific gravity (dry and saturated surface dry) of fine
and coarse aggregate.

**(p)** Dry rodded unit mass of coarse aggregate in pounds per cubic
foot.

**(q)** Fineness modulus (FM) of fine aggregate.

**(r)** Material certifications for cement, admixtures, and aggregate.

**(s)** Target values for concrete slump with and without high-range
water reducers.

**(t)** Target values for concrete air content. Include the proposed
range of air content for concrete to be incorporated into the work.
Describe the methods by which air content will be monitored and
controlled. Provide acceptable documentation that the slump and
compressive strength of the concrete are within specified limits
throughout the full range of proposed air content.

**(u)** Concrete unit mass.

**(v)** Specified design strength (f^'^~c~) and required average
strength (f^'^~cr~) for the concrete mixture at 28 days based on ACI
318. When insufficient data is available, select (f^'^~cr~) from Table
552-3. Pending 28-day strength results, a mix design may be approved on
the basis that 7-day compressive strength results meet or exceed 85
percent of the required average strength (f^'^~cr~) at 28 days.

Table 552-3

Required Average Strength

+----------------------------------+-----------------------------------+
| **Specified Design Strength      | **Required Average Strength       |
| (f^'^~c~)**                      | (f^'^~cr~)**                      |
|                                  |                                   |
| **(pounds per square inch)**     | **(pounds per square inch)**      |
+----------------------------------+-----------------------------------+
| Less than 3000                   | f^'^~c~ + 1000                    |
+----------------------------------+-----------------------------------+
| 3000 to 5000                     | f^'^~c~ + 1200                    |
+----------------------------------+-----------------------------------+
| Greater than 5000                | f^'^~c~ + 1500                    |
+----------------------------------+-----------------------------------+

**(w)** Compressive strengths test results at 7 and 28 days. Each
compressive strength test consists of two or more cylinders tested
according to AASHTO T 22 at the same age.

**(x)** Material samples if requested.

Begin production only after the mix design is approved.

Furnish a new mix design for approval if there is a change in a source
of material or when the fineness modulus of the fine aggregate changes
by more than 0.20.

**552.04 Storage and Handling of Material.** Store and handle all
material in a manner that prevents segregation, contamination, or other
harmful effects. Do not use cement and fly ash containing evidence of
moisture contamination. Store and handle aggregate in a manner that
ensures a uniform moisture content at the time of batching.

**552.05 Measuring Material.** Batch the concrete according to the
approved mix design and the following tolerances:

  -------------------------------- --------------------------------------
  Cement                           ±1 percent

  Water                            ±1 percent

  Aggregate                        ±2 percent

  Additive                         ±3 percent
  -------------------------------- --------------------------------------

A calibrated volumetric system may be used if the specified tolerances
are maintained.

**552.06 Batching Plant, Mixers, and Agitators.** Use a batching plant,
mixer, and agitator conforming to AASHTO M 157. Continuous volumetric
mixing equipment shall conform to AASHTO M 241.

**552.07 Mixing.** Mix the concrete in a central-mix plant or in truck
mixers. Operate all equipment within manufacturer\'s recommended
capacity. Produce concrete of uniform consistency.

**(a) Central-mix plant.** Dispense liquid admixtures through a
controlled flowmeter. Use dispensers with sufficient capacity to
measure, at one time, the full quantity of admixture required for each
batch. If more than one admixture is used, dispense each with separate
equipment.

Charge the coarse aggregate, one third of the water, and all air
entraining admixture into the mixer first, then add remainder of the
material.

Mix for at least 50 seconds. Begin mixing time after all cement and
aggregate are in the drum. Add the remaining water during the first
quarter of the mixing time. Add 4 seconds to the mixing time if timing
starts the instant the skip reaches its maximum raised position.
Transfer time in multiple-drum mixers is included in mixing time. Mixing
time ends when the discharge chute opens.

Remove the contents of an individual mixer before a succeeding batch is
charged into the drum.

**(b) Truck mixer.** Do not use mixers with any section of the blades
worn 1 inch or more below the original manufactured height. Do not use
mixers and agitators with accumulated hard concrete or mortar in the
mixing drum.

Add admixtures to the mix water before or during mixing.

Charge the batch into the drum so a portion of the mixing water enters
in advance of the cement.

Mix each batch of concrete according to AASHTO M 157.

**552.08 Delivery.** Produce and deliver concrete to permit a continuous
placement with no concrete achieving initial set before the remaining
concrete being placed adjacent to it. Deliver, handle, and place
concrete in such a manner as to minimize rehandling of the concrete and
prevent any damage to the structure.

Do not place concrete that has developed an initial set. Never re-temper
concrete by adding water.

If a hydration stabilizing admixture is approved for use in the concrete
mix, deliver and place the concrete within the approved design discharge
time limit. Limit the slump loss to no more than 2 inches during the
stabilization period. An approved and compatible hydration activator may
be used at the discharge sit to ensure proper placement and testing.

**(a) Truck mixer/agitator.** Use the agitating speed for all rotation
after mixing. When a truck mixer or truck agitator is used to transport
concrete that is completely mixed in a stationary central construction
mixer, mix during transportation at manufacturer\'s recommended
agitating speed.

If the concrete has not obtained an initial set, water and admixtures in
the approved mix design may be added one time at the project to obtain
the required slump or air content. The total of all water in the mix
shall not exceed the maximum water/cement ratio of the approved mix
design. Remix the concrete and added water or admixtures with 30
revolutions at mixing speed. After the initial introduction of mixing
water to cement or cement to aggregates, complete the remixing within
the time specified in Table 552-4. After the beginning of the addition
of the cement, complete the discharge of the concrete within the time
specified in Table 552-4.

Table 552-4

Concrete Remixing and Discharge Time Limits

+------------------------+----------------+-----------+---------------+
| **Cement Type**        | **Admixtures** | *         | **Discharge** |
|                        |                | *Remixing |               |
|                        |                | Time      | **Time Limit  |
|                        |                | Limit     | (hour)**      |
|                        |                | (hour)**  |               |
+------------------------+----------------+-----------+---------------+
| Type I, IA, II, IIA,   | None           | 0.75      | 1.00          |
| V, or approved blended |                |           |               |
| hydraulic cement       |                |           |               |
+------------------------+----------------+-----------+---------------+
| Type I, IA, II, IIA,   | AASHTO M 194,  | 1.25      | 1.50          |
| V, or approved blended | type B, D, or  |           |               |
| hydraulic cement       | G              |           |               |
+------------------------+----------------+-----------+---------------+
| Type I, IA, II, IIA,   | Hydration      | 3.00      | Approved      |
| V, or approved blended | stabilizer     |           | design        |
| hydraulic cement       |                |           | discharge     |
|                        |                |           | time limit,   |
|                        |                |           | 3.50 maximum  |
+------------------------+----------------+-----------+---------------+
| Type III ^(1)^         | None           | 0.50      | 0.75          |
+------------------------+----------------+-----------+---------------+
| Type III ^(1)^         | AASHTO M 194,  | 1.00      | 1.25          |
|                        | type B, D, or  |           |               |
|                        | G              |           |               |
+------------------------+----------------+-----------+---------------+

\(1\) AASHTO M 85, type III.

**(b) Nonagitating equipment.** Nonagitating equipment may be used to
deliver concrete if the concrete discharge is completed within 20
minutes from the beginning of the addition of the cement to the mixing
drum. Use equipment with smooth, mortar tight, metal containers capable
of discharging the concrete at a controlled rate without segregation.
Provide covers when needed for protection.

**552.09 Quality Control of Mix.** Submit and follow a quality control
plan according to Sections 153 and 154 as applicable and the following.

**(a) Mixing.** Designate a competent and experienced concrete
technician to be at the mixing plant in charge of the mixing operations
and to be responsible for the overall quality control including:

**(1)** The proper storage and handling of all components of the mix;

**(2)** The proper maintenance and cleanliness of plant, trucks, and
other equipment;

**(3)** The gradation testing of fine and coarse aggregates;

**(4)** The determination of the fineness modulus of fine aggregate;

**(5)** The measurement of moisture content of the aggregates and
adjusting the mix proportions as required before each day\'s production
or more often if necessary to maintain the required water/cement ratio;

**(6)** The computation of the batch masses for each day\'s production
and the checking of the plant\'s calibration as necessary; and

**(7)** The completion of batch tickets. Include the following
information:

*(a)* Concrete supplier;

*(b)* Ticket serial number;

*(c)* Date and truck number;

*(d)* Contractor;

*(e)* Structure or location of placement;

*(f)* Mix-design and concrete class;

*(g)* Component quantities and concrete total volume;

*(h)* Moisture corrections for aggregate moisture;

*(i)* Total water in mix at plant;

*(j)* Time of batching and time at which discharge must be completed;

*(k)* Maximum water that may be added to the mix at the project; and

*(l)* If a hydration stabilizing admixture is used, record the slump at
the plant after adding the stabilizer.

Provide equipment necessary for the above tests and controls. Furnish
copies of work sheets for (3), (4), (5), and (6) as they are completed.

**(b) Delivery and sampling.** Designate at least one competent and
experienced concrete technician to be at the project and be responsible
for concrete delivery, discharge operations, and sampling that include
the following:

**(1)** The verification that adjustments to the mix before discharge
comply with the specifications.

**(2)** The completion of the batch ticket, the recording of the
apparent water/cement ratio, and the time discharge is completed.
Furnish a copy of each batch ticket at the time of placement.

**(3)** The furnishing of all equipment and the performing of
temperature, unit mass, air content, slump, and other tests to verify
specification compliance before and during each placement operation.

If hydration stabilizing admixture is used, determine the slump before
placement. Do not use concrete with a slump loss of more than 2 inches
as compared to the slump recorded at the batch plant.

Sample every batch after at least 0.25 cubic yards are discharged and
before placing any of the batch in the forms. When continuous mixing is
used, sample approximately every 10 cubic yards. Test the air content
according to AASHTO T 152 or T 196.

Test unit mass, slump, and temperature according to Subsection 552.19.

If 3 successive samples are tested and compliance to the specifications
is indicated, screening tests may be reduced to an approved frequency.
Resume initial testing frequency if a test shows a failing temperature,
air content, slump or when directed.

If there is no prior experience with the approved mix design or if
special handling procedures, such as pumping, change one or more of the
characteristics between discharge of the load and placing in the forms,
correlate the discharge tests with the placement tests to define these
changes. Provide documentation. Repeat the correlations as often as
necessary or as directed.

**(4)** Take samples according to AASHTO T 141 from specified loads.
Composite samples are not required. The point of sampling is from the
discharge stream at the point of placement. Provide cylinder molds. Make
at least 4 compressive strength test cylinders, provide the appropriate
initial curing, and carefully transport the cylinders to the project
curing facility. Two of the 4 cylinders will be used for 28-day
compressive strength tests. The remaining cylinders will be used for
verification, projected strengths, or other purposes specified. Assist
in the performing of other tests as requested.

**552.10 Temperature and Weather Conditions.** Maintain the temperature
of the concrete mixture just before placement between 50 and 90 ºF,
except maintain the concrete for bridge decks between 50 and 80 ºF.

**(a) Cold weather.** Cold weather is defined as a period when, for more
than 3 consecutive days, the following conditions exist: (1) the average
of the highest and the lowest temperatures occurring during the period
from midnight to midnight is less than 40 F and (2) the air temperature
is not greater than 50 F for more than one-half of any 24-hour period.

When cold weather is reasonably expected or has occurred within 7 days
of anticipated concrete placement, submit a detailed plan for the
producing, transporting, placing, protecting, curing, and temperature
monitoring of concrete during cold weather. ACI 306 may be used for
guidance in developing the plan. Include procedures for accommodating
abrupt changes in weather conditions. Do not commence placement until
plan is accepted. Acceptance of a plan will take at least 1 day.

Have all material and equipment required for protection available at or
near the project before commencing cold weather concreting.

Remove all snow, ice, and frost from the surfaces, including
reinforcement and subgrade, against which the concrete is to be placed.
The temperature of any surface that comes into contact with fresh
concrete shall be at least 35 ºF and shall be maintained at a
temperature of 35 ºF or above during the placement of the concrete.

Place heaters and direct ducts so as not to cause concrete drying or
fire hazards. Vent exhaust flue gases from combustion heating units to
the outside of any enclosures. Heat the concrete components in a manner
that is not detrimental to the mix. Do not heat cement or permit the
cement to come into contact with aggregates that are hotter than 100 ºF.
Concrete at the time of placement shall be of uniform temperature and
free of frost lumps. Do not heat aggregates with a direct flame or on
sheet metal over fire. Do not heat fine aggregate by direct steam. The
addition of salts to prevent freezing is not permitted.

During cold weather, protect all concrete for at least 72 hours
according to Table 552‑5. Protect concrete exposed in the final
construction for at least 7 days according to Table 552-5.

Furnish and place continuously recording surface temperature measuring
devices that are accurate within ±2 ºF.

At the end of the protection period, allow the concrete to cool
gradually over 24 hours at a rate not to exceed the maximum values shown
in Table 552-5. All protection may be removed when the concrete surface
temperature is within 25 ºF of the ambient air temperature.

Table 552-5

Cold Weather Concrete Surface Temperatures

+-----------------------------+-------+----------+----------+---------+
| Minimum section size        | \< 12 | 12 - 36  | 36 - 72  | \> 72   |
|                             |       |          |          |         |
| dimension, inches           |       |          |          |         |
+-----------------------------+-------+----------+----------+---------+
| Minimum temperature of      | 55 ºF | 50 ºF    | 45 ºF    | 40 ºF   |
|                             |       |          |          |         |
| concrete during protection  |       |          |          |         |
| period                      |       |          |          |         |
+-----------------------------+-------+----------+----------+---------+
| Maximum allowable           | 50 ºF | 40 ºF    | 30 ºF    | 20 ºF   |
| temperature drop in any     |       |          |          |         |
| 24-hour period after end of |       |          |          |         |
| protection                  |       |          |          |         |
+-----------------------------+-------+----------+----------+---------+

**(b) Hot weather.** Hot weather is any time during the concrete
placement that the ambient temperature at the work site is above 90 ºF.

In hot weather, cool all surfaces that come in contact with the mix to
below 90 ºF. Cool by covering with wet burlap or cotton mats, fog
spraying with water, covering with protective housing, or by other
approved methods.

During placement, maintain concrete temperature by using any combination
of the following:

**(1)** Shade the material storage areas or production equipment;

**(2)** Cool aggregate by sprinkling; and

**(3)** Cool aggregate and water by refrigeration or replacing a portion
or all of the mix water with flaked or crushed ice to the extent that
the ice completely melts during mixing of the concrete.

**(c) Evaporation.** When placing concrete in bridge decks or other
exposed slabs, limit expected evaporation rate to less than 0.1 pound
per square foot per hour as determined by Figure 552-1.

When necessary, take one or more of the following actions:

**(1)** Construct windbreaks or enclosures to effectively reduce the
wind velocity throughout the area of placement.

**(2)** Use fog sprayers upwind of the placement operation to
effectively increase the relative humidity.

**(3)** Reduce the temperature of the concrete according to (b) above.

**(d) Rain.** At all times during and immediately after placement,
protect the concrete from rain.

**552.11 Handling and Placing Concrete.** Perform the work under Section
208. Construct reinforcing steel, structural steel, bearing devices,
joint material, and miscellaneous items according to the appropriate
Sections.

**(a) General.** Design and construct falsework and forms according to
Section 562. Handle, place, and consolidate concrete by methods that do
not cause segregation and will result in dense homogeneous concrete that
is free of voids and rock pockets. Placement methods shall not cause
displacement of reinforcing steel or other material that is embedded in
the concrete. Place and consolidate concrete before initial set. Do not
retemper concrete by adding water to the mix.

Do not place concrete until the forms, all embedded material, and the
adequacy of the foundation material have been inspected.

Remove all mortar, debris, and foreign material from the forms and
reinforcing steel before commencing placement. Thoroughly moisten the
forms and subgrade immediately before concrete is placed against them.
Temporary form spreader devices may be left in place until concrete
placement precludes their need, after which they shall be removed.

Place concrete continuously without interruption between planned
construction or expansion joints. The delivery rate, placing sequence,
and methods shall be such that fresh concrete is always placed and
consolidated against previously placed concrete before initial set has
occurred in the previously placed concrete. Do not allow the time
between the placement of successive batches to exceed 30 minutes.

During and after placement of concrete, do not damage previously placed
concrete or break the bond between the concrete and reinforcing steel.
Keep workers off fresh concrete. Do not support platforms for workers
and equipment directly on reinforcing steel. Once the concrete is set,
do not disturb the forms or reinforcing bars that project from the
concrete until it is of sufficient strength to resist damage.

![](media/image1.png){width="4.3125in" height="5.236111111111111in"}

Figure 552-1

Evaporation Rate of Surface Moisture

> **Note:** Example shown by dashed lines is for an air temperature of
> 65 ºF, relative humidity of 45 percent, concrete temperature of 65 ºF,
> and a wind velocity of 15 miles per hour. This results in a rate of
> evaporation of 0.13 pounds per square foot per hour.

**(b) Sequence of placement.**

**(1) Substructures.** Do not place loads on finished bents, piers, or
abutments until concrete cylinder tests from the same concrete cured
under the same conditions as the substructure element indicate that all
concrete has at least 80 percent of its required 28-day compressive
strength.

**(2) Vertical members.** For vertical members less than 15 feet in
height, allow the concrete to set for at least 30 minutes before placing
integral horizontal members. For vertical members over 15 feet in
height, allow at least 12 hours. Do not transfer loads from horizontal
members until the concrete has reached the specified strength and has
been in place at least 7 days.

Do not mount friction collars or falsework brackets on vertical members
until the concrete has cured for at least 7 days or has reached
specified strength.

**(3) Superstructures.** Place concrete in the superstructure only after
the substructure forms are stripped to allow inspection of the
supporting concrete.

For concrete placed in T-beams or deck girders with depths greater than
4 feet, allow 5 days cure time for the stem concrete before placement of
the top or deck slab.

For box girders, place the bottom slab and stems in one or separate
placements. Do not place the top slab until the stems have 5 days cure
time.

**(4) Arches.** To minimize shrinkage stresses, place concrete for
arches in alternate lateral sections. Placement sequence should take
into account deflections of the arch centering, with the abutment
sections preferably placed last. Place other sections symmetrically with
respect to the center of the bridge span. Where wide barrel arches
require a longitudinal joint, place concrete on each side of such joint
independently of the centering to avoid relative settlements. Bond the
sections together with suitable keys or dowels.

**(5) Box culverts.** Place the base slab of box culverts and allow to
set 24 hours before the remainder of the culvert is constructed.

**(6) Precast elements.** Place and consolidate concrete so that
shrinkage cracks are not produced in the member.

**(c) Placing methods.** Use equipment of sufficient capacity that is
designed and operated to prevent mix segregation and mortar loss. Do not
use equipment that causes vibrations that could damage the
freshly-placed concrete. Do not use equipment with aluminum parts that
come in contact with the concrete. Remove set or dried mortar from
inside surfaces of placing equipment.

Place concrete as near as possible to its final position. Do not place
concrete in horizontal layers greater than 1.5 feet thick. Do not exceed
the vibrator capacity to consolidate and merge the new layer with the
previous layer. Do not place concrete at a rate that, when corrected for
temperature, exceeds the design loading of the forms.

Do not drop unconfined concrete more than 5 feet. Concrete may be
confined by using a tube fitted with a hopper head or other approved
device that prevents mix segregation and mortar spattering. This does
not apply to cast-in-place piling when concrete placement is completed
before initial set occurs in the concrete placed first.

Operate concrete pumps so that a continuous stream of concrete without
air pockets is delivered at the tube discharge. Do not use conveyor belt
systems longer than 550 feet when measured from end to end of the total
belt assembly. Arrange the belt assembly so that each section discharges
into a vertical hopper to the next section without mortar adhering to
the belt. Use a hopper, chute, and deflectors at the discharge end of
the conveyor belt system to cause the concrete to drop vertically.

**(d) Consolidation.** Provide sufficient hand-held internal concrete
vibrators suitable for the conditions of concrete placement. Use
vibrators conforming to Table 552-6. Provide rubber-coated vibrators
when epoxy-coated reinforcement is used.

Provide a sufficient number of vibrators to consolidate each batch as it
is placed. Provide a spare vibrator at the site in case of breakdown.
Use external form vibrators only when the forms have been designed for
external vibration and when internal vibration is not possible.

Table 552-6

Hand Held Vibratory Requirements

+------------------------+-----------------------+---------------------+
| **Head Diameter**      | **Frequency**         | **Radius of         |
|                        |                       | Action**            |
| **(inches)**           | **                    |                     |
|                        | (vibrations/minute)** | **(inches)**        |
+------------------------+-----------------------+---------------------+
| 3/4 to 1½              | 10,000 to 15,000      | 3 to 5              |
+------------------------+-----------------------+---------------------+
| 1¼ to 2½               | 9,000 to 13,500       | 5 to 10             |
+------------------------+-----------------------+---------------------+
| 2 to 3½                | 8,000 to 12,000       | 7 to 9              |
+------------------------+-----------------------+---------------------+

Consolidate all concrete by mechanical vibration immediately after
placement. Manipulate vibrators to thoroughly work the concrete around
reinforcement, embedded fixtures, corners, and angles in the forms. Do
not cause segregation. Do not consolidate concrete placed underwater.
Supplement vibration with spading, as necessary, to ensure smooth
surfaces and dense concrete along form surfaces, in corners, and at
locations impossible to reach with the vibrators.

Vibrate the concrete at the point of deposit and at uniformly spaced
points not farther apart than 1.5 times the radius over which the
vibration is visibly effective. Insert vibrators so that the affected
vibrated areas overlap. Do not use vibrators to move concrete. Insert
vibrators vertically and slowly withdraw from the concrete. The
vibration shall be of sufficient duration and intensity to thoroughly
consolidate the concrete but not to cause segregation. Do not vibrate at
any one point long enough to cause localized areas of grout to form. Do
not vibrate reinforcement.

**(e) Underwater placement.** Underwater placement of concrete is
permitted only for seal concrete and drilled shafts. If other than seal
concrete is used, increase the minimum cement content by 10 percent. Use
tremies, concrete pumps, or other approved methods for placement.

**(1) Tremies.** Use watertight tremies, with a diameter of 10 inches or
more. Fit the top with a hopper. Use multiple tremies as required. Make
tremies capable of being rapidly lowered to retard or stop the flow of
concrete.

At the start of concrete placement, seal the discharge end and fill the
tremie tube with concrete. Keep the tremie tube full of concrete to the
bottom during placement. If water enters the tube, withdraw the tremie,
and reseal the discharge end. Maintain continuous concrete flow until
the placement is completed.

**(2) Concrete pumps.** Use pumps with a device at the end of the
discharge tube to seal out water while the tube is first being filled
with concrete. When concrete flow is started, keep the end of the
discharge tube full of concrete and below the surface of the deposited
concrete until placement has been completed.

Place underwater concrete continuously from start to finish in a dense
mass. Place each succeeding layer of concrete before the preceding layer
has taken initial set. Use more than one tremie or pump as necessary to
ensure compliance with this requirement. Keep the concrete surface as
horizontal as practicable. Do not disturb after placement. Maintain
still water at the point of deposit.

Dewater after test specimens cured under similar conditions indicate
that the concrete has sufficient strength to resist the expected loads.
Remove all laitance or other unsatisfactory material from the exposed
concrete.

**(f) Concrete railings and parapets.** Use smooth, tight-fitting, rigid
forms. Neatly miter corners. Place concrete railings and parapets after
the centering or falsework for the supporting span is released. Remove
forms without damaging the concrete. Finish all corners to be true,
clean-cut, and free from cracks, spalls, or other defects.

Cast precast railing members in mortar-tight forms. Remove precast
members from molds as soon as the concrete has sufficient strength to be
self-supporting. Protect edges and corners from chipping, cracking, and
other damage. Cure according to Subsection 552.15(b). The curing period
may be shortened, as approved, by using moist heat, type III portland
cement, or water reducing agents.

**552.12 Construction Joints.** Provide construction joints at locations
shown on the plans. Written approval is required for any additional
construction joints.

Extend reinforcing steel uninterrupted through construction joints. Do
not lap splice or mechanically splice reinforcing in the construction
joint. Embed lap splices or mechanical splices within the concrete. Do
not use dowels. At horizontal construction joints, place gauge strips
inside the forms along all exposed faces to produce straight joint
lines.

When the joint is between two fresh concrete placements, rough float the
first placement to thoroughly consolidate the surface and leave the
joint surface in a roughened condition. Keep the joint surface
saturated. Immediately before placing the new concrete, draw the forms
tightly against previously placed concrete and, where accessible,
thoroughly coat the joint surface with a very thin coating of cement
mortar.

When the joint is between existing concrete and a new placement,
abrasive blast clean or use other approved methods to remove all
laitance and foreign material, to expose clean aggregate, and to roughen
the joint surface. Before concrete placement, apply approved bonding
products to the joint surface according to the manufacturer's
recommendation.

**552.13 Expansion and Contraction Joints.**

**(a) Open joints.** Form open joints with a wooden strip, metal plate,
or other approved material. Remove the joint forming material without
chipping or breaking the corners of the concrete. Do not extend
reinforcement across an open joint.

**(b) Filled joints.** Cut premolded expansion joint filler to the shape
and size of the surface being jointed. Secure the joint filler on one
surface of the joint using galvanized nails or other acceptable means.
Splice according to the manufacturer\'s recommendations. After form
removal, remove and neatly cut all concrete or mortar that has sealed
across the joint. Fill all joint gaps 1/8 inch or wider with hot asphalt
or other approved filler. Place all necessary dowels, load transfer
devices, and other devices as shown on the plans or as directed.

**(c) Steel joints.** Fabricate plates, angles, or other structural
shapes accurately to conform to the concrete surface. Set joint opening
to conform to the ambient temperature at the time of concrete placement.
Securely fasten the joints to keep them in correct position. Maintain an
unobstructed joint opening during concrete placement.

**(d) Compression joint seals.** Use one-piece compression joint seals
for transverse joints and the longest practicable length for
longitudinal joints. Clean and dry joints and remove spalls and
irregularities. Apply a lubricant adhesive as a covering film to both
sides of the seal immediately before installation. Compress the seal and
place it in the joint as recommended by the manufacturer. Make sure the
seal is in full contact with the joint walls throughout its length.

Remove and discard all seals that are twisted, curled, nicked or
improperly formed. Remove and reinstall joint seals that elongate more
than 5 percent of their original length when compressed. Remove all
excess lubricant-adhesive before it dries.

**(e) Elastomeric expansion joint seal.** Install the joint according to
the manufacturer\'s recommendations and in conformance with the plans.

**552.14 Finishing Plastic Concrete.** Strike off concrete surfaces that
are not placed against forms. Float finish the concrete surface. Remove
any laitance or thin grout. Carefully tool all nonchamfered edges with
an edger. Leave edges of joint filler exposed.

Protect the surface from rain damage.

Provide at least two work bridges capable of supporting the workers and
equipment during placement, curing, and finishing operations without
sagging or vibrating. Place the work bridges at a reasonable height
above the concrete surface to not impede worker performance and not
touch the finished or fresh concrete surface.

**(a) Striking off and floating.** For bridge decks or top slabs of
structures serving as finished pavements, use an approved power driven
finishing machine equipped with a screed that oscillates in a transverse
direction. If approved, use hand-finishing methods for irregular areas
where the use of a machine is impractical.

Strike off all surfaces using equipment supported by and traveling on
screed rails or headers. Do not support rails within the limits of the
concrete placement without approval.

Set rails or headers on nonyielding supports so the finishing equipment
operates without interruption over entire surface being finished. Extend
rails beyond both ends of the scheduled concrete placement a sufficient
distance to enable finishing machine to finish the concrete being
placed.

Set rails the entire length of steel girder superstructures.

Adjust rails, headers, and strike-off equipment to the required profile
and cross-section allowing for anticipated settlement, camber, and
deflection of falsework.

Before beginning delivery and placement of concrete, operate the
finishing machine over the entire area to be finished to check for
excessive rail deflections, deck thickness, reinforcing steel cover, and
to verify proper operation of equipment. Make necessary corrections
before concrete placement begins.

After placing the concrete, operate finishing machine over the concrete
as needed to obtain the required profile and cross-section. Keep a
slight roll of excess concrete in front of the cutting edge of the
screed at all times. Maintain this excess of concrete to the end of the
pour or form and then remove and waste it. Adjust rails or headers as
necessary to correct for unanticipated settlement or deflection.

Remove rail supports embedded in the concrete to at least 2 inches below
the finished surface. Clean the voids of dust and debris using
compressed air or other means. Apply approved bonding material in the
voids. Fill the voids with fresh concrete of the same type and property
as previously placed. Finish the surface with a float, roller or other
approved device as necessary to remove all local irregularities.

Remove all excess water, laitance, or foreign material brought to the
surface using a squeegee or straightedge drawn from the center of the
slab towards either edge. Do not apply water to the surface of the
concrete during finishing operations.

**(b) Straightedging.** Check all slab and sidewalk surfaces. Check the
entire surface parallel to the centerline of the bridge with a 10-foot
metal straightedge. Overlap the straightedge at least half the length of
the previous straightedge placement.

Correct deviations in excess of 1/8 inch from the testing edge of the
straightedge. For deck surfaces that are to receive an overlay, correct
deviations in excess of 1/4 inch.

**(c) Texturing.** Finish after floating or at a time when finishing
operations will not displace aggregate. Produce a skid-resistant surface
texture on all driving surfaces by grooving. Use one of the following
finishes or a combination thereof for other surfaces as required.

**(1) Grooved finish.** Use a float having a single row of fins or an
approved machine designed specifically for sawing grooves in concrete
pavements. Space fins 1/2 to 3/4 inch on centers. Make the grooves 1/16
to 3/16 inch wide and 1/8 to 3/16 inch deep. Groove perpendicular to the
centerline without tearing the concrete surface or loosening surface
aggregate.

If grooves are sawn, cut the grooves approximately 1/4 inch wide at a
spacing of 1/2 to 1 inch.

On bridge decks, discontinue grooving 12 inches from curb face and
provide a longitudinal troweled finish on the surface of gutters.

**(2) Sidewalk finish.** Strike off the surface using a strike board and
then float the surface. Use an edging tool on edges and expansion
joints. Broom the surface using a broom with stiff bristles, broom
perpendicular to the centerline from edge to edge with adjacent strokes
slightly overlapped. Produce regular corrugations not over 1/8 inch in
depth without tearing the concrete. While the concrete is plastic,
correct porous spots, irregularities, depressions, small pockets, and
rough spots. Groove contraction joints at the required interval using an
approved grooving tool.

**(3) Troweled and brushed finish.** Use a steel trowel to produce a
slick, smooth surface free of bleed water. Brush the surface with a fine
brush using parallel strokes.

**(4) Exposed aggregate finish.** Strike off the surface using a strike
board and then float the surface. Use an edging tool on all transverse
and longitudinal joints that are against forms or existing pavement. Do
not edge transverse joints in a continuous lane pour or longitudinal
joints in a continuous dual lane pour.

As soon as the concrete hardens sufficiently to prevent particles of
gravel from being dislodged, broom the surface. Use stiff brushes
approved by the CO. Exercise care to prevent marring of the surface and
cracking or chipping of slab edges or joints. If approved by the CO,
apply a light spray of retardant to the unfinished surface to facilitate
this work.

First, broom transversely across the pavement. Pull the loosened
semi-stiff mortar entirely off the pavement. Remove the mortar from all
adjacent pavements. Then broom parallel to the pavement centerline.
Continue this operation until a sufficient amount of coarse aggregate is
exposed. Other methods of aggregate exposure, such as using a water
spray attachment on a special exposed aggregate broom, will be permitted
if satisfactory results are demonstrated.

After curing according to Subsection 552.15(b) or (c), wash the surface
with brush and water to remove all laitance and cement from the exposed
coarse aggregate.

**(d) Surface underneath bearings.** Finish all bearing surfaces to
within 1/8 inch of plan elevation. When a masonry plate is to be placed
directly on the concrete or on filler material less than 1/8 inch thick,
finish the surface with a float to an elevation slightly above plan
elevation. After the concrete is set, grind the surface as necessary to
provide a full and even bearing.

When a masonry plate is to be set on filler material between 1/4 and 1/2
inch thick, finish the surface with a steel trowel. Finish or grind the
surface so that it does not vary from a straightedge in any direction by
more than 5/8 inch.

When a masonry plate is to be set on filler material greater than 1/2
inch thick or when an elastomeric bearing pad is to be used, finish the
surface to a plane surface free of ridges.

When required under a masonry plate or elastomeric bearing pad, use
mortar in the proportions of 1 part masonry or hydraulic cement and 1.5
parts clean sand. Thoroughly mix sand and cement before adding water.
Mix only enough mortar for immediate use. Discard mortar that is more
than 45 minutes old. Do not re-temper mortar. Cure mortar at least 3
days and do not apply loads to mortar for at least 48 hours. Do not mix
and use mortar during freezing conditions. Mortar sand shall conform to
AASHTO M 45. Proprietary products may be used with approval.

**(e) Surface underneath waterproofing membrane deck seal.** Surfaces
that are to be covered with a waterproofing membrane deck seal shall not
be coarse textured, but shall be finished to a smooth surface and free
of ridges and other projections.

**552.15 Curing Concrete.** Begin curing immediately after the free
surface water has evaporated and the finishing is complete. If the
surface of the concrete begins to dry before the selected cure method
can be implemented, keep concrete surface moist using a fog spray
without damaging the surface.

Keep surfaces to be rubbed moist after forms are removed. Cure
immediately following the first rub.

Cure the top surfaces of bridge decks using the liquid membrane curing
compound method combined with the water method. Apply liquid membrane
curing compound immediately after finishing. Apply the water cure within
4 hours after finishing.

Cure all concrete uninterrupted for at least 7 days. If pozzolans in
excess of 10 percent by mass of the hydraulic cement is used in the mix,
cure uninterrupted for at least 10 days.

**(a) Forms inplace method.** For formed surfaces, leave the forms
inplace without loosening. If forms are removed during the curing period
to facilitate rubbing, only strip forms from those areas able to be
rubbed during the same shift. During rubbing, keep the surface of the
exposed concrete moist. After the rubbing is complete, continue curing
process using the water method for the remainder of the curing period.

**(b) Water method.** Keep the concrete surface continuously wet by
ponding, spraying, or covering with material that is kept continuously
and thoroughly wet. Covering material may consist of cotton mats,
multiple layers of burlap, or other approved material that does not
discolor or otherwise damage the concrete.

Cover the covering material with a waterproof sheet material that
prevents moisture loss from the concrete. Use the widest sheets
practical. Lap adjacent sheets at least 6 inches, and tightly seal all
seams with pressure sensitive tape, mastic, glue, or other approved
methods. Secure all material so that wind does not displace it.
Immediately repair sheets that are broken or damaged.

**(c) Liquid membrane curing compound method.** Do not use the liquid
membrane method on surfaces to receive a rubbed finish. Use on
construction joint surfaces is permitted only if the compound is removed
by sandblasting before placement of concrete against the joint.

Use type 2, white-pigmented, liquid membrane only on the top surfaces of
bridge decks or on surfaces not exposed to view in the completed work.
Use type 1 or 1-D clear curing compounds on other surfaces.

Mix membrane curing solutions containing pigments before use. Continue
to agitate during application. Use equipment capable of producing a fine
spray. Apply the curing compound at a minimum rate of 1 gallon per 150
square feet in one or two uniform applications. If the solution is
applied in 2 applications, follow the first application with the second
application within 30 minutes, and apply at right angles to the first
application.

If the membrane is damaged by rain or other means during the curing
period, immediately apply a new coat over the damaged areas.

**(d) Steam curing method.** Prepare and cure precast members according
to ACI 517.2R.

**552.16 Finishing Formed Concrete Surfaces.** Remove and replace or
repair, as approved, all rock pockets or honeycombed concrete. Finish
sound, formed concrete surfaces as follows.

**(a) Class 1 --- Ordinary surface finish.** Finish the following
surfaces with a class 1, ordinary surface finish:

**(1)** Under surfaces of slab spans, box girders, filled spandrel arch
spans, and the roadway deck slab between superstructure girders;

**(2)** Inside vertical surface or T-girders of superstructures; and

**(3)** Surfaces to be buried and culvert surfaces above finished ground
that are not visible from the traveled way or a walkway.

Begin finishing as soon as the forms are removed. Remove fins and
irregular projections from all surfaces that are exposed or will be
waterproofed. Remove bulges and offsets with carborundum stones or
discs. Remove localized, poorly‑bonded rock pockets or honeycombed
concrete, and replace with sound concrete or packed mortar in an
approved manner.

Clean and point all form tie cavities, holes, broken corners and edges,
and other defects. Saturate the area with water. Finish the area with
mortar that is less than 1‑hour-old. After the mortar is set, rub it (if
required) and continue curing. Match exposed surfaces to surrounding
concrete.

Carefully tool and remove free mortar and concrete from construction and
expansion joints. Leave joint filler exposed for its full length with
clean, true edges.

Rub or grind bearing surfaces on piers and abutments to the specified
elevation and slope.

If the final finished surface is not true and uniform, rub it according
to (b) below.

**(b) Class 2 --- Rubbed finish.** Finish the following surfaces with a
class 2, rubbed finish:

**(1)** All surfaces of bridge superstructures except those surfaces
designated to receive a class 1 or other finish;

**(2)** All surfaces of bridge piers, piles, columns and abutments, and
retaining walls above finished ground and to at least 12 inches below
finished ground;

**(3)** All surfaces of open spandrel arch rings, spandrel columns and
abutment towers;

**(4)** All surfaces of pedestrian undercrossings except floors and
surfaces to be covered with earth;

**(5)** Surfaces above finished ground of culvert headwalls and endwalls
when visible from the traveled way or walkway;

**(6)** Inside surfaces of culvert barrels higher than 4 feet that are
visible from the traveled way. Finish for a distance inside the barrel
at least equal to the height of the culvert; and

**(7)** All surfaces of railings.

Complete a class 1 finish according to paragraph (a) above. Saturate the
concrete surface with water. Rub the surface with a medium coarse
carborundum stone using a small amount of mortar on its face. Use mortar
composed of cement and fine sand mixed in the same proportions as the
concrete being finished. Continue rubbing until form marks, projections,
and irregularities are removed and a uniform surface is obtained. Leave
the paste produced by this rubbing in place.

After other work, which could affect the surface, is complete, rub with
a fine carborundum stone, and water until the entire surface has a
smooth texture and uniform color. After the surface has dried, rub it
with burlap to remove loose powder. Leave it free from all unsound
patches, paste, powder, and objectionable marks.

**(c) Class 3 --- Tooled finish.** Let the concrete set for at least 14
days or longer if necessary to prevent the aggregate particles from
being *\"picked\"* out of the surface. Use air tools such as a bush
hammer, pick, or crandall. Chip away the surface mortar, and break the
aggregate particles to expose a grouping of broken aggregate particles
in a matrix of mortar.

**(d) Class 4 --- Sandblasted finish.** Let the concrete cure for at
least 14 days. Protect adjacent surfaces that are not to be sandblasted.
Sandblast a small test area for approval before proceeding. Use hard,
sharp sand to produce an even fine-grained surface in which the mortar
is cut away leaving the aggregate exposed. Do not remove mortar beyond
one-third the diameter of the coarse aggregate.

**(e) Class 5 --- Wire brushed or scrubbed finish.** Begin as soon as
the forms are removed. Scrub the surface with stiff wire or fiber
brushes using a solution of muriatic acid. Mix the solution in the
proportion of 1 part acid to 4 parts water. Scrub until the cement film
or surface is completely removed and the aggregate particles are
exposed. Leave an evenly pebbled texture having the appearance of fine
granite to coarse conglomerate depending upon the size and grading of
aggregate. Wash the entire surface with water containing a small amount
of ammonia.

**(f) Class 6 --- Color finish.** Build a sufficient number of 2 by
4-foot concrete color sample panels to obtain a color acceptable to the
CO. Protect the approved color sample panel at all times during the
work. Color all designated surfaces to match the color of the approved
sample.

Complete a class 1 finish according to (a) above. Do not apply the color
finish until all concrete placement for the structure is complete.
Remove all dust, foreign matter, form oil, grease, and curing compound
with a 5 percent solution of trisodium phosphate and then rinse the
concrete surface with clean water.

Use paper, cloth, or other means to protect surfaces not to be color
finished. Apply the finish to a dry concrete surface when the surface
temperature is 40 ºF or higher and the air temperature in the shade is
anticipated to be 40 ºF or higher during the 24 hours following
application.

Apply the color finish according to the manufacturer\'s recommendations.
Spray, brush, or roll on the first coat of penetrating sealer and color
base. Spray, brush, or roll on the finish coat after the first coat has
thoroughly dried. Apply finish to provide a uniform, permanent color,
free from runs and sags to the surfaces.

Clean concrete areas not intended to be covered by the finish using an
approved method.

**(g) Class 7 --- Bush hammered finish.** Do not use mortar blocks or
wires to set reinforcing steel near the formed surface of areas to be
bush hammered. Let the concrete cure for at least 14 days. Bush hammer a
small test area for approval before proceeding. Adjust the work
procedures to produce a satisfactory finish, and use those same
procedures to bush hammer the designated area.

**552.17 Concrete Anchorage Devices.** Use chemical, grouted, or
cast-in-place concrete anchorage devices for attaching equipment or
fixtures to concrete.

Furnish the following for approval:

**(a)** Concrete anchorage device sample;

**(b)** Manufacturer\'s installation instructions; and

**(c)** Material data and certifications.

Fabricate all metal parts of the anchorage devices from stainless steel
or from steel protected with a corrosion resistant metallic coating that
does not react chemically with concrete. Supply anchorage devices
complete with all hardware.

For chemical or grouted anchors, conduct a system approval test on one
anchor on the project, not to be incorporated in the work. Conduct a
static load test according to ASTM E 488. Demonstrate that the anchorage
device can withstand a sustained direct tension test load not less than
the values shown in Table 552-7 for a period of at least 48 hours with
movement not to exceed 1/32 inch. Also demonstrate that when loaded to
failure, the anchor device demonstrates a ductile failure of the anchor
steel, not a failure of the chemical, grout, or concrete.

Table 552-7

Sustained Load Test Values

  ----------------------------------- -----------------------------------
  **Anchorage Device Stud Size        **Tension Test Load (pounds)**
  (inches)**                          

  3/4                                 5,000

  5/8                                 4,100

  1/2                                 3,200

  3/8                                 2,100

  1/4                                 1,000
  ----------------------------------- -----------------------------------

Install concrete anchorage devices as recommended by the device
manufacturer and so that the attached equipment or fixtures bear firmly
against the concrete. Torque installed nuts to the values specified in
Table 552-8 unless otherwise specified in the manufacturer\'s
instructions. Set bearing anchor bolts according to the requirements of
Section 564.

In the presence of the CO, proof load a random sample of at least 10
percent of the anchors to 90 percent of the yield stress of the steel.
If any anchor fails, reset the failed anchor and proof load the reset
anchor and 100 percent of all remaining anchors. The proof load may be
applied by torquing against a load indicator washer, applying a direct
tension load to the anchor, or another method approved by the CO. After
proof loading, release the load on the anchor and retighten the nuts to
the torque specified in Table 552-8 or according to the manufacturer\'s
instructions.

Table 552-8

Torque for Anchorage Devices

+-----------------------------------+----------------------------------+
| **Anchorage Device Stud Diameter  | **Torque**                       |
| (inches)**                        |                                  |
|                                   | **(foot** • **pounds)**          |
+-----------------------------------+----------------------------------+
| 3/4                               | 125                              |
+-----------------------------------+----------------------------------+
| 5/8                               | 90                               |
+-----------------------------------+----------------------------------+
| 1/2                               | 60                               |
+-----------------------------------+----------------------------------+
| 3/8                               | 35                               |
+-----------------------------------+----------------------------------+
| 1/4                               | 10                               |
+-----------------------------------+----------------------------------+

**552.18** **Loads on New Concrete Structures.** Do not allow traffic on
concrete bridge decks until all deck concrete has attained the design
compressive strength and has been in place 14 days or longer.
Construction loads less than 4000 pounds, may be placed on the deck 7
days after the concrete is placed and the concrete in the entire span
has attained a compressive strength of at least 70 percent of the
specified design strength.

For precast concrete multi-beam sections, do not allow vehicles on any
span until the grout has attained a strength of 3,000 pounds per square
inch and tie rods have been tightened.

For post-tensioned concrete structures, do not allow vehicles over 4.500
pounds on any span until the prestressing steel for that span is
tensioned, grouted, and cured, the grout has obtained a strength of
3,000 pounds per square inch, and the tie rods are tightened. Vehicles
weighing less than 4,500 pounds may be permitted on a span provided the
mass of the vehicle was included in the falsework design.

**552.19 Acceptance.** See Table 552-9 for sampling and testing
requirements and the acceptance quality characteristic category.

Material for concrete will be evaluated under Subsections 106.02 and
106.03. Furnish a production certification for the hydraulic cement.

The concrete mixture\'s slump, air content, unit mass, and temperature
will be evaluated under Subsections 106.02 and 106.04.

Concrete compressive strength will be evaluated under Subsection 106.05.
The lower specification limit is the minimum required compressive
strength at 28 days (f~c~') specified in the contract. A single
compressive strength test result is the average result from 2 cylinders
cast from the same load and tested at 28 days.

Remove and replace concrete if the compressive strength test results are
less than 90 percent of specified design strength (f'c) at the specified
test age.

Construction (including batching, placing, finishing, and curing
concrete) of concrete structures will be evaluated under Subsections
106.02 and 106.04.

Falsework and forms will be evaluated under Section 562.

Measurement

**552.20** Measure the Section 552 items listed in the bid schedule
according to Subsection 109.02 and the following as applicable.

Measure structural concrete and seal concrete by the cubic yard in the
structure.

Payment

**552.21** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 552 pay items listed in the bid
schedule except the structural concrete unit bid price will be adjusted
according to Subsection 106.05. Payment will be full compensation for
the work prescribed in this Section. See Subsection 109.05.

Payment for a structural concrete will be made at a price determined by
multiplying the unit bid price by the compressive strength pay factor.

+-------+----------+-----------+-----------+------------+------+---+
| Table | **Rep    | Before    | Before    | Before     | "    | " |
| 552-9 | orting** | producing | producing | batching   |      |   |
|       |          |           |           |            |      |   |
| Sam   | **Time** |           |           |            |      |   |
| pling |          |           |           |            |      |   |
| and   |          |           |           |            |      |   |
| Te    |          |           |           |            |      |   |
| sting |          |           |           |            |      |   |
| Re    |          |           |           |            |      |   |
| quire |          |           |           |            |      |   |
| ments |          |           |           |            |      |   |
+-------+----------+-----------+-----------+------------+------+---+
|       | *        | Yes       | Yes       | Yes, when  | "    | " |
|       | *Split** |           |           | requested  |      |   |
|       |          |           |           |            |      |   |
|       | **       |           |           |            |      |   |
|       | Sample** |           |           |            |      |   |
+-------+----------+-----------+-----------+------------+------+---+
|       | **Point  | Source of | Source of | Flowing    | "    | " |
|       | of       |           |           | aggregate  |      |   |
|       | Sa       | material  | material  | stream     |      |   |
|       | mpling** |           |           | (bin,      |      |   |
|       |          |           |           |            |      |   |
|       |          |           |           | belt,      |      |   |
|       |          |           |           | discharge  |      |   |
|       |          |           |           | conveyor   |      |   |
|       |          |           |           | belt, or   |      |   |
|       |          |           |           | stockpile) |      |   |
+-------+----------+-----------+-----------+------------+------+---+
|       | **Sa     | 1 per     | 1 per mix | 1 per day  | ---  | - |
|       | mpling** | material  | design    |            |      | - |
|       |          | type      |           |            |      | - |
|       | **Fre    |           |           |            |      |   |
|       | quency** |           |           |            |      |   |
+-------+----------+-----------+-----------+------------+------+---+
|       | **Test   | AASHTO M  | S         | AASHTO T   | AA   | A |
|       | Methods  | 80        | ubsection | 27 &       | SHTO | A |
|       | Specific |           | 552.03    |            | T 27 | S |
|       | ations** |           |           | T 11       |      | H |
|       |          |           |           |            |      | T |
|       |          |           |           |            |      | O |
|       |          |           |           |            |      | T |
|       |          |           |           |            |      | 2 |
|       |          |           |           |            |      | 2 |
|       |          |           |           |            |      | 5 |
+-------+----------+-----------+-----------+------------+------+---+
|       | **Ca     | ---       | ---       | ---        | ---  | - |
|       | tegory** |           |           |            |      | - |
|       |          |           |           |            |      | - |
+-------+----------+-----------+-----------+------------+------+---+
|       | **       | Quality   | All       | Gradation  | Fine | M |
|       | Characte |           |           |            | ness | o |
|       | ristic** |           |           |            |      | i |
|       |          |           |           |            | mod  | s |
|       |          |           |           |            | ulus | t |
|       |          |           |           |            |      | u |
|       |          |           |           |            |      | r |
|       |          |           |           |            |      | e |
|       |          |           |           |            |      | t |
|       |          |           |           |            |      | e |
|       |          |           |           |            |      | s |
|       |          |           |           |            |      | t |
+-------+----------+-----------+-----------+------------+------+---+
|       | **Type   | Measured  | Measured  | Measured   |      |   |
|       | of       | and       | and       | and tested |      |   |
|       | Ac       | tested    | tested    |            |      |   |
|       | ceptance |           |           | for        |      |   |
|       | (Subse   | for       | for       | c          |      |   |
|       | ction)** | co        | co        | onformance |      |   |
|       |          | nformance | nformance | (106.04)   |      |   |
|       |          |           |           |            |      |   |
|       |          | (106.04 & | (106.04 & |            |      |   |
|       |          | 105)      | 105)      |            |      |   |
+-------+----------+-----------+-----------+------------+------+---+
|       | **       | Aggregate | Concrete  | Produced   |      |   |
|       | Material | source    |           | aggregate  |      |   |
|       | or       | quality   | co        | (fine &    |      |   |
|       | P        |           | mposition | coarse)    |      |   |
|       | roduct** | (703.02)  |           |            |      |   |
|       |          |           | (mix      |            |      |   |
|       |          |           | design)   |            |      |   |
+-------+----------+-----------+-----------+------------+------+---+

<table>
<colgroup>
<col style="width: 10%" />
<col style="width: 14%" />
<col style="width: 13%" />
<col style="width: 10%" />
<col style="width: 7%" />
<col style="width: 8%" />
<col style="width: 14%" />
<col style="width: 5%" />
<col style="width: 5%" />
<col style="width: 5%" />
<col style="width: 5%" />
</colgroup>
<tbody>
<tr class="odd">
<td rowspan="9"><p>Table 552-9 (continued)</p>
<p>Sampling and Testing Requirements</p></td>
<td><strong>Reporting Time</strong></td>
<td><p>Upon</p>
<p>completing tests</p></td>
<td>“</td>
<td>“</td>
<td>“</td>
<td>See Subsection 552.09(b)(4)</td>
<td rowspan="9">(1) Sample according to AASHTO T 141 except composite
samples are not required.</td>
<td rowspan="9">(2) Cast at least 4 compressive strength test cylinders
and carefully transport the cylinders to the job site curing
facility.</td>
<td rowspan="9">(3) A single compressive strength test result is the
average result from 2 cylinders cast from the same lead and tested at 28
days.</td>
<td rowspan="9">(4) Deliver cylinders to designated laboratory for
test.</td>
</tr>
<tr class="even">
<td><p><strong>Split</strong></p>
<p><strong>Sample</strong></p></td>
<td>—</td>
<td>—</td>
<td>—</td>
<td>—</td>
<td>Note 4</td>
</tr>
<tr class="odd">
<td><strong>Point of Sampling</strong></td>
<td><p>Point of</p>
<p>discharge</p></td>
<td>“</td>
<td>“</td>
<td>“</td>
<td><p>Discharge stream at point of</p>
<p>placing</p></td>
</tr>
<tr class="even">
<td><p><strong>Sampling</strong></p>
<p><strong>Frequency</strong></p></td>
<td>1 per load</td>
<td>“</td>
<td>“</td>
<td>“</td>
<td>1 set per 30 yd<sup>3</sup> but not less than 1 per day</td>
</tr>
<tr class="odd">
<td><strong>Test Methods Specifications</strong></td>
<td>AASHTO T 121</td>
<td>AASHTO T 152 or AASHTO T 196</td>
<td>AASHTO T 119</td>
<td>Field measured</td>
<td><p>AASHTO T 23 &amp;</p>
<p>T 22</p></td>
</tr>
<tr class="even">
<td><strong>Category</strong></td>
<td>—</td>
<td>—</td>
<td>—</td>
<td>—</td>
<td>II</td>
</tr>
<tr class="odd">
<td><strong>Characteristic</strong></td>
<td>Unit mass</td>
<td>Air content</td>
<td>Slump</td>
<td>Temperature</td>
<td>Compressive strength<sup>( 3)</sup></td>
</tr>
<tr class="even">
<td><strong>Type of Acceptance (Subsection)</strong></td>
<td colspan="4"><p>Measured and tested</p>
<p>for conformance (106.04)</p></td>
<td><p>Statistical</p>
<p>(106.05)</p></td>
</tr>
<tr class="odd">
<td><strong>Material or Product</strong></td>
<td colspan="4">Concrete (552.09(b)(3))</td>
<td>Structural concrete (552.09(b)(3))</td>
</tr>
</tbody>
</table>

## Section 553. --- PRESTRESSED CONCRETE

Description

**553.01** This work consists of prestressing precast or cast-in-place
concrete by furnishing, placing, and tensioning prestressing steel. It
also includes installing all precast, prestressed members except piling.

Material

**553.02** Conform to the following Section and Subsections:

Anchorage devices 722.01

Concrete 552

Elastomeric bearing pads 717.10

Grout for post-tensioned structures 725.22(d)

Prestressing steel 709.03

Reinforcing steel 709.01

Construction Requirements

**553.03** **Method Approval.** Perform prestressing by either
pretensioning or post-tensioning methods. If a method is proposed that
is not in the contract, submit detailed drawings of the method,
material, and equipment proposed for approval at least 30 days before
starting prestressing. Show the following:

**(a)** Method and sequence of stressing;

**(b)** Complete specifications, details, and test results for the
prestressing steel and anchoring devices;

**(c)** Anchoring stresses;

**(d)** Arrangement of the prestressing steel in the members;

**(e)** Tendon elongation calculations for jacking procedures to be
used;

**(f)** Number, spacing, and method of draping pretensioned strands;

**(g)** Other substantiating calculations for the prestressing method;

**(h)** Type of tendon ducts for post-tensioning;

**(i)** Pressure grouting material and equipment for post-tensioning;
and

**(j)** Samples of wire or strand taken according to Subsection 709.03.

For on-site casting, submit drawings showing anticipated leveling or
alterations to the site. After completion of casting, clear the site of
equipment and rubbish, and restore it to an acceptable condition.

**553.04 Prestressing Steel.** Use prestressing steel that is bright and
free of corrosion, dirt, grease, wax, scale, rust, oil, or other foreign
material that may prevent bond between the steel and the concrete. Do
not use prestressing steel that has sustained physical damage or is
pitted.

One splice per strand is permitted when single strand jacking is used.
When multi-strand jacking is used, splice all the strands or no more
than 10 percent of the strands. Use strands having similar properties,
from the same source, and having the same "twist" or "lay." Locate
splices outside the casting bed and between members.

Do not weld or ground welding equipment on forms or other steel in the
member after the prestressing steel is installed.

Failure of one wire in a 7-wire prestressing strand is acceptable if 85
percent of the required tension load is attained before failure and if
the failed strand does not constitute more than 2 percent of the total
area of strands in an individual beam or girder.

Extend bars using couplers which, when assembled, have a tensile
strength not less than the tensile strength of the bars.

Protect all prestressing steel against physical damage, rust, or
corrosion at all times. Do not use damaged prestressing steel.

Package prestressing steel to protect it from physical damage and
corrosion during shipping and storage. Place a corrosion inhibitor in
the package. Use a corrosion inhibitor that has no deleterious effect on
the steel, concrete, or bond strength of steel to concrete. Immediately
replace or restore damaged packaging.

Mark the shipping package with a statement that the package contains
high-strength prestressing steel and a warning to use care in handling.
Identify the type, kind, and amount of corrosion inhibitor used,
including the date when placed, safety regulations, and instructions for
use. Assign a lot number and tag, for identification purposes, to all
wire, strand, anchorage assemblies, or bars shipped to the site.

**553.05 Concrete.** Construct prestressed concrete according to Section
552. Construct reinforcing steel according to Section 554.

Make at least 2 release strength test cylinders according to AASHTO T 23
in addition to those required to determine the 28-day compressive
strength. Cure the release strength test cylinders with the concrete
member they represent.

Rough cast the top surface of members against which concrete will be
cast. Surfaces that are to be covered with a waterproofing membrane deck
seal are not to be coarse textured but finished to a smooth surface free
of ridges and other projections.

Cure the girder in a saturated atmosphere of at least 90 percent
relative humidity. Cure time may be shortened by heating the outside of
impervious forms with radiant heat, convection heat, conducted steam, or
hot air.

Apply radiant heat by means of pipes circulating steam, hot oil, hot
water, or electric heating elements. Inspect casting beds to ensure
uniform heat application. Use a suitable enclosure to contain the heat.
Minimize moisture loss by covering all exposed concrete surfaces with
plastic sheeting or liquid membrane curing compound according to
Subsection 552.15. Sandblast curing compound from all surfaces to which
concrete will be bonded.

Envelop the entire surface with saturated steam. Completely enclose the
casting bed with a suitable type of housing, tightly constructed to
prevent the escape of steam and exclude outside air. Use steam at 100
percent relative humidity. Do not apply the steam directly to the
concrete.

With hot air, the CO will approve the method to envelop and maintain the
girder in a saturated atmosphere. Never allow dry heat to touch the
girder surface.

With all heat curing methods:

**(a)** Keep all unformed girder surfaces in a saturated atmosphere
throughout the curing time.

**(b)** Embed a thermocouple (linked with a thermometer accurate to ±5
ºF) 6 to 8 inches from the top or bottom of the girder on its centerline
and near its midpoint.

**(c)** Monitor with a recording sensor (accurate to ±5 ºF) arranged and
calibrated to continuously record, date, and identify concrete
temperature throughout the heating cycle.

**(d)** Make the temperature record available to the CO.

**(e)** Heat concrete to no more than 100 ºF during the first 2 hours
after placing concrete, and increase the temperature no more than 25 ºF
per hour to a maximum of 175 ºF.

**(f)** Cool concrete, after curing is complete, no more than 25 ºF per
hour, to 100 ºF.

**(g)** Keep the temperature of the concrete above 60 ºF until the
girder reaches release strength.

Cure precast, prestressed members until the concrete has attained the
release compressive strength, required by the contract. The average
strength of 2 test cylinders shall be greater than the minimum required
strength. The individual strength of any one cylinder shall not be more
than 5 percent below the required strength.

**553.06 Tensioning.** Use hydraulic jacks to tension prestressing
steel. Use a pressure gauge or load cell for measuring jacking force.

Calibrate measuring devices at least once every 6 months or if they
appear to be giving erratic results. Calibrate the jack and gauge as a
unit with the cylinder extension in the approximate position that it
will be at final jacking force. Keep a certified calibration chart with
each gauge.

If a pressure gauge is used, do not gauge loads less than 1/4 nor more
than 3/4 of the total graduated capacity of the gauge, unless
calibration data clearly establishes consistent accuracy over a wider
range. Use a pressure gauge with an accurate reading dial at least
6 inches in diameter.

Measure the force induced in the prestressing steel using calibrated
jacking gauges, load cells, or a calibrated dynamometer. Take elongation
measurements of the prestressing steel. Determine the required
elongation from average load-elongation curves for the prestressing
tendons used.

For pre-tensioned members, if there is a discrepancy between the gauge
pressure and elongation of more than 5 percent in tendons over 50 feet
in length or 7 percent in tendons of 50 feet or less in length determine
the source of error before proceeding. Do not allow discrepancies in
post-tensioned members to exceed 7 percent.

If the jacking system is equipped with an automatic release valve that
closes when the required prestressing force is reached, strand
elongation measurements are only required for the first and last tendon
tensioned and for at least 10 percent of the remaining tendons.

If a load cell is used, do not use the lower 10 percent of the
manufacturer\'s rated capacity of the load cell to determine the jacking
force.

Do not exceed a temporary tensile stress of 80 percent of the specified
minimum ultimate tensile strength of the prestressing steel. Anchor
prestressing steel at an initial stress that will result in the
retention of a working stress after all losses of not less than those
required.

For pretensioned members, do not allow the initial release stress after
seating, and before other losses, to exceed 70 percent of the specified
minimum ultimate tensile strength of the prestressing steel for
stress-relieved strands and 75 percent for low-relaxation strands. For
post-tensioned members, do not allow the initial release stress after
seating to exceed 70 percent of the specified minimum ultimate tensile
strength of the prestressing steel.

**553.07 Pretensioned Members.** Cast pretensioned members to the
tolerances shown in Table 553-1.

**(a) Prestressing steel.** Protect prestressing steel placed in the
stressing bed from contamination and corrosion if the stressing bed is
to be exposed to weather for more than 36 hours before encasement in
concrete.

Free all strands of kinks or twists. Accurately hold prestressing steel
in position and tension according to Subsection 553.06. Do not allow
strands to unwind more than one turn. Keep a record of the jacking force
and elongation measurements after the strands are tensioned to 20
percent of final jacking force.

Tension prestressing steel to the required stress. Include in elongation
computations strand anchorage slippage, splice slippage, in place
horizontal movement of the structural member during prestressing
operations, and prestressing steel temperature changes between the time
of tensioning and the time when the concrete takes its initial set. All
computations must be prepared by a professional engineer.

Maintain the prestress bed forms, strands, and reinforcement bar
temperature within 25 ºF of the temperature of the concrete to be placed
in the forms. Support strands with rollers at points of direction change
when strands are tensioned in a draped position. Use free-running
rollers with minimal friction. Initially, when strands are tensioned and
then pulled into the draped position, tension to no more than the
required tension minus the increased tension due to forcing the strand
to a draped profile. If the load in a draped strand at the dead end, as
determined by elongation measurements, is less than 95 percent of the
jack load, tension the strand from both ends of the bed. Make the load,
as computed from the sum of elongations produced by jacking at both
ends, agree within 5 percent of the jack load.

Within 3 hours before placing concrete, check the tension on the
prestressing strands. The method and equipment for checking the loss of
prestress shall be subject to approval by the CO. If strands are
tensioned individually, check each strand for loss of prestress.
Retension to the original computed jacking stress all strands that show
a loss of prestress in excess of 3 percent. If strands are tensioned in
a group, check the entire group for total loss of prestress. Release and
retension the entire group if the total prestress shows a loss in excess
of 3 percent or if any individual strand appears significantly different
from the rest of the strands in the group.

**(b) Releasing steel.** Release the prestress load to the concrete
after the concrete has attained its required release compressive
strength. Do not expose the concrete to temperatures below freezing for
at least 7 days after casting. Cut or release strands such that lateral
eccentricity of the prestress force is minimized. Cut prestressing steel
off flush with the end of the member.

**553.08 Storing, Transporting, and Erecting.** Do not ship prestressed
concrete members until concrete cylinder tests, manufactured of the same
concrete and cured under the same conditions as the members, indicate
that the concrete in each member has attained the minimum required
design strength and is at least 7-days-old except decked bulb-T sections
must be at least 10 days old.

Store, transport, and erect precast, prestressed girders, slab units,
and box units in the upright position with the points of support and
directions of the reactions, with respect to the member, approximately
the same as when the member is in its final position. Prevent cracking
or damage during storage, hoisting, and handling of the precast units.
Replace units damaged by improper storage or handling.

**553.09** **Post-Tensioned Members.** Construct post-tensioned members
to the tolerances shown in Table 553-1. Construct supporting falsework
so that the superstructure is free to lift off the falsework and shorten
during post-tensioning. Detail formwork left inside box girders to
support the roadway slab to offer minimum resistance to girder
shortening due to shrinkage and post-tensioning.

**(a) Ducts.** Use mortar-tight ducts that are sufficiently-rigid to
maintain their shape and alignment during concrete placement and grout
installation. Use ducts conforming to the following minimum wall
thicknesses:

**(1)** Metal duct (2⅝ inches diameter): 26 gage

**(2)** Metal duct (\> 2⅝ inches diameter): 24 gage

**(3)** High density polyethylene (HPDE): 14 gage

**(4)** High density polypropylene (HDPP): 14 gage

**(5)** Metal duct with bar tendons preassembled

with duct: 32 gage

For tendons composed of single prestressing bars, provide ducts with a
minimum internal duct diameter of at least 1/4 inch larger than the
outside diameter of the prestressing bar. For multiple wire, bar, or
strand tendons, provide a duct nominal internal cross-sectional area of
at least 2.25 times the net area of the prestressing steel. When tendons
are to be placed by the pull through method, provide a duct nominal
internal cross-sectional area of at least 2.5 times the net area of the
prestressing steel.

Make positive joints between duct sections. Do not make angles at the
joints. Use waterproof tape at the joints. Bend ducts without crimping
or flattening. Use ferrous metal or polyethylene couplings to connect
ducts to anchoring devices.

Protect ducts against crushing, excessive bending, dirt contamination,
and corrosive elements during transport, storage, and handling of ducts.

In case of duct damage, seal duct with tape, or splice a duct coupler
over the damaged section to form a seal that prevents cement paste from
entering the duct during the placement of concrete and to prevent
leakage during grouting operations.

Provide all ducts and anchorage assemblies with inlets for the injection
of grout into the duct after prestressing according to the *PTI Guide
Specification for Grouting of Post-Tensioned Structures*.

Provide all ducts with outlets to allow the escape of air, water, grout,
and bleed water according to the *PTI Guide Specification for Grouting
of Post-Tensioned Structures*.

Provide inlets and outlets with an inner diameter of at least 3/4 inch
for strand tendons and of at least 3/8 inch for single bar tendons.
Extend the length of outlets a sufficient distance out of the concrete
member to allow for the proper closing of the outlets.

Place inlets and outlets, at a minimum, in the following locations:

• The anchorage area of the tendon;

• All high points of the duct, when the vertical distance between the
highest and lowest point is more than 2 feet;

• Place an inlet at or near the lowest point of the tendon;

• Place a free draining outlet at all low points of the duct;

• At major changes in the cross-section of the duct, such as couplers
and anchorages; and

• An outlet at a distance less than 3 feet downstream from high point
outlets.

Show all inlet and outlet locations on drawings.

Provide positive mechanical shut-off valves for all inlets and outlets.
Provide inlets and outlets with valves, caps, or other devices capable
of withstanding the grouting pressure.

Securely fasten ducts in place to prevent movement. Maintain distances
from the forms by stays, blocks, ties, hangers, or other approved
supports. Use precast mortar blocks of approved shape and dimensions.
Separate layers of ducts by mortar blocks.

Space all duct supports according to the *PTI Guide Specification for
Grouting of Post-Tensioned Structures.* Cover the ends of ducts to
prevent the entry of water or debris.

Connect inlets and outlets to the duct with metallic or plastic
structural fasteners. Do not use components that react with the
concrete, cause corrosion of the prestressing steel, or contain water
soluble chlorides.

**(b) Placing concrete.** Where the end of a post-tensioned assembly
will not be covered by concrete, recess the anchoring devices so that
the ends of the prestressing steel and all parts of the anchoring
devices are at least 2 inches inside the end surface of the members.

Before placing concrete, demonstrate that all ducts are unobstructed.
Immediately after concrete placement, blow out the metal conduit with
compressed, oil-free air to break-up and remove all mortar in the
conduit before it hardens. Approximately 24 hours after the concrete
placement, flush the metal conduits with water containing lime (calcium
oxide) or slaked lime (calcium hydroxide) in the amount of 0.1 pounds
per gallon. Blow the water out with compressed, oil-free air.

For post-tensioned members that are to be steam cured, do not install
prestressing steel until curing is complete.

**(c) Anchorages and distribution.** Give at least 10 days advanced
notice before installing end fittings or heading wires.

When wires are used, provide an edge distance for any hole for
prestressing wire through a stressing washer, unthreaded bearing ring,
or plate of at least 1/4 inch from the root of any threads or the edge
of any ring, plate, or washer.

Anchor post-tensioned prestressing steel at the ends by means of
permanent type anchoring devices capable of developing not less than 95
percent of the ultimate tensile strength of the prestressing steel. If
the anchoring device is sufficiently large and is used in conjunction
with a steel grillage embedded in the concrete that effectively
distributes the anchor load to the concrete, the steel distribution
plates or assemblies may be omitted.

Enclose loop tendon anchorages in ducts for their entire length.

**(d) Prestressing steel.** Use a corrosion inhibitor to protect
prestressing steel installed in ducts before placing and curing of the
concrete. Use a corrosion inhibitor that does not adversely affect the
steel, concrete, or bond strength of the steel to concrete.

If prestressing steel is installed in the ducts within 10 days after
concrete curing, stressing, and grouting are completed, no corrosion
inhibitor is required.

**(e) Post-tensioning.** Wait at least 10 days after the last concrete
has been placed in the member or until tests on concrete cylinders
indicate that the concrete has attained the minimum compressive
strength. Demonstrate that the prestressing steel is free and unbonded
in the duct. Straighten wires if necessary to produce equal stress in
all wires, wire groups, or parallel lay tendons that are stressed
simultaneously. Remove all side forms for girders before
post-tensioning.

Record gauge pressures and prestressing steel elongation at all times
while tensioning prestressing steel and submit records.

Determine the friction loss in the prestressing process (i.e., the
difference between tension at the jack and minimum tension in the
prestressing steel) according to the AASHTO *Standard Specifications for
Highway Bridges.*

Use suitable shims or other approved devices to attain the specified
anchor set loss.

**(f) Grouting.** Provide Class A, B, C, or D grout as specified and
prestressing steel that is free of dirt, loose rust, grease, or other
deleterious substances. Bond all post-tensioned prestressing steel to
the concrete by filling the void space between the duct and tendon with
grout according to the *PTI Guide Specification for Grouting of
Post-Tensioned Structures.*

Perform all grouting operations using staff with grouting experience on
projects of a similar type and magnitude. Perform grouting operations
under the immediate supervision of an individual skilled in various
aspects of grouting and who is certified by the American Segmental
Bridge Institute (ASBI) Grouting Certification program. Furnish the name
of the grouting operations supervisor and proof of their ASBI
certification and grouting experience to the CO before beginning
grouting operations.

Make available on-site, before beginning grouting operations, all the
required testing equipment for checking grout workability (flow-cone),
temperatures, and other specified tests.

Use grouting equipment capable of continuous operation with little
variation of pressure, which also includes a system for recirculating
the grout while actual grouting is not in progress. Use grouting
equipment capable of maintaining a pressure on completely grouted ducts
and fitted with a valve that can be locked off without loss of pressure
in the duct.

Provide written certification that all ingredients used in the grout
meet the ASTM requirements contained in the *PTI Guide Specification for
Grouting of Post-Tensioned Structures.* This includes, but is not
limited to, the following:

• Cement mill test reports;

• Mineral additives test reports;

• Chemical admixtures reports; and

• Test reports for any other ingredients used in the grout.

For prepackaged grouts, provide the manufacturer's current certified
mill test reports for the product.

Do not use compressed air to aid in the pumping of grout.

Provide grout pumps of a positive displacement type, capable of
providing a continuous flow of grout, and capable of maintaining an
outlet pressure of at least 150 pounds per square inch and with a
pressure gauge having a full-scale reading of not more than 300 pounds
per square inch.

Determine the flowability of the grout according to ASTM C 939. The
efflux time of a grout sample immediately after mixing shall be between
11 and 30 seconds. Do not begin grouting until this test is passed. When
hot weather conditions may cause quick setting of the grout, cool the
grout by approved methods, as necessary, to prevent blockages during
pumping operations. When freezing weather conditions are possible during
and following placement of grout, protect the grout from damage by
freezing according to the *PTI Guide Specification for Grouting of
Post-Tensioned Structures*.

Provide a supply of potable water and standby flushing equipment capable
of developing a pumping pressure of 250 pounds per square inch and of
sufficient capacity to flush out any partially-grouted ducts.

Clean all ducts of material that would impair bonding of the grout or
interfere with grouting procedures. Blow out each duct with compressed,
oil-free air. Check all inlets and outlets for their capacity to accept
injection of grout by blowing compressed, oil-free air through the
system and proving each inlet and outlet in turn.

Pass all grout through a screen with 1/8 inch maximum clear openings
before entering the grout pump. Open all grout vents prior to the
commencement of grouting. Completely fill the duct by injecting grout
from the lowest end of the tendon in an uphill direction. Pump grout
continuously through the duct and waste at the outlet until no visible
slugs of water or air are ejected, and the efflux time of ejected grout
is between 11 and 30 seconds. Maintain a continuous, one-way flow of
grout within a grouting stage.

Close all outlets in a similar manner one after the other in the
direction of the flow. For outlets placed a short distance downstream
from a high point, close that outlet before its associated high point
outlet. Increase the grouting pressure at the injection end to at least
100 pounds per square inch and hold for at least 10 seconds. Do not
remove or open valves and caps until the grout has set.

Abrasive blast clean the concrete surface of recessed anchorage
assemblies. Fill anchor recesses with concrete conforming to the
requirements for the structure and finish flush.

Remove ends of vents 1 inch below the roadway surface after grouting has
been completed. Permanently seal all recess areas.

Do not release the falsework under the bottom slab supporting the
superstructure until at least 48 hours after grouting of the
post-tension prestressing steel or until the grout strength is obtained.

Table 553-1

Prestressed Concrete Member Tolerances

+---------------------------------------+------------------------------+
| **Description**                       | **Tolerance**                |
+---------------------------------------+------------------------------+
| **Precast Girders With Cast-In-Place  |                              |
| Deck^(1)^**                           |                              |
+---------------------------------------+------------------------------+
| Length                                | ±1/4 inch/25 feet, ±1 inch   |
|                                       | max.                         |
+---------------------------------------+------------------------------+
| Width (overall)                       | +3/8 inch, -1/4 inch         |
+---------------------------------------+------------------------------+
| Depth (overall)                       | +1/2 inch, -1/4 inch         |
+---------------------------------------+------------------------------+
| Depth (flanges)                       | -1/4 inch                    |
+---------------------------------------+------------------------------+
| Width (web)                           | +3/8 inch, -1/4 inch         |
+---------------------------------------+------------------------------+
| Sweep ^(2)^                           | 1/8 inch/10 feet             |
+---------------------------------------+------------------------------+
| Variation from end squareness or skew | ±3/16 inch/foot, ±1inch max. |
+---------------------------------------+------------------------------+
| Camber variation from design camber   | ±1/8 inch/10 feet            |
|                                       |                              |
|                                       | ±1/2 inch, max. ≤ 80 foot    |
|                                       | length                       |
|                                       |                              |
|                                       | ±1 inch, max. \> 80 foot     |
|                                       | length                       |
+---------------------------------------+------------------------------+
| Position of strands:                  | ±1/4 inch                    |
|                                       |                              |
| > Individual                          | ±1/2 inch                    |
| >                                     |                              |
| > Bundled                             | ±20 inches                   |
|                                       |                              |
| Position from design location of      |                              |
| deflection points for deflected       |                              |
| strands                               |                              |
+---------------------------------------+------------------------------+
| Position of plates other than bearing | ±1 inch                      |
| plates                                |                              |
+---------------------------------------+------------------------------+
| Position of bearing plates            | ±5/8 inch                    |
+---------------------------------------+------------------------------+
| Tipping and flushness of plates       | ±1/4 inch                    |
+---------------------------------------+------------------------------+
| Tipping and flushness of bearing      | ±1/8 inch                    |
| plates                                |                              |
+---------------------------------------+------------------------------+
| Position of inserts for structural    | ±1/2 inch                    |
| connections                           |                              |
+---------------------------------------+------------------------------+
| Position of handling devices:         | ±6 inches                    |
|                                       |                              |
| > Parallel to length                  | ±1 inch                      |
| >                                     |                              |
| > Transverse to length                |                              |
+---------------------------------------+------------------------------+
| Position of stirrups:                 | ±2 inches                    |
|                                       |                              |
| > Longitudinal spacing                | ±3/4 inch                    |
| >                                     |                              |
| > Projection above top                |                              |
+---------------------------------------+------------------------------+
| Local smoothness ^(3)^                | ±1/4 inch in 10 feet any     |
|                                       | surface                      |
+---------------------------------------+------------------------------+

\(1\) AASHTO I Beams and Bulb Tee Girders.

\(2\) Variation from straight line parallel to centerline of member.

\(3\) Does not apply to top surface left rough to receive a topping or
to visually concealed surfaces.

Table 553-1 (continued)

Prestressed Concrete Member Tolerances

+----------------------------------------+-----------------------------+
| **Description**                        | **Tolerance**               |
+----------------------------------------+-----------------------------+
| **Precast Girders Used In Multi-Beam   |                             |
| Decks ^(4)^**                          |                             |
+----------------------------------------+-----------------------------+
| Length                                 | ±3/4 inch                   |
+----------------------------------------+-----------------------------+
| Width (overall)                        | ±1/4 inch                   |
+----------------------------------------+-----------------------------+
| Depth (overall)                        | ±1/4 inch                   |
+----------------------------------------+-----------------------------+
| Depth (top flange)                     | ±1/2 inch                   |
+----------------------------------------+-----------------------------+
| Depth (bottom flange)                  | +1/2 inch, -1/8 inch        |
+----------------------------------------+-----------------------------+
| Width (web)                            | ±3/8 inch                   |
+----------------------------------------+-----------------------------+
| Sweep ^(5)^                            | ±1/4 inch                   |
|                                        |                             |
| > Up to 12 m member length             | ±3/8 inch                   |
| >                                      |                             |
| > 12 to 18 m member length             | ±1/2 inch                   |
| >                                      |                             |
| > Greater than 18 m member length      |                             |
+----------------------------------------+-----------------------------+
| Variation from end squareness or skew  | ±1/8 inch/foot              |
|                                        |                             |
| > Horizontal                           | ±1/2 inch max.              |
| >                                      |                             |
| > Vertical                             | ±1/2 inch                   |
+----------------------------------------+-----------------------------+
| Camber variation from design camber    | ±1/8 inch/10 feet           |
|                                        |                             |
|                                        | ±1/2 inch max.              |
+----------------------------------------+-----------------------------+
| Differential camber between adjacent   | 1/4 inch /10 feet           |
|                                        |                             |
| members of the same design             | 3/4 inch max.               |
+----------------------------------------+-----------------------------+
| Position of Strands:                   | ±1/4 inch                   |
|                                        |                             |
| > Individual                           | ±1/4 inch                   |
| >                                      |                             |
| > Bundled                              | ±20 inches                  |
|                                        |                             |
| Position from design location of       |                             |
|                                        |                             |
| deflection points for deflected        |                             |
| strands                                |                             |
+----------------------------------------+-----------------------------+
| Position of plates other than bearing  | ±1 inch                     |
| plates                                 |                             |
+----------------------------------------+-----------------------------+
| Tipping and flushness of plates        | ±1/4 inch                   |
+----------------------------------------+-----------------------------+
| Position of inserts for structural     | ±1/2 inch                   |
| connections                            |                             |
+----------------------------------------+-----------------------------+
| Position of handling devices:          | ±6 inches                   |
|                                        |                             |
| > Parallel to length                   | ±1 inch                     |
| >                                      |                             |
| > Transverse to length                 |                             |
+----------------------------------------+-----------------------------+

\(4\) Box beams, slabs, decked bulb tee, and multi-stem girders.

\(5\) Variation from straight line parallel to centerline of member.

Table 553-1 (continued)

Prestressed Concrete Member Tolerances

+--------------------------------------+-------------------------------+
| **Description**                      | **Tolerance**                 |
+--------------------------------------+-------------------------------+
| **Precast Girders Used In Multi-Beam |                               |
| Decks**                              |                               |
+--------------------------------------+-------------------------------+
| Position of stirrups:                | ±1 inch                       |
|                                      |                               |
| > Longitudinal spacing               | +1/4 inch, -3/4 inch          |
| >                                    |                               |
| > Projection above top               |                               |
+--------------------------------------+-------------------------------+
| Tipping of beam seat bearing area    | ±1/8 inch                     |
+--------------------------------------+-------------------------------+
| Position of dowel tubes              | ±5/8 inch                     |
+--------------------------------------+-------------------------------+
| Position of tie rod tubes:           | ±1/2 inch                     |
|                                      |                               |
| > Parallel to length                 | ±3/8 inch                     |
| >                                    |                               |
| > Vertical                           |                               |
+--------------------------------------+-------------------------------+
| Position of slab void:               | ±1/2 inch                     |
|                                      |                               |
| > End of void to center of tie hole  | ±1 inch                       |
| >                                    |                               |
| > Adjacent to end block              |                               |
+--------------------------------------+-------------------------------+
| Local smoothness ^(6)^               | ±1/4 inch in 10 feet any      |
|                                      | surface                       |
+--------------------------------------+-------------------------------+
| **Post-Tension Members**             |                               |
+--------------------------------------+-------------------------------+
| Position of post tensioning ducts    | ±1/4 inch                     |
+--------------------------------------+-------------------------------+
| Position of tendon anchorage bearing | ±1/4 inch                     |
| plates                               |                               |
+--------------------------------------+-------------------------------+

\(6\) Does not apply to top surface left rough to receive a topping or
to visually-concealed surfaces.

**553.10 Painting Steel.** Use a wire brush or abrasive blast to remove
all dirt and residue not firmly bonded to the metal or concrete
surfaces. Clean and paint the exposed ends of the prestress steel,
post-tension anchor head assemblies, and a 1-inch strip of adjoining
concrete.

Mix zinc-rich paint conforming to FSS TT-P-641. Work the paint into all
voids in the prestressing tendons. Apply one thick coat to surfaces that
will be covered with concrete. Apply 2 coats to surfaces not covered
with concrete.

**553.11 Acceptance.** See Tables 552-9 and 553-2 for sampling and
testing requirements.

Prestressing steel, reinforcing steel, anchor devices, elastomeric
bearings, and material for concrete and grout will be evaluated under
Subsection 106.03. Furnish production certifications for hydraulic
cement, prestressing steel, and reinforcing steel.

Grouting will be evaluated under Subsections 106.02 and 106.04. Sampling
and testing requirements will be according to the *PTI Guide
Specification for Grouting of Post‑Tensioned Structures.*

Concrete for precast, prestressed concrete members will be evaluated
under Subsections 106.02, 106.03, and 106.04.

Concrete for post-tensioned, cast-in-place concrete members will be
evaluated under Section 552.

Construction of precast, prestressed concrete members and
post-tensioned, cast-in-place concrete members will be evaluated under
Subsections 106.02 and 106.04.

Reinforcing steel will be evaluated under Section 554.

Falsework and forms will be evaluated under Section 562.

Measurement

**553.12** Measure the Section 553 items listed in the bid schedule
according to Subsection 109.02 and the following as applicable.

Do not measure reinforcing steel or concrete for precast, prestressed
concrete structural members.

Measure the concrete for post-tensioned, cast-in-place concrete
structures under Section 552. Measure the reinforcing steel for
post-tensioned, cast-in-place concrete structures under Section 554.

Measure prestressed piling under Section 551.

Payment

**553.13** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 553 pay items listed in the bid
schedule. Payment will be full compensation for the work prescribed in
this Section. See Subsection 109.05.

+------------+----------+--------------+--------------+------+-------+
| Table      | **R      | Upon         | Upon         | \    | \(2\) |
| 553-2      | eporting | completing   | completing   | (1\) | In    |
|            | Time**   |              |              | Sa   | add   |
| Sampling   |          | tests        | tests        | mple | ition |
| and        |          |              |              | a    | to    |
| Testing    |          |              |              | ccor | the   |
| Re         |          |              |              | ding | test  |
| quirements |          |              |              | to   | cyli  |
|            |          |              |              | AA   | nders |
|            |          |              |              | SHTO | req   |
|            |          |              |              | T    | uired |
|            |          |              |              | 141  | to    |
|            |          |              |              | ex   | dete  |
|            |          |              |              | cept | rmine |
|            |          |              |              | c    | 2     |
|            |          |              |              | ompo | 8-day |
|            |          |              |              | site | stre  |
|            |          |              |              | sam  | ngth, |
|            |          |              |              | ples | cast  |
|            |          |              |              | are  | 2     |
|            |          |              |              | not  | re    |
|            |          |              |              | r    | lease |
|            |          |              |              | equi | cyli  |
|            |          |              |              | red. | nders |
|            |          |              |              |      | for   |
|            |          |              |              |      | each  |
|            |          |              |              |      | con   |
|            |          |              |              |      | crete |
|            |          |              |              |      | me    |
|            |          |              |              |      | mber. |
|            |          |              |              |      | Cure  |
|            |          |              |              |      | the   |
|            |          |              |              |      | r     |
|            |          |              |              |      | eleas |
|            |          |              |              |      | e-str |
|            |          |              |              |      | ength |
|            |          |              |              |      | cyli  |
|            |          |              |              |      | nders |
|            |          |              |              |      | with  |
|            |          |              |              |      | the   |
|            |          |              |              |      | con   |
|            |          |              |              |      | crete |
|            |          |              |              |      | m     |
|            |          |              |              |      | ember |
|            |          |              |              |      | that  |
|            |          |              |              |      | they  |
|            |          |              |              |      | repre |
|            |          |              |              |      | sent. |
+------------+----------+--------------+--------------+------+-------+
|            | *        | Yes, when    | ---          |      |       |
|            | *Split** | requested    |              |      |       |
|            |          |              |              |      |       |
|            | **       |              |              |      |       |
|            | Sample** |              |              |      |       |
+------------+----------+--------------+--------------+------+-------+
|            | **Sa     | Discharge    | Each source  |      |       |
|            | mpling** | stream at    |              |      |       |
|            |          | point of     |              |      |       |
|            | *        |              |              |      |       |
|            | *Point** | placing^(1)^ |              |      |       |
+------------+----------+--------------+--------------+------+-------+
|            | **Sa     | 1 per 30 yd³ | Each mixture |      |       |
|            | mpling** | ^(2)^        |              |      |       |
|            |          |              |              |      |       |
|            | **Fre    |              |              |      |       |
|            | quency** |              |              |      |       |
+------------+----------+--------------+--------------+------+-------+
|            | **Test   | AASHTO T 23  | PTI Guide    |      |       |
|            | Methods  | &            | S            |      |       |
|            | or       |              | pecification |      |       |
|            | Specific | T 22         | for Grouting |      |       |
|            | ations** |              | of           |      |       |
|            |          |              | Po           |      |       |
|            |          |              | st-Tensioned |      |       |
|            |          |              | Structures   |      |       |
+------------+----------+--------------+--------------+------+-------+
|            | **Ca     | ---          | ---          |      |       |
|            | tegory** |              |              |      |       |
+------------+----------+--------------+--------------+------+-------+
|            | **       | Compressive  | ---          |      |       |
|            | Characte | strength     |              |      |       |
|            | ristic** |              |              |      |       |
+------------+----------+--------------+--------------+------+-------+
|            | **Type   | Measured and | Measured and |      |       |
|            | of       | tested       | tested       |      |       |
|            | Ac       |              |              |      |       |
|            | ceptance | for          | for          |      |       |
|            | (Subse   | conformance  | conformance  |      |       |
|            | ction)** | (106.04)     | (106.04)     |      |       |
+------------+----------+--------------+--------------+------+-------+
|            | **       | Prestressed  | Grout        |      |       |
|            | Material |              |              |      |       |
|            | or       | concrete     |              |      |       |
|            | P        |              |              |      |       |
|            | roduct** |              |              |      |       |
+------------+----------+--------------+--------------+------+-------+

## Section 554. --- REINFORCING STEEL

Description

**554.01** This work consists of furnishing and placing reinforcing
steel.

Material

**554.02** Conform to the following Subsection:

Reinforcing steel 709.01

Construction Requirements

**554.03 Order Lists.** On reinforcing steel order lists, use the same
respective bar marks for labeling as shown on the plans. Submit all
order lists and bending diagrams for acceptance. Acceptance does not
relieve the Contractor of responsibility for the accuracy of the lists
and diagrams. Do not order material until the lists and diagrams are
accepted.

Do not fabricate vertical reinforcement in columns, walls, piers, and
shafts until footing elevations are established in the field.

**554.04 Identification.** Ship bar reinforcement in standard bundles,
tagged and marked according to CRSI *Manual of Standard Practice.*

**554.05 Bending.** Fabricate reinforcing bars according to ACI SP 66.
Cold bend all reinforcing bars that require bending. Limit the overall
height or drop bending tolerance of deck truss bars to plus 0 inch or
minus 1/4 inch. Do not bend bars partially embedded in concrete except
as shown on the plans or otherwise permitted.

When the dimensions of hooks or the diameter of bends are not shown on
the plans, provide standard hooks conforming to ACI SP 66.

**554.06 Protection of Material.** Store reinforcing steel above the
ground on platforms, skids, or other supports. Protect from physical
damage, rust, and other surface deterioration.

Use reinforcing steel only when the surface is clean and the minimum
dimensions, cross-sectional area, and tensile properties conform to the
physical requirements for the size and grade of steel specified.

Do not use reinforcing steel that is cracked, laminated, or is covered
with dirt, rust, loose scale, paint, grease, oil, or other deleterious
material.

**554.07 Epoxy Coated Reinforcing Steel.** Support coated bars on padded
contact areas. Pad all bundled bands. Lift with a strong back, multiple
supports, or a platform bridge. Prevent bar-to-bar abrasion. Do not drop
or drag bundles.

Before placement, inspect coated bars for damage to the coating. Patch
all defects in the coating that are discernable to the unaided eye with
a prequalified patching/repair material according to AASHTO M 284. Clean
areas to be patched by removing all surface contaminants and damaged
coating. Roughen the area to be patched before applying the patching
material. Where rust is present, remove the rust by blast cleaning or
power tool cleaning immediately before applying the patching material.

Promptly treat the bar according to the resin manufacturer\'s
recommendations and before detrimental oxidation occurs. Overlap the
patching material onto the original coating for 2 inches or as
recommended by the manufacturer. Provide a minimum 8 mil dry film
thickness on the patched areas.

Take necessary steps to minimize damage to the epoxy coating of
installed bars. Clean and patch any damage to the coating noted after
installation as described above.

Field repairs will not be allowed on bars that have severely-damaged
coatings. Replace bars with severely-damaged coatings. A
severely-damaged coating is defined as a coating with a total damaged
area in any 1-foot length of bar that exceeds 5 percent of the surface
area of that portion of the bar. Coat mechanical splices after splice
installation according to AASHTO M 284 for patching damaged epoxy
coatings.

**554.08 Placing and Fastening.** Support the bars on precast concrete
blocks or metal supports according to the CRSI *Manual of Standard
Practice.* Attach concrete block supports to the supported bar with wire
cast in the center of each block. Use class 1 (plastic protected) or
class 2, type B (stainless steel protected) metal supports in contact
with exposed concrete surfaces. Use stainless steel conforming to ASTM A
493, type 430.

Coat chairs, tie wires, and other devices used to support, position, or
fasten epoxy-coated reinforcement with a dielectric material. Do not use
plastic supports.

Space slab bar supports no more than 4 feet apart transversely or
longitudinally. Do not use bar supports either directly or indirectly to
support runways for concrete buggies or other similar construction
loads.

Space parallel bars within 1½ inches of the required location. Do not
cumulate spacing variations. The average of any two adjacent spaces
shall not exceed the required spacing.

Provide 2 inches clear cover for all reinforcement except as otherwise
shown on the plans.

Place reinforcing steel in deck slabs within 1/4 inch of the vertical
plan location. Tie bridge deck reinforcing bars together at all
intersections except where spacing is less than 12 inches in both
directions, in which case alternate intersections may be tied. Check the
clear cover over deck reinforcing steel using a template before placing
deck concrete. Replace damaged supports.

Tie bundle bars together at intervals not exceeding 6 feet. Do not
bundle bars unless the location and splice details are specified.

Do not place concrete in any member until the placement of the
reinforcement is approved.

**554.09 Splices.** Splicing, except as shown on the plans, is not
permitted without approval. Provide lap lengths shown on the plans.
Splice reinforcing bars only where shown on the plans or accepted
drawings. Do not place slab bar mechanical splices adjacent to each
other.

Make lapped splices by placing the reinforcing bars in contact and
wiring them together so as to maintain the alignment and position of the
bars.

If welding of reinforcing steel is permitted by the contract, the welds
shall conform to AWS D 1.4. Do not weld reinforcing steel if the
chemical composition of the steel exceeds the percentages in Table
554-1.

Table 554-1

Reinforcing Steel Components

  ------------------------------------------------- ---------------------
  **Chemical Composition**                          **Percent**

  Carbon (C)                                        0.30

  Manganese (MA)                                    1.50

  Carbon Equivalent (C.E.)                          0.55
  ------------------------------------------------- ---------------------

Use welders that are currently certified. When required in the contract,
test each weld using magnetic particle, radiography, or other
nondestructive inspection techniques.

Mechanical couplers may be used in lieu of welding if approved. Use
couplers with a strength that is at least 125 percent of the required
yield strength of the reinforcing steel.

If welded wire fabric is shipped in rolls, straighten into flat sheets
before placing. Splice sheets of mesh or bar mat reinforcement by
overlapping not less than 1-mesh width plus 2 inches. Securely fasten at
the ends and edges.

**554.10 Acceptance.** Reinforcing steel and epoxy coating material will
be evaluated under Subsections 106.02 and 106.03. Furnish a production
certification with each shipment of reinforcing steel.

Placement of reinforcing steel will be evaluated under Subsections
106.02 and 106.04.

Measurement

**554.11** Measure the Section 554 items listed in the bid schedule
according to Subsection 109.02 and the following as applicable.

Measure reinforcing steel excluding laps added for the Contractor\'s
convenience. Do not measure couplers or mechanical splicers. Do not
measure chairs, mortar blocks or other items used to support reinforcing
steel and supports.

Payment

**554.12** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 554 pay items listed in the bid
schedule. Payment will be full compensation for the work prescribed in
this Section. See Subsection 109.05.

## Section 555. --- STEEL STRUCTURES

Description

**555.01** This work consists of constructing steel structures and the
steel structure portions of composite structures. It includes
furnishing, fabricating, and erecting structural steels and incidental
metal construction.

Material

**555.02** Conform to the following Sections and Subsections:

Bearing devices 564

Bolts and nuts 717.01(d)

Castings 717.04

Elastomeric compression joint seals 717.16

Falsework 562

Galvanized coatings 717.07

High-strength bolts, nuts, and washers 717.01(e)

Painting 563

Pins and rollers 717.03

Sheet lead 717.08

Steel forgings 717.02

Steel grid floors 717.09

Steel pipe 717.06

Structural steels 717.01

Welded stud shear connectors 717.05

Construction Requirements

**555.03 General.** Fabricate the structural steel in a fabricating
plant that is certified under the AISC *Quality Certification Program*.
Fabricate fracture critical elements according to the AASHTO *Guide
Specifications for Fracture Critical Non‑Redundant Steel Bridge
Members.*

Perform welding and weld qualification tests according to the provisions
of ANSI/AASHTO/AWS Bridge Welding Code D1.5.

**555.04 Notice of Beginning of Work.** Give written notice 21 days
before the beginning of work at the shop. Do not manufacture any
material or perform any work in the shop before notification.

**555.05 Inspection.** Structural steel may be inspected at the
fabrication site according to Subsection 106.06.

Ultrasonically inspect all girder flanges before fabrication according
to ASTM A 578M except as follows:

**(a)** Inspect after the flanges are stripped from the master plate.

**(b)** Sections 6 and 7 acceptance standards do not apply. Use
supplementary requirement S2.1 for acceptance standards.

**(c)** Flanges may be inspected in the plant or warehouse where the
flanges are stripped.

Furnish a copy of all mill orders and certified mill test reports. Show
on the mill test reports the chemical analyses and physical test results
for each heat of steel used in the work.

If approved, furnish production certifications in lieu of mill test
reports for material that normally is not supplied with mill test
reports and for items such as fills, minor gusset plates, and similar
material when quantities are small and the material is taken from stock.

Include in the certified mill test reports for steels with specified
impact values, in addition to other test results, the results of Charpy
V‑notch impact tests. When fine-grain practice is specified, confirm on
the test report that the material was so produced. Furnish copies of
mill orders at the time orders are placed with the manufacturer. Furnish
certified mill test reports and production certifications before the
start of fabrication using material covered by these reports. Furnish,
from the manufacturer, a production certification according to
Subsection 106.03.

**555.06 Drawings (Shop Drawings, Erection Drawings, and Transportation
Drawings).** Prepare and submit drawings according to Subsection 104.03.
Acceptance of the drawings covers the requirements for strength and
detail only. No responsibility is assumed for errors in dimensions.

**(a) Shop drawings.** Show full, detailed dimensions and sizes of
component parts of the structure and details of all miscellaneous parts
(such as pins, nuts, bolts, drains, weld symbols, etc.) on shop drawings
for steel structures.

Where specific orientation of plates is required, show the direction of
rolling of plates. Cut flanges and webs of plate girders from plates so
the long dimension of the girder parallels the rolling direction.

Identify on the shop drawings the type and grade of each piece that is
to be made of steel other than AASHTO M 270, grade 36 steel.

Show on the shop drawings assembly marks that are cross-referenced to
the original pieces of mill steel and their certified mill test reports.

The location of all shop-welded splices shown on the shop drawings are
subject to approval. Locate all shop-welded splices to avoid points of
maximum tensile or fatigue stress. Locate splices in webs at least 12
inches from shop splices, butt joints in flanges, or stiffeners.
Additional nondestructive tests may be required on shop-welded splices.

**(b) Erection drawings.** Submit drawings fully illustrating the
proposed method of erection. Show details of all falsework bents,
bracing, guys, dead‑men, lifting devices, and attachments to the bridge
members. Show the sequence of erection, location of cranes and barges,
crane capacities, location of lifting points, and masses of bridge
members. Show complete details for all anticipated phases and conditions
of erection. Calculations may be required to demonstrate that allowable
stresses are not exceeded and that member capacities and final geometry
are correct. See Section 562 for additional requirements.

**(c) Camber diagram.** Furnish a camber diagram that shows the camber
at each panel point of trusses or arch ribs and at the location of field
splices and fractions of span length (quarter points minimum) of
continuous beams and girders or rigid frames. On the camber diagram,
show calculated cambers to be used in preassembly of the structure as
required in Subsection 555.15.

**(d) Transportation drawings.** Show all support points, tie-downs,
temporary stiffening trusses or beams, and any other details needed to
support and brace the member. Provide calculation sheets showing dead
load plus impact stresses induced by the loading and transportation
procedure. Use impact stresses of at least 200 percent of the dead load
stress. Use a total load, including impact, of not less than 300 percent
of the dead load.

If required, furnish transportation drawings for acceptance.

Ship and store all members, both straight and curved, with their webs
vertical.

**555.07 Storage of Material.** Store structural material above the
ground on platforms, skids, or other supports. Keep material free from
dirt, grease, and other foreign matter, and provide appropriate
protection from corrosion.

**555.08 Fabrication.**

**(a) Identification of steels.** Use a system of assembly‑marking of
individual pieces and cutting instructions to the shop (generally by
cross referencing of the assembly‑marks shown on the shop drawings with
the corresponding item covered on the mill purchase order) that
maintains the identity of the original piece.

Material may be furnished from stock, which can be identified, by heat
number and mill test report.

During fabrication, up to the point of assembling members, show clearly
and legibly the specification of each piece of steel (other than grade
36 steel) by writing the material specification on the piece or using
the identification color code shown in Table 555-1.

Table 555-1

Identification Color Codes

  ------------------------- ---------------------------------------------
  **Grade**                 **Color**

  50                        Green and Yellow

  50W                       Blue and Yellow

  70W                       Blue and Orange

  100                       Red

  100W                      Red and Orange
  ------------------------- ---------------------------------------------

For other steels (except grade 36 steel) not shown in Table 555-1 or
included in AASHTO M 160, provide information on color code used.

Mark for grade by steel die stamping, or by a substantial
firmly-attached tag, pieces of steel (other than grade 250 steel) that,
before assembling into members, will be subject to fabricating
operations (such as blast cleaning, galvanizing, heating for forming, or
painting) that might obliterate paint color code marking. Where the
steel stamping method is used, place the impressions on the thicker
tension-joint member in transition joints.

The maximum allowed depth of the impression is 0.010 inches. Use a tool
that makes character sizes with corresponding face radii as shown in
Table 555-2. Avoid impressions near edges of tensile-stressed plate
members.

Table 555-2

Size of Steel Die Stamp Markings

  ------------------------------ ----------------------------------------
  **Character Size**             **Minimum Face Radii**

  1/8 inch                       0.007 inches

  3/16 inch                      0.003 inches

  1/4 inch                       0.010 inches
  ------------------------------ ----------------------------------------

Use low-stress type steel die stamps. Do not use die stamps on
fracture-critical members.

If requested, furnish an affidavit certifying that throughout the
fabrication operation, the identification of steel has been maintained.

Heat curving of steel girders is not allowed.

Do not drill, cut, or weld portions of structural members unless shown
in the plans or approved in writing.

**(b) Plates.**

**(1) Direction of rolling.** Unless otherwise shown on the drawings,
cut and fabricate steel plates for main members and splice plates for
flanges and main tension members, not secondary members, so that the
primary direction of rolling is parallel to the direction of the
principal tensile and compressive stresses.

**(2) Plate cut edges.**

*(a) Edge planing.* Remove sheared edges on plates thicker than 5/8 inch
to a depth of 1/4 inch beyond the original sheared edge or beyond any
re-entrant cut produced by shearing. Fillet re-entrant cuts before
cutting.

*(1) Oxygen cutting.* Oxygen cut structural steel according to
ANSI/AASHTO/AWS Bridge Welding Code D1.5.

*(2) Visual inspection and repair of plate cut edges.* Visually inspect
and repair plate cut edges. The cut edges shall conform to
ANSI/AASHTO/AWS Bridge Welding Code D1.5.

*(b) Flange plates.* Furnish flange plates with either oxygen-cut edges
that have the corners chamfered at least 1/16 inch by grinding, or
furnish Universal mill plates unless oxygen-cut edges are required.

*(c) Web plates.* Oxygen cut to the prescribed camber web plates of
built-up beams and girders, box girders, and box arches. Cut sufficient
extra camber into the webs to provide for all camber losses due to
welding, cutting, etc.

*(d) Truss members.* Prepare, by oxygen cutting, all longitudinal edges
of all plates in welded sections of truss web and chord members.
Chamfer, by grinding the edges of the corners of plates not joined by
welding, at least 1/16 inch.

*(e) Stiffeners and connection plates.* Stiffeners and connection plates
welded transverse to girder webs and flanges may be furnished with
sheared edges provided the plate thickness does not exceed 3/4 inch.
Universal mill plate may be used provided its thickness does not exceed
1 inch. Furnish other stiffeners and connection plates with oxygen-cut
edges.

*(f) Lateral gusset plates.* Oxygen cut, parallel to lines of stress,
gusset plates and other connections welded parallel to lines of stress
in tension members where the plate thickness exceeds 3/8 inch. Bolted
lateral gusset plates may be furnished with sheared edges provided the
thickness is less than or equal to 3/4 inch.

*(g) Splice plates and gusset plates.* Furnish girder and stringer
splice plates and truss gusset plates with oxygen-cut edges.

*(h) Bent plates.* Furnish unwelded, load‑carrying, rolled‑steel plates
to be bent as follows.

Take material from the stock plates such that the bend line is at right
angles to the direction of rolling, except that cold‑bent ribs for
orthotopic‑deck bridges may be bent with bend lines in the direction of
rolling.

Before bending, round the corners of the plates to a radius of 1/16 inch
throughout the portion of the plate where the bending occurs.

*(1) Cold bending.* Cold bend so that no cracking of the plate occurs.
Use the minimum bend radii shown in Table 555-3 measured to the concave
face of the metal.

Allow for springback of grades 100 and 100W steels equal to about three
times that for grade 36 steel. Use a lower die span of at least 16 times
the plate thickness for break press forming.

*(2) Hot bending.* If a radius shorter than the minimum specified for
cold bending is essential, hot bend the plates at a temperature not
greater than 1,100 ºF, except for grades 100 and 100W. When grades 100
and 100W steel plates are heated to temperatures greater than 1,100 ºF,
requench and temper according to the producing mill\'s standard
practice.

Table 555-3

Minimum Bending Radii

+-----------------------------------+----------------------------------+
| **Plate Thickness - (t)**         | **Bending Radius ^(1)^**         |
|                                   |                                  |
| **(inches)**                      | **(inches)**                     |
+-----------------------------------+----------------------------------+
| ≤ 1/2                             | 2(t)                             |
+-----------------------------------+----------------------------------+
| Over 1/2 to 1                     | 2.5(t)                           |
+-----------------------------------+----------------------------------+
| Over 1 to 1½                      | 3(t)                             |
+-----------------------------------+----------------------------------+
| Over 1½ to 2½                     | 3.5(t)                           |
+-----------------------------------+----------------------------------+
| Over 2½ to 4                      | 4(t)                             |
+-----------------------------------+----------------------------------+

\(1\) Bend radii for all grades of structural steel.

**(c) Fit of stiffeners.** Fabricate (mill, grind, or weld as shown on
the plans or as specified) end bearing stiffeners for girders and
stiffeners intended as supports for concentrated loads to provide full
bearing on the flanges to which they transmit load or from which they
receive load. Fabricate intermediate stiffeners not intended to support
concentrated loads to provide a tight fit against the compression
flange.

**(d) Abutting joints.** Mill or saw cut abutting joints in compression
members of trusses and columns to give a square joint and uniform
bearing. The maximum allowed opening at other joints, not required to be
faced, is 3/8 inch.

**(e) Facing of bearing surfaces.** Finish bearing, base plates, and
other bearing surfaces that will come in contact with each other, or
with concrete, to the ANSI surface roughness defined in ANSI B46.1,
*Surface Roughness, Waviness and Lay, Part I,* as shown in Table 555-4.

Table 555-4

ANSI Surface Roughness Values

+-----------------------------------------------+----------------------+
| **Bearing Surface**                           | **Surface Roughness  |
|                                               | Value**              |
|                                               |                      |
|                                               | **(microinches)**    |
+-----------------------------------------------+----------------------+
| Steel slabs                                   | 2,000                |
+-----------------------------------------------+----------------------+
| Heavy plates in contact in shoes to be welded | 1,000                |
+-----------------------------------------------+----------------------+
| Milled ends of compression members, milled or | 500                  |
|                                               |                      |
| ground ends of stiffeners and fillers         |                      |
+-----------------------------------------------+----------------------+
| Bridge rollers and rockers                    | 250                  |
+-----------------------------------------------+----------------------+
| Pins and pin holes                            | 125                  |
+-----------------------------------------------+----------------------+
| Sliding bearings                              | 125                  |
+-----------------------------------------------+----------------------+

Machine sliding bearings that have a surface roughness greater than 75
microinches according to ANSI 60 so the lay of the cut is parallel to
the direction of movement.

Fabricate parts in bearing to provide a uniform even contact with
adjacent bearing surface when assembled. Limit maximum gap between
bearing surfaces to 0.04 inches. Base and sole plates that are plane and
true and have a surface roughness not exceeding the above tabulated
values need not be machined except machine sliding surfaces of base
plates.

Do not machine surfaces of fabricated members until all fabrication on
that particular assembly or subassembly is complete. Machine metal
components that are to be heat treated after heat treatment.

**(f) Straightening material.** If approved, straighten plates, angles,
other shapes, and built‑up members by methods that do not produce
fracture or other damage to the metal. Straighten distorted members by
mechanical means or, if approved, by carefully planned procedures and
supervised application of a limited amount of localized heat. Use
rigidly-controlled procedures and do not exceed the temperatures
specified in Table 555-5 when heat straightening grades 70W, 100, and
100W steel members.

Table 555-5

Heat Straightening Temperatures

  ----------------------------------------- -----------------------------
  **Material to be Straightened**           **Maximum Temperature**

  Grade 70W \> 6 inches from weld           1,075 ºF

  Grade 70W \< 6 inches from weld           900 ºF

  Grade 100 or 100W \> 6 inches from weld   1,125 ºF

  Grade 100 or 100W \< 6 inches from weld   950 ºF
  ----------------------------------------- -----------------------------

In all the other steels, do not exceed 1,200 ºF in the heated area.
Control the application by temperature-indicating crayons, liquids, or
bimetal thermometers.

Keep parts to be heat straightened and substantially free of external
forces and stress except stresses resulting from mechanical means used
in conjunction with the application of heat.

Evidence of fracture following straightening of a bend or buckle will be
cause for rejection of the damaged piece.

**555.09 Annealing and Stress Relieving.** Machine, finish bore, and
straighten annealed or normalized structural members after heat
treatment. Normalize and anneal (full annealing) according to ASTM A
919. Maintain uniform temperatures throughout the furnace during the
heating and cooling so that the temperature at no two points on the
member differs by more than 100 ºF at any one time.

Do not anneal or normalize members of grades 100/100W or 70W steels.
Stress relieve these grades only with approval.

Record each furnace charge, identify the pieces in the charge, and show
the temperatures and schedule actually used. Provide proper instruments,
including recording pyrometers, for determining at any time the
temperatures of members in the furnace. Make records of the treatment
operation available for approval. The maximum allowed holding
temperature for stress relieving grades 100/100W and grade 70W steels is
1,100 ºF and 1,050 ºF, respectively.

Stress relieve members (such as bridge shoes, pedestals, or other parts
that are built-up by welding sections of plate together) according to
Subsection 4.4 of ANSI/AASHTO/AWS Bridge Welding Code D1.5.

**555.10 Bolt Holes.** Punch or drill all bolt holes. Material forming
the parts of a member that is composed of not more than 5 thicknesses of
metal may be punched 1/16 inch larger than the nominal diameter of the
bolts where the thickness of the material is not greater than 3/4 inch
for structural steel, 5/8 inch for high-strength steel, or 1/2 inch for
quenched and tempered alloy steel unless subpunching and reaming is
required under (h), the preparation of field connections.

Where there are more than five thicknesses or where any of the main
material is thicker than 3/4 inch for structural steel, 5/8 inch for
high‑strength steel, or 1/2 inch for quenched and tempered alloy steel,
either subdrill and ream or drill all holes full size.

If required, either subpunch or subdrill (subdrill if thickness
limitation governs) 3/16 inch smaller and, after assembling, ream 1/16
inch larger or drill full size to 1/16 inch larger than the nominal
diameter of the bolts.

**(a) Punched holes.** Use a die diameter that is not more than 1/16
inch larger than the punch diameter. Ream holes that require enlarging
to admit bolts. Clean cut the holes without torn or ragged edges.

**(b) Reamed or drilled holes.** Ream or drill holes so they are
cylindrical and perpendicular to the member. Where practical, direct
reamers by mechanical means. Remove burrs on the outside surfaces. Ream
and drill with twist drills, twist reamers, or roto-broach cutters.
Assemble and securely hold together connecting parts that are being
reamed or drilled and match-mark before disassembling.

**(c) Accuracy of holes.** Holes not more than 1/32 inch larger in
diameter than the true decimal equivalent of the nominal diameter of the
drill or reamer are acceptable. The slightly conical hole resulting from
punching operations is acceptable. The width of slotted holes produced
by flame cutting or a combination of drilling or punching and flame
cutting shall be no more than 1/32 inch greater than the nominal width.
Grind flame cut surfaces smooth.

**(d) Accuracy of hole group before reaming.** Accurately punch full
size, subpunched, or subdrilled holes so that after assembling (before
any reaming is done) a cylindrical pin 1/8 inch smaller in diameter than
the nominal size of the punched hole may be entered perpendicular to the
face of the member, without drifting, in at least 75 percent of the
contiguous holes in the same plane. Punched pieces not meeting this
requirement will be rejected. Holes, through which a pin 3/16 inch
smaller in diameter than the nominal size of the punched hole cannot be
inserted, will be rejected.

**(e) Accuracy of hole group after reaming.** After reaming, the maximum
allowed offset of 85 percent of any contiguous group of holes through
adjacent thicknesses of metal is 1/32 inch.

Use steel templates having hardened steel bushings in holes accurately
dimensioned from the centerlines of the connection as inscribed on the
template. Use connection centerlines when locating templates from the
milled or scribed ends of members.

**(f) Numerically‑controlled drilled field connections.** In lieu of
drilling undersized holes and reaming while assembled, or drilling holes
full-size while assembled, drilling or punching bolt holes full-size in
unassembled pieces and connections, including templates for use with
matching undersized and reamed holes by means of suitable
numerically-controlled (N/C) drilling or punching equipment is allowed.

**(g) Holes for ribbed bolts, turned bolts, or other approved
bearing-type bolts.** Provide finished holes with a driving fit.

**(h) Preparation of field connections.** Subpunch or subdrill and ream
while assembled, or drill full size to a steel template, the holes in
field connections and field splices of main members of trusses, arches,
continuous beam spans, bents, towers (each face), plate girders, and
rigid frames.

Holes for field splices of rolled beam stringers continuous over floor
beams or cross frames may be drilled full-size unassembled to a steel
template. Holes for floor beams or cross frames may be drilled full size
unassembled to a steel template. Subpunch and ream while assembled, or
drill full size to a steel template, all holes for floor beam and
stringer field end connections.

When reaming or drilling full size field-connection holes through a
steel template, carefully locate and position the template, and firmly
bolt in place before drilling. Use exact duplicates of templates used
for reaming matching members or the opposite faces of a single member.
Accurately locate templates used for connections on like parts or
members so that the parts or members are duplicates and require no
match-marking.

For any connection, in lieu of subpunching and reaming or subdrilling
and reaming, holes drilled full size through all thicknesses or material
assembled in proper position may be used.

**555.11 Pins and Rollers.** Accurately fabricate pins and rollers that
are straight, smooth, and free from flaws. Forge and anneal pins and
rollers more than 9 inches in diameter. Pins and rollers 9 inches or
less in diameter may be either forged and annealed or cold‑finished
carbon steel shafting.

In pins larger than 9 inches in diameter, bore a hole not less than 2
inches in diameter full length along the pin axis after the forging has
been allowed to cool to a temperature below the critical range (under
suitable conditions to prevent damage by too rapid cooling and before
being annealed).

> **(a) Boring pin holes.** Bore pin holes true to the specified
> diameter, smooth and straight, at right angles with the axis of the
> member and parallel with each other. Produce the final surface using a
> finishing cut.

Produce a pin hole diameter that does not exceed that of the pin by more
than 1/50 inch for pins 5 inches or less in diameter or by 1/32 inch for
larger pins.

The maximum allowed variation of the outside-to-outside distance of end
holes in tension members and the inside-to-inside distance of end holes
in compression members is 1/32 inch from that specified. Bore pin holes
in built‑up members after the member has been assembled.

**(b) Threads for bolts and pins.** Provide threads on all bolts and
pins for structural steel construction that conform to the Unified
Standard Series UNC ANSI B1.1, class 2A for external threads and class
2B for internal threads except when pin ends have a diameter of 1⅜
inches or more, provide six threads per inch.

**555.12 Eyebars.** Pin holes may be flame cut at least 2 inches smaller
in diameter than the finished pin diameter. Securely fasten together (in
the order to be placed on the pin) all eyebars that are to be placed
side-by-side in the structure and bore at both ends while clamped. Pack
and match-mark eyebars for shipment and erection. Stamp with steel
stencils, so as to be visible when the bars are nested in place on the
structure, all identifying marks on the edge of one head of each member
after fabrication is completed. Use low-stress type steel die stamps.

Provide eyebars, straight and free from twists, with pin holes
accurately located on the centerline of the bar. Do not allow the
inclination of any bar to the plane of the truss to exceed 1/8 inch per
foot.

Simultaneously cut the edges of eyebars that lie between the transverse
centerline of their pin holes with two mechanically-operated torches
abreast of each other, guided by a substantial template to prevent
distortion of the plates.

**555.13 Assembly --- Bolting.** Clean surfaces of metal in contact
before assembling. Assemble parts of a member. Securely pin and firmly
draw together before drilling, reaming, or bolting is commenced. Take
assembled pieces apart, if necessary, for the removal of burrs and
shavings produced by the operation. Assemble members to be free from
twists, bends, and other deformation.

Drift during assembling only enough to bring the parts into position
without enlarging holes or distorting the metal.

**555.14 Welded Connections.** Fabricate surfaces and edges to be welded
smooth, uniform, clean, and free of defects that would adversely affect
the quality of the weld. Prepare edge according to ANSI/AASHTO/AWS
Bridge Welding Code D1.5.

**555.15 Preassembly of Field Connections.** Preassemble field
connections of main members of trusses, arches, continuous beams, plate
girders, bents, towers, and rigid frames before erection to verify the
geometry of the completed structure or unit and to verify or prepare
field splices. Present the method and details of preassembly for
approval.

Use methods and details of preassembly that are consistent with the
procedure shown on the approved erection camber diagrams. Assemble all
girders and beams in their cambered (no load) condition.

When members are assembled with their webs vertical, support them at
intervals of 20 feet, or two-tenths of the span length, whichever is
less. When the webs are horizontal, the above intervals of support may
be increased provided there is no noticeable deflection between points
of support.

Assemble trusses in full dead-load position unless the design of the
structure provides for the secondary stresses created by assembling the
truss in the fully cambered (no load) position. Support trusses during
assembly at each panel point. Preassemble at least 3 contiguous panels
that are accurately adjusted for line and camber. For successive
assemblies, include at least one section or panel of the previous
assembly (repositioned if necessary and adequately pinned to ensure
accurate alignment) plus 2 or more sections or panels added at the
advancing end. For structures longer than 150 feet, make each assembly
not less than 150 feet long regardless of the length of individual
continuous panels or sections. Assembly may start from any location in
the structure and proceed in one or both directions as long as preceding
requirements are satisfied.

**(a) Bolted connections.** Where applicable, assemble major components
with milled ends of compression members in full bearing and then ream
subsized holes to the specified size while the connections are
assembled.

**(b) Check assembly/numerically-controlled drilling.** When using
numerically- controlled drilling or punching, make a check assembly for
each major structural type of each project. Fabricate the check assembly
of at least 3 contiguous shop sections or, for a truss, all members in
at least 3 contiguous panels but not less than the number of panels
associated with 3 contiguous chord lengths (such as the length between
field splices). Base check assemblies on the proposed order of erection,
joints in bearings, special complex points, and similar considerations.
Shop assemblies other than the check assemblies are not required.

If the check assembly fails in some specific manner to demonstrate that
the required accuracy is being obtained, further check assemblies may be
required.

Receive approval of each assembly (including camber, alignment, accuracy
of holes, and fit of milled joints) before reaming is commenced or
before any N/C drilled check assembly is dismantled.

**(c) Field-welded connections.** Field-welded connections are
prohibited unless specifically shown on the drawings. Verify the fit of
members (including the proper space between abutting flanges) with the
segment preassembled.

**(d) Match marking.** Match mark connecting parts preassembled in the
shop to ensure proper fit in the field. Provide a diagram showing such
match-marks.

**555.16 Connections Using Unfinished, Turned, or Ribbed Bolts.** Use
unfinished, turned, or ribbed bolts, where specified, conforming to ASTM
A 307 for grade A bolts. Use bolts with single self-locking nuts or
double nuts. Use beveled washers where bearing faces have a slope of
more than 1:20 with respect to a plane normal to the bolt axis.

**(a) Turned bolts.** Furnish turned bolts with a body surface ANSI
roughness not exceeding 125 microinches. Furnish hex headed bolts and
nuts of the nominal size specified. Carefully ream holes for turned
bolts and furnish bolts to provide for a light driving fit. Keep bolt
threads entirely outside of the holes. Provide a washer under the nut.

**(b) Ribbed bolts.** Use approved form of ribbed body with continuous
longitudinal ribs. Provide a body diameter measured on a circle through
the points of the ribs 5/64 inch greater than the nominal diameter
specified for the bolts.

Furnish ribbed bolts with round heads conforming to ANSI B18.5. Furnish
hexagonal nuts that are either recessed or have a washer of suitable
thickness. Ribbed bolts shall have a driving fit when installed in
holes. Provide sufficiently hard ribs such that the ribs do not compress
or deform and allow the bolts to turn in the holes during tightening. If
the bolt twists before drawing tight, ream the hole and provide an
oversized replacement bolt.

**555.17 Connections Using High-Strength Bolts.** This subsection covers
the assembly of structural joints using AASHTO M 164 or M 253
high‑strength bolts, or equivalent fasteners, tightened to a high
tension.

**(a) Bolted parts.** Use steel material within the grip of the bolt
with no compressible material such as gaskets or insulation. Fabricate
bolted steel parts to fit solidly together after the bolts are
tightened. Limit the maximum slope of the surfaces of parts in contact
with the bolt head or nut to 1:20 with respect to a plane normal to the
bolt axis.

**(b) Surface conditions.** At the time of assembly, clean all joint
surfaces (including surfaces adjacent to the bolt head and nut) of dirt
or foreign material and scale except tight mill scale. Remove burrs that
would prevent solid seating of the connected parts in the snug-tight
condition.

Paint or other coatings are not permitted on the faying surfaces of
slip-critical connections. All connections are considered to be
slip-critical. Exclude paint (including any inadvertent overspray) from
areas closer than one-bolt diameter, but not less than 1 inch, from the
edge of any hole and all areas within the bolt pattern.

**(c) Installation.** Install fasteners of the same lot number together.
Protect fasteners from dirt and moisture. Take from protected storage
only as many fasteners as are anticipated to be installed and tightened
during a work shift. Return unused fasteners to protected storage at the
end of the shift. Do not clean lubricant from fasteners that is required
to be present in the as-delivered condition. Clean and relubricate,
before installation, fasteners for slip-critical connections that
accumulate rust or dirt.

Provide a tension measuring device (a Skidmore---Wilhelm calibrator or
other acceptable bolt tension indicating device) on all projects where
high-strength fasteners are being installed and tightened. Use the
tension measuring device to perform the rotational‑capacity test and to
confirm all of the following:

• Table 555-6 requirement for the complete fastener assembly

• Calibration of the wrenches, if applicable

• Understanding and proper use of the tightening method

Table 555-6

Minimum Fastener Tension^(1)^

+---------------------------+---------------------+--------------------+
| **Nominal Bolt Diameter** | **AASHTO M 164**    | **AASHTO M 253**   |
|                           |                     |                    |
| **(inches)**              | **(pounds)**        | **(pounds)**       |
+---------------------------+---------------------+--------------------+
| 1/2                       | 12,000              | 15,000             |
+---------------------------+---------------------+--------------------+
| 5/8                       | 19,000              | 24,000             |
+---------------------------+---------------------+--------------------+
| 3/4                       | 28,000              | 35,000             |
+---------------------------+---------------------+--------------------+
| 7/8                       | 39,000              | 49,000             |
+---------------------------+---------------------+--------------------+
| 1                         | 51,000              | 64,000             |
+---------------------------+---------------------+--------------------+
| 1⅛                        | 56,000              | 80,000             |
+---------------------------+---------------------+--------------------+
| 1¼                        | 71,000              | 102,000            |
+---------------------------+---------------------+--------------------+
| 1⅜                        | 85,000              | 121,000            |
+---------------------------+---------------------+--------------------+
| 1½                        | 103,000             | 148,000            |
+---------------------------+---------------------+--------------------+

\(1\) Equal to 70 percent of the specified minimum tensile strength of
bolts (as specified for tests of full size AASHTO M 164 and M 253 bolts
with UNC threads loaded in axial tension) rounded to the nearest 1,000
pounds.

For short grip bolts, direct tension indicators (DTI) with solid plates
may be used to perform this test. First check the DTI with a longer grip
bolt in the Skidmore‑Wilhelm calibrator. The frequency of confirmation
testing, number of tests to be performed, and test procedure shall
conform to (3) through (5) as applicable. Confirm the accuracy of the
tension measuring device by an approved testing agency at least
annually.

Install fasteners together with washers of size and quality specified,
located as required below, in properly aligned holes and tightened by
any of the methods described in (3) to (6) inclusive to at least the
minimum tension specified in Table 555-6 after all the fasteners are
tight.

If approved, tightening may be performed by turning the bolt while the
nut is prevented from rotating when it is impractical to turn the nut.
If impact wrenches are used, provide adequate capacity and sufficient
air to tighten each bolt in approximately 10 seconds.

Do not reuse AASHTO M 253 fasteners and galvanized AASHTO M 164
fasteners. If approved, other AASHTO M 164 bolts may be re-used once.
Touching up or retightening previously-tightened bolts that may have
been loosened by the tightening of adjacent bolts will not be considered
as reuse provided the snugging-up continues from the initial position
and does not require greater rotation, including the tolerance, than
that required by Table 555-7.

Table 555-7 ^(1)^

Nut Rotation from the Snug‑Tight Condition ^(2)^

+-----------------+------------+------------------+------------------+
| **Bolt Length** | **Geometry |                  |                  |
|                 | of Outer   |                  |                  |
| **Measured from | Faces of   |                  |                  |
| Underside**     | Bolted     |                  |                  |
|                 | Parts**    |                  |                  |
| **of Head**     |            |                  |                  |
|                 |            |                  |                  |
| **to End**      |            |                  |                  |
|                 |            |                  |                  |
| **of Bolt**     |            |                  |                  |
+-----------------+------------+------------------+------------------+
|                 | **Both**   | **One Face       | **Both Faces     |
|                 |            | Normal**         | Sloped**         |
|                 | **Faces    |                  |                  |
|                 | Normal**   | **to Bolt Axis   | **Not More Than  |
|                 |            | and**            | 1:20 from Normal |
|                 | **to Bolt  |                  | to**             |
|                 | Axis**     | **Other Face     |                  |
|                 |            | Sloped**         | **Bolt Axis.**   |
|                 |            |                  |                  |
|                 |            | **Not More than  | **(Bevel         |
|                 |            | 1:20 (Bevel      | Washers**        |
|                 |            | Washer**         |                  |
|                 |            |                  | **Not Used)**    |
|                 |            | **Not Used)**    |                  |
+-----------------+------------+------------------+------------------+
| Up to and       | 1/3 turn   | 1/2 turn         | 2/3 turn         |
| including 4     |            |                  |                  |
| diameters       |            |                  |                  |
+-----------------+------------+------------------+------------------+
| Over 4          | 1/2 turn   | 2/3 turn         | 5/6 turn         |
| diameters but   |            |                  |                  |
| not exceeding   |            |                  |                  |
|                 |            |                  |                  |
| 8 diameters     |            |                  |                  |
+-----------------+------------+------------------+------------------+
| Over 8          | 2/3 turn   | 5/6 turn         | 1 turn           |
| diameters but   |            |                  |                  |
| not exceeding   |            |                  |                  |
| 12 diameter     |            |                  |                  |
| ^(3)^           |            |                  |                  |
+-----------------+------------+------------------+------------------+

\(1\) Applicable only to connections where all material within the grip
of the bolt is steel.

\(2\) Nut rotation is relative to bolt, regardless of the element (nut
or bolt) being turned. The tolerance is ±30º for bolts installed by 1/2
turn or less. The tolerance is ±45º for bolts installed by 2/3 turn or
more.

\(3\) Determine the required rotation by actual tests in a suitable
tension device simulating the actual conditions.

**(1) Rotational‑capacity tests.** Subject high‑strength fasteners,
black and galvanized, to job‑site rotational‑capacity tests performed
according to AASHTO M 164 and the following:

*(a)* After tightening to a snug-tight condition, as defined in (c)(3),
tighten the fastener 2 times the required number of turns indicated in
Table 555-7, in a Skidmore‑Wilhelm Calibrator or equivalent tension
measuring device, without stripping or failure.

*(b)* During this test, the maximum recorded tension must be equal to or
greater than the turn test tension that is 1.15 times the required
fastener tension indicated in Table 555-6.

*(c)* The measured torque at a tension \"P,\" after exceeding the turn
test tension required above in *(b)*, shall not exceed the value
obtained by the following equation:

$$\text{Torque}\  = \ 0\text{.}\text{25}\ \text{PD}$$

where:

> Torque = Measured torque in foot·pounds
>
> *P* = Measured bolt tension in pounds
>
> *D* = Nominal bolt diameter in feet

For rotational‑capacity tests, use washers even though their use may not
be required in the actual installation.

**(2) Washers.** Where the outer face of the bolted parts has a slope
greater than 1:20 with respect to a plane normal to the bolt axis, use a
hardened beveled washer to compensate for the lack of parallelism.

Use hardened square or rectangular beveled washers for American Standard
Beams and Channels conforming to AASHTO M 293.

Where necessary, washers may be clipped on one side not closer than 7/8
times the bolt diameter when measured from the center of the washer.

Hardened washers are not required for connections using AASHTO M 164 and
M 253 bolts except under the following conditions:

*(a)* Use hardened washers under the element turned in tightening when
the tightening is done by the calibrated wrench method.

*(b)* Use hardened washers under both the head and the nut when AASHTO M
253 bolts are installed in material having a specified yield point less
than 40 kips per square inch regardless of the tightening method.

*(c)* Use a hardened washer conforming to ASTM F 436 where AASHTO M 164
bolts of any diameter or AASHTO M 253 bolts equal to or less than M24
are to be installed in oversize or short‑slotted holes in an outer ply.

*(d)* Use hardened washers conforming to ASTM F 436, except with
5/16 inch minimum thickness, under both the head and the nut in lieu of
standard thickness hardened washers where AASHTO M 253 bolts over 1 inch
in diameter are to be installed in an oversize or short slotted hole in
an outer ply. Multiple hardened washers with a combined thickness equal
to or greater than 5/16 inch do not satisfy this requirement.

*(e)* Where AASHTO M 164 bolts of any diameter or AASHTO M 253 bolts
equal to or less than 1 inch in diameter are installed in a long-slotted
hole in an outer ply, provide a plate washer or continuous bar of at
least 5/16-inch thickness with standard holes with sufficient size to
cover the slot after installation and is structural grade material that
need not be hardened.

When AASHTO M 253 bolts over 1 inch in diameter are used in long-slotted
holes in external plies, use a single hardened washer conforming to ASTM
F 436 with a 5/16-inch minimum thickness in lieu of washers or bars of
structural grade material. Multiple hardened washers with combined
thickness equal to or greater than 5/16 inch do not satisfy this
requirement.

Alternate design fasteners conforming to Subsection 717.01 with a
geometry that provides a bearing circle on the head or nut with a
diameter equal to or greater than the diameter of hardened washers
conforming to ASTM F 436 satisfy the requirements for washers specified
herein and may be used without washers.

**(3) Turn‑of‑nut tightening.** At the start of work, test nut
tightening using a device capable of indicating bolt tension. Test not
less than 3 bolt-and-nut assemblies of each diameter, length, and grade
to be used in the work. Demonstrate with the test that the method for
estimating snug-tight condition and controlling the turns from snug
tight develops a tension not less than 5 percent greater than the
tension required by Table 555-6. Perform periodic retesting when
required.

Install bolts in all holes of the connection and initially tighten to a
snug-tight condition. Snug tight is defined as the tightness that exists
when the plies of the joint are in firm contact. This may be attained by
a few impacts of an impact wrench or the full effort of a worker using
an ordinary spud wrench.

Systematically snug-tighten bolt groups from the most rigid part of the
connection to the free edges. Then retighten the bolts of the connection
in a similar systematic manner as necessary until all bolts are snug
tight and the connection is fully compacted. Following the
snug-tightening operation, tighten all bolts in the connection by the
applicable amount of rotation specified in Table 555-7.

During all tightening operations, do not allow rotation of the fastener
part not turned by the wrench. Tighten systematically from the most
rigid part of the joint to its free edges.

**(4) Calibrated wrench tightening.** Calibrated wrench tightening may
be used only when installation procedures are calibrated on a daily
basis and when a hardened washer is used under the element turned in
tightening. Standard torques taken from tables or from formulas that
assume to relate torque to tension are not acceptable.

If calibrated wrenches are used for installation, set them to provide a
tension not less than 5 percent in excess of the minimum tension
specified in Table 555-6. Calibrate the installation procedure at least
once each working day for each bolt diameter, length, and grade using
fastener assemblies that are being installed in the work.

Perform the calibration with a device capable of indicating actual bolt
tension by tightening 3 typical bolts of each diameter, length, and
grade from the bolts and washers being installed using a job supplied
washer under the element turned in tightening. Recalibrate wrenches when
significant difference is noted in the surface condition of the bolts,
threads, nuts or washers. Verify during use that the wrench adjustment
selected by the calibration does not produce a nut or bolt head rotation
from snug tight greater than permitted in Table 555-7. Turn nuts in the
tightening direction when measuring the torque of manual torque
wrenches.

If calibrated wrenches are used to install bolts in a connection,
install bolts with hardened washers under the turned element. When
tightening bolts in all holes of the connection, tighten to a snug-tight
condition. Following this initial tightening operation, tighten all
bolts in the connection using a calibrated wrench. Tighten
systematically from the most rigid part of the joint to its free edges.
Touch up previously-tightened bolts that may have been relaxed during
the tightening of adjacent bolts until all bolts are properly tightened.

**(5) Direct tension indicator tightening.** When tightening of bolts
using direct tension indicator devices is used, assemble a
representative sample of not less than 3 devices for each diameter and
grade of fastener to be used in the work in a calibration device capable
of indicating bolt tension. Include in the test assembly flat‑hardened
washers, if required in the actual connection, arranged as those in the
actual connections to be tensioned. The calibration test must
demonstrate that the device indicates a tension not less than 5 percent
greater than that required by Table 555-6.

Follow the manufacturer\'s installation procedures for installation of
bolts in the calibration device and in all connections. Give special
attention to proper installation of flat‑hardened washers when direct
tension indicator devices are used with bolts installed in oversize or
slotted holes and where the load indicating devices are used under the
turned element.

When bolts are installed using direct tension indicators conforming to
ASTM F 959, install bolts in all holes of the connection and bring to a
snug-tight condition. Snug tight is indicated by partial compression of
the direct tension indicator protrusions. After all bolts are
snug-tight, tighten all fasteners systematically from the most rigid
part of the connection to the free edges in a manner that minimizes
relaxation of previously-tightened fasteners. Proper tensioning of the
bolts may require more than a single cycle of systematic partial
tightening before final tightening to deform the protrusion to the
specified gap.

**(6) Installation of alternate design bolts.** When fasteners that
incorporate a design feature intended to indirectly indicate the bolt
tension or to automatically provide the tension required by Table 555-6
and conform to Subsection 717.01 are to be installed, test a
representative sample of not less than 3 bolts of each diameter, length,
and grade on the project with a device capable of indicating bolt
tension.

Include in the test assembly flat‑hardened washers, if required in the
actual connection, arranged as in the actual connections to be
tensioned. The calibration test must demonstrate that each bolt develops
a tension not less than 5 percent greater than the tension required by
Table 555-6. Follow manufacturer\'s installation procedure. Perform
periodic re-testing when required.

When alternate design fasteners that are intended to control or indicate
bolt tension of the fasteners are used, install bolts in all holes of
the connection and initially tighten sufficiently to bring all plies of
the joint into firm contact; but without yielding or fracturing the
control or indicator element of the fasteners. Continue to tighten
systematically from the most rigid part of the connection to the free
edges in a manner that minimizes relaxation of previously-tightened
fasteners.

Proper tensioning of the bolts may require more than a single cycle of
systematic partial tightening before final twist‑off or pull-off of the
control or indicator element of individual fasteners.

**(7) Inspection.** Inspect the tightened bolts in the presence of the
CO. Use an inspection torque wrench to verify tightening of threaded
fasteners. For non-threaded fasteners, ping each fastener with a hammer
to test for soundness. Replace or retighten any loose or relaxed
fastener. Cutting with a torch is not permitted for removal of bolts.

Individually place 3 bolts of the same grade, size, and condition as
those under inspection in a device calibrated to measure bolt tension.
Perform this calibration operation at least once each inspection day.

Use a washer under the part turned in tightening each bolt if washers
are used on the structure. If washers are not used on the structure, use
the same specification material that abuts the part turned in the
tension measuring device as used on the structure. In the calibrated
device, tighten each bolt by any convenient means to the specified
tension. Apply the inspecting wrench to the tightened bolt to determine
the torque required to turn the nut or head 5 degrees, approximately 1
inch at a 12-inch radius, in the tightening direction. Use the average
of the torque required for all 3 bolts as the job-inspection torque.

Select at random in each connection 10 percent (at least two) of the
tightened bolts on the structure represented by the test bolts, and
apply the job-inspection torque to each selected bolt with the
inspecting wrench turned in the tightening direction. If this torque
turns no bolt head or nut, the bolts in the connection will be
considered to be properly tightened. If the torque turns one or more
bolt heads or nuts, apply the job-inspection torque to all bolts in the
connection. Tighten and reinspect any bolt whose head or nut turns at
this stage. As an option, retighten all bolts in the connection and
resubmit for inspection.

**555.18 Welding.** Welding, welder qualifications, prequalification of
weld details, and inspection of welds shall conform to ANSI/AASHTO/AWS
Bridge Welding Code D1.5. Delete the provisions of 9.25.1.7. Do not
underrun the nominal fillet weld size.

Do not weld or tack brackets, clips, shipping devices, or other material
not required to any member unless shown on the accepted drawings.

**555.19 Erection.** Falsework and forms shall conform to Section 562.
Use steel erectors certified under the AISC Quality Certification
Program.

**(a) Handling and storing material.** Place material stored on the
project on skids above ground. Keep material clean and properly drained.
Place and shore girders and beams upright. Support long members, such as
columns and chords, on skids placed near enough together to prevent
damage due to deflection.

**(b) Bearings and anchorages.** Furnish and install bridge bearings
according to Section 564. If the steel superstructure is to be placed on
a substructure that was built under a separate contract, verify that the
masonry has been correctly constructed before ordering material.

**(c) Erection procedures.**

**(1) Conformance to drawings.** Erect according to accepted erection
drawings. Modifications to or deviations from the approved erection
procedure require revised drawings and verification of stresses and
geometry.

**(2) Erection stresses.** Allow for erection stresses induced in the
structure as a result of the use of a method of erection or equipment
that differs from that previously approved and that will remain in the
finished structure as locked-in stresses. Provide additional material,
as needed, to keep both temporary and final stresses within the
allowable limits used in the design.

Provide temporary bracing or stiffening devices to accommodate handling
stresses in individual members or segments of the structure during
erection.

**(3) Maintaining alignment and camber.** During erection, support
segments of the structure in a manner that produces the proper alignment
and camber in the completed structure. Install cross frames and diagonal
bracing as necessary during erection to provide stability and ensure
correct geometry. As necessary, provide temporary bracing at any stage
of erection.

**(d) Field assembly.** Accurately assemble as shown on the erection
drawings and required by match-marks. Carefully handle the material. Do
not hammer, damage, or distort the members. Clean bearing surfaces and
permanent contact surfaces before assembly.

Assemble splices and field connections with at least 2 cylindrical
erection pins per part (4 minimum per splice or connection). A plate
girder splice requires for example, at least 4 cylindrical erection pins
for the top flange splice, 4 pins for the web splice, and 4 pins for the
bottom flange splice. These provide 2 pins for each part. Place the pins
in the corner holes of the splice plates.

Install more cylindrical erection pins, if necessary, to accurately
align the parts. Fill the remaining holes in the connection with bolts,
and tighten systematically from the most rigid part of connection to the
free edges. Remove cylindrical erection pins and replace with tightened
bolts.

Release temporary erection supports at a splice or connection only after
all bolts are installed and tightened. Show special assembly and support
situations on the erection drawings.

Fitting‑up bolts may be the same high‑strength bolts used in the
installation. If other fitting‑up bolts are required, use the same
nominal diameter as the high‑strength bolts. Use cylindrical erection
pins 1/32 inch larger than the bolts.

**(e) Pin connections.** Use pilot and driving nuts in driving pins.
Drive the pins so that the members fully bear on the pins. Screw pin
nuts tight and burr the threads at the face of the nut with a pointed
tool.

**(f) Misfits.** Correction of minor misfits involving minor amounts of
reaming, cutting, and chipping may be done, if approved. Any error in
the shop fabrication or deformation resulting from handling and
transporting will be cause for rejection.

**555.20 Acceptance.** Material (except bearing devices and painting)
for steel structures will be evaluated under Subsections 106.02 and
106.03. Furnish production certifications for each shipment of
structural steel, steel forgings, and high-strength bolts, nuts, and
washers.

Construction of steel structures will be evaluated under Subsections
106.02 and 106.04.

Bearing devices will be evaluated under Section 564.

Painting will be evaluated under Section 563.

Measurement

**555.21** Measure the Section 555 items listed in the bid schedule
according to Subsection 109.02 and the following as applicable.

Measure structural steel computed according to the AASHTO *Standard
Specifications for Highway Bridges.* Include all metal items incidental
to the structure and required by the contract such as castings, steel
plates, anchor bolts and nuts, bearings, rockers, rollers, pins and
nuts, expansion dams, roadway drains and scuppers, weld metal, bolts
embedded in concrete, cradles and brackets, posts, conduits and ducts,
and structural shapes.

When measurement is by contract quantity, changes in quantities
resulting from alternative details proposed by the Contractor and
accepted as a part of the drawings are not subject to adjustment
according to Subsection 109.05.

Payment

**555.22** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 555 pay item listed in the bid
schedule. Payment will be full compensation for the work prescribed in
this Section. See Subsection 109.05.

## Section 556. --- BRIDGE RAILING

Description

**556.01** This work consists of furnishing, erecting, removing, and
resetting bridge railing.

Bridge railing is designated as concrete, steel, aluminum, or timber
according to the predominant material contained in the railing.

Material

**556.02** Conform to the following Sections and Subsections:

Aluminum bolt heads and nuts 717.14

Aluminum alloy for bridge rail 717.13

Aluminum-impregnated caulking compound 725.28

Aluminum welding wire 717.15

Box beam rail 710.07

Concrete 552

Painting 563

Reinforcing steel 709.01

Structural steel 555

Timber 557

Construction Requirements

**556.03 General.** Accurately place anchor bolts to provide correct and
true alignment of the railing. Set anchor bolts so that they project not
more than 3/8 inch beyond the nut when tightened. Chamfer or round by
grinding or filing all sharp exposed metal edges.

Do not erect railing until centering or falsework for the supporting
span is removed. Construct bridge railing so that it does not follow any
unevenness in the curb, sidewalk, or wall that supports the railing. The
railing shall present a smooth, uniform appearance in its final
position. Set all posts vertical.

**556.04 Concrete Railing.** Construct according to Section 552.

**556.05 Steel Railing.** Construct according to Section 555.

**556.06 Aluminum Railing.** Construct according to Section 555 except
as amended by the following:

**(a) Cutting.** Material that is 1/2 inch thick or less may be cut by
shearing, sawing, or milling. Saw or mill material that is over 1/2 inch
thick. Do not flame cut. Make cut edges true, smooth, and free from
excessive burrs or ragged breaks. Fillet reentrant cuts by drilling
before cutting.

**(b) Bending.** Material may be heated to a maximum 400 ºF for a period
not to exceed 30 minutes to facilitate bending.

**(c) Rivet and bolt holes.** Drill rivet and bolt holes to finished
size, or subpunch smaller than the nominal diameter of the fastener and
ream to size. Subpunch to a diameter that is smaller than that of the
finished hole by at least one quarter the thickness of the piece. Make
the finished diameter of holes not more than 7 percent greater than the
nominal diameter of the fastener except:

**(1)** Fabricate slotted bolt holes as required; and

**(2)** Fabricate anchor bolt holes up to 25 percent larger, not to
exceed 1/2 inch larger than the nominal bolt diameter.

**(d) Welding.** Weld according to AWS Structural Aluminum Welding Code
D1.2.

**(e) Contact with other material.** Do not place aluminum alloys in
contact with copper, copper base alloys, lead, or nickel. Where aluminum
alloys come in contact with other metals, coat the contacting surfaces
thoroughly with an aluminum‑impregnated caulking compound or place a
neoprene gasket between the surfaces.

Where aluminum alloys come in contact with concrete or stone, coat the
contacting surfaces with an aluminum‑impregnated caulking compound. When
bond between aluminum and concrete is required, coat the aluminum with
zinc‑chromate paint and allow to dry before installation.

Where aluminum alloys come in contact with wood, coat the contacting
wood surface with 3 coats of paint according to Section 563 and coat the
contacting aluminum surface with an aluminum caulking compound.

**556.07 Timber Railing.** Construct according to Section 557.

**556.08 Remove and Reset Bridge Railing.** Remove and store the
existing bridge railings and appurtenances. Replace all railings,
supports, and hardware damaged during removal, storage, or resetting.

**556.09 Painting.** Where required by the contract, paint according to
Section 563.

**556.10 Acceptance.** Material (except concrete, painting, reinforcing
steel, structural steel, and timber) for bridge railings will be
evaluated under Section 106.03. Furnish a production certification with
each shipment of bridge railing.

Concrete will be evaluated under Section 552 except compressive strength
will be evaluated under Subsection 106.04.

Painting will be evaluated under Section 563.

Reinforcing steel will be evaluated under Section 554.

Structural steel will be evaluated under Section 555.

Timber will be evaluated under Section 557.

Construction of bridge railings will be evaluated under Subsections
106.02 and 106.04.

Measurement

**556.11** Measure the Section 556 items listed in the bid schedule
according to Subsection 109.02.

Payment

**556.12** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 556 pay items listed in the bid
schedule. Payment will be full compensation for the work prescribed in
this Section. See Subsection 109.05.

## Section 557. --- TIMBER STRUCTURES

Description

**557.01** This work consists of furnishing, preparing, erecting, and
painting structural timber. It also includes all required yard lumber
and hardware.

Material

**557.02** Conform to the following Section and Subsections:

Hardware 716.02

Painting 563

Structural glued laminated timber 716.04

Treated structural timber and lumber 716.03

Untreated structural timber and lumber 716.01

Construction Requirements

**557.03 General.** Excavate and backfill according to Section 209.

Furnish structural lumber and timber of the required stress grade.

Clear the ground under and in the vicinity of all stored material of
stacks of weeds, rubbish, or other objectionable material. Place the
bottom layer of material at least 8 inches above the ground level.
Provide sufficient support to prevent sagging.

Open-stack untreated material to shed water. Stack material in layers on
spacers (stickers) that extend across the full width of the stack to
allow for free air circulation. Align all stickers vertically and space
them at regular intervals.

Close-stack treated material to shed water.

Protect material from the weather. If covered, use sheet material such
as water-resistant paper or opaque polyethylene film. Do not cover with
impervious membranes such as polyethylene film during dry weather. Slit
individual wrappings full length or puncture on the lower side to permit
drainage of water.

Store and protect glued laminated timber according to the
recommendations for unloading and handling, job site storage, and
erection in "Recommended Practice for Protection of Structural Glued
Laminated Timber During Transit, Storage, and Erection," AITC 111.

Use slings or other devices to protect corners of heavy construction
timbers and banded packages of lighter construction timber.

Cut and form all lumber and construction timber so all joints will have
even bearing over the entire contact surface. Do not use shims in making
joints. Construct all joints to be closed. Drive nails and spikes to set
the heads flush with the wood surface.

Use the same end, face, and edge of the timber member for all layout
dimensions. Bore all holes from mating faces.

**557.04 Treated Timber.** Fabricate timbers before treatment. Handle
treated timber according to the Consumer Information Sheet published by
the AWPA. Handle treated timbers carefully and do not drop, damage outer
fibers, or penetrate the surface with tools. Do not use cant dogs,
hooks, or pike poles. In coastal waters, do not cut or bore timber below
the high-water mark.

Carefully trim all field cuts or abrasions made in fabricated timber
after treatment. Dip, soak, spray or apply three brush coats of a copper
naphthenate solution prepared in accordance with AWPA M4. Apply the
preservative in such a manner that it does not drip or spill into the
aquatic environment or onto the soil.

Impregnate all holes bored after treatment with the same preservative
using equipment suitable for proper application of the preservative.
Plug all unused holes with preservative treated plugs.

**557.05 Holes for Bolts, Dowels, Rods, and Lag Screws.** Bore all holes
before preservative treating the wood. Bore holes for round drift pins
and dowels to the same diameter as the dowel or pin. Bore holes for
square drift pins and dowels to a diameter equal to the side dimension
of the pin or dowel.

Bore holes for galvanized bolts to 1/8 inch larger than the diameter of
the bolt.

Bore holes for lag screws according to Subsection 7.3.1. of the AITC
*Timber Construction Manual.*

**557.06 Bolts and Washers.** Galvanize hardware and fasteners including
nails, spikes, bolts, washers, and timber connectors. Do not galvanize
malleable iron or cast-iron hardware or fasteners.

Use washers under all bolt heads and nuts in contact with wood. Use
malleable iron washers with a diameter approximately three times the
bolt diameter. Use cast-iron washers when the timber is in contact with
the ground. Use square washers only when indicated on the contract
plans.

Cut off excess bolt lengths of more than an inch. After final
tightening, check or burr all bolts with a pointing tool to prevent
loosening of the nuts.

**557.07 Countersinking.** Countersink nuts and bolt heads where
required by the contract. Paint recesses formed for countersinking,
except in railings, with an approved preservative. After bolts or screws
are in place, fill the holes with hot pitch or other approved filler.

**557.08 Framing.** Do not slab or trim treated piles for fitting sway
or sash braces. Fill all gaps that occur between braces and piles with
treated blocks so that the bracing is securely fastened to the piles.

**557.09 Framing Bents.** Bed mud sills firmly and evenly to solid
bearing and tamp in place.

When concrete is cast, set dowels for anchoring sills and posts to
project at least 6 inches above the tops of the pedestals. Carefully
finish concrete pedestals supporting framed bents so that sills or posts
bear evenly on the pedestals.

Provide firm, even bedding for mud sills. Make sills bear true and even
on mud sills, piles, or pedestals. Drift bolt sills with bolts that
extend into the mud sills or piles for at least 6 inches. Where
possible, remove all earth in contact with sills for circulation of air
around the sills.

**557.10 Caps for All Bents.** Make timber caps bear evenly and
uniformly over the tops of the supporting posts or piles with their ends
in alignment. Secure all caps with driftbolts and set approximately at
the center of and extending into the posts or piles at least 9 inches.

**557.11 Bracing.** Bolt the ends of bracing through the pile, post,
cap, or sill. Brace intermediate intersections with posts or piles with
bolts or spikes with wire or boat spikes, as required. In all cases use
galvanized spikes in addition to bolts.

Make all bracing bear firmly against the pile or cap to which it is
bolted. Provide and place shims as necessary to prevent bending the
bracing more than 1 inch out of line when bracing bolts are tightened.

Where the space between the bracing and cap or pile is less than 1 inch,
shims need not be used. Where the space between the bracing and the cap
or pile is 1½±1/2 inches, place 2 ogee washers with their narrow faces
together or other approved washers on each bolt that passes through the
space.

Where the space between the bracing and the cap or pile is over 2
inches, use wooden shims of the proper thickness. Fabricate the wooden
shims from white oak or from the same treated wood used in the
structure. Do not use built-up wooden shims. Make wooden shims from a
single piece of lumber with the width not less than 4 inches and the
length not less than the width of the bracing measured along the cap or
pile. Do not adze, trim, or cut any treated member to avoid the use of
shims.

**557.12 Stringers.** Size stringers at bearings and place in position
so that knots near edges are in the top portions of the stringers.

Outside stringers may have butt joints with the ends cut on a taper. Lap
interior stringers to take bearing over the full width of the floor beam
or cap at each end. Separate the lapped ends of untreated stringers by
at least 1/2 inch for air circulation. Securely fasten the lapped ends
with drift bolts as required. Stagger the joints where stringers are
2 panels in length.

Securely toenail cross-bridging between stringers with at least 2 nails
in each end. Cut all cross‑bridging members for a full bearing at each
end against the sides of the stringers. Place cross‑bridging at the
center of each span. If blocking is used, make it fit snugly and hold in
place as required.

**557.13 Plank Floors.** Use plank that is surfaced on four sides (S4S).

Single-ply timber floors consist of a single thickness of planks
supported on stringers. Lay the planks heart side down with 1/4 inch
space between them for seasoned material and with tight joints for
unseasoned material. Spike each plank securely to each stringer.
Carefully grade the planks as to thickness and lay so that no 2 adjacent
planks vary in thickness by more than 1/16 inch.

Two‑ply timber floors consist of 2 layers of flooring supported on
stringers. Treat the lower layer according to Subsection 557.04. Lay the
top layer either diagonally or parallel to the centerline of roadway as
required. Securely fasten each floor piece to the lower layer. Stagger
joints at least 3 feet. Where the top layer is placed parallel to the
centerline of the roadway, use special care to securely fasten the ends
of the flooring. Bevel the ends of top layer members at each end of the
structure.

**557.14 Transversely Nail-Laminated Decks.** Use 2-inch nominal
thickness laminations, surface one edge hit or miss 1/8 inch scant
(SIE‑H or M 1/8-inch scant), and one side hit or miss 1/8 inches scant
(SIS‑H or M 1/8-inch scant).

Place the laminations on edge and at right angles to the centerline of
roadway. Spike each piece to the preceding piece at each end and at
approximately 18-inch intervals with the galvanized spikes driven
alternately near the top and bottom edges. Use spikes of sufficient
length to pass through 2 pieces and at least halfway through the third
piece.

Where timber stringers are used, use spikes to toenail every other piece
to every other stringer. When steel stringers are used, securely attach
the pieces using approved galvanized metal clips.

Use pieces of sufficient length to bear on at least 4 stringers. Do not
splice pieces between stringers. Space end joints on any one stringer no
closer than every third piece. Space end joints in adjoining pieces no
closer than every second stringer.

**557.15 Wheel Guards and Railings.** Surface (S4S) wheel guards, rails,
and posts. Place wheel guards in sections not less than 12 feet in
length. Squarely butt‑joint all rails at posts.

**557.16 Trusses.** Fabricate trusses to show no irregularities of line
when completed. Fabricate chords straight and true from end-to-end in
horizontal projection. In vertical projection, fabricate chords to a
smooth, corded curve through panel points conforming to the correct
camber. Do not make uneven or rough cuts at the points of bearing.

**557.17 Drains.** Hot-dip galvanize drains, including anchorages, after
fabrication.

**557.18 Painting.** When paint is specified in the contract, paint
according to Section 563.

**557.19** **Acceptance.** Material (except paint) for timber structures
will be evaluated under Subsections 106.02 and 106.03. Furnish a
production certification with each shipment of structural timber and
lumber.

Construction of timber structures will be evaluated under Subsections
106.02 and 106.04.

Painting will be evaluated under Section 563.

Measurement

**557.20** Measure the Section 557 items listed in the bid schedule
according to Subsection 109.02 and the following as applicable.

Measure untreated and treated structural timber and lumber by the
thousand feet board measure (MFBM) in the structure.

Compute the quantities from nominal dimensions and actual lengths except
for transversely nail-laminated decks. Measure transversely
nail-laminated decks in place after dressing.

Measure timber piles under Section 551.

Measure timber bridge rail under Section 556.

Payment

**557.21** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 557 pay items listed in the bid
schedule. Payment will be full compensation for the work prescribed in
this Section. See Subsection 109.05.

## Section 558. --- DAMPPROOFING

Description

**558.01** This work consists of dampproofing concrete or masonry
surfaces.

Material

**558.02** Conform to the following Subsections:

Asphalt 702.05(b)

Primer 702.05(a)

Construction Requirements

**558.03 Dampproofing.** Cure the concrete or masonry surface according
to Subsection 552.15 except do not use liquid membrane curing compound.
Allow concrete surface to dry at least 10 days after completion of
curing.

Apply dampproofing to a dry, clean, reasonably smooth surface that is
free of dust and loose material. Apply dampproofing in dry weather when
the air and surface temperatures are 45 ºF or higher.

Apply primer to the surface and allow it to dry. Apply 2 coats of
asphalt at the rate of approximately 25 pounds per 100 square feet of
surface per coat. Apply prime coat and asphalt coats uniformly, fully
covering the surface, and thoroughly work them into the surface. Make
the total of the final 2 asphalt coats approximately 3/32 inch thick.
Allow asphalt coats to harden before allowing contact with water or
backfill material.

**558.04 Acceptance.** Material for dampproofing will be evaluated under
Subsections 106.02 and 106.03.

Applying dampproofing will be evaluated under Subsections 106.02 and
106.04.

Measurement

**558.05** Measure the Section 558 items listed in the bid schedule
according to Subsection 109.02.

Payment

**558.06** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 558 pay items listed in the bid
schedule. Payment will be full compensation for the work prescribed in
this Section. See Subsection 109.05.

## Section 559. --- WATERPROOFING

Description

**559.01** This work consists of waterproofing concrete surfaces with a
firmly-bonded membrane and, when specified, protecting with a mortar or
asphalt plank overlay.

Protection types are designated as follows:

Type 1--- Mortar overlay.

Type 2--- Asphalt plank overlay.

Material

**559.02** Conform to the following Subsections:

Asphalt 702.05(b)

Asphalt plank 702.05(e)

Asphalt roll roofing 702.05(f)

Joint filler 712.01

Mortar 702.05(d)

Primer 702.05(a)

Waterproofing fabric 702.05(c)

Welded wire fabric 709.01

Construction Requirements

**559.03 Membrane Waterproofing.** Make the concrete surface smooth and
free of projections or depressions that might cause puncture of the
membrane. Allow concrete surfaces to dry at least 10 days after
completion of curing. Make the surface dry and free of dust and loose
material. Apply waterproofing in dry weather when the temperature is
above freezing. Apply primer and allow to dry.

Begin at the lowest point of the concrete surface and apply a mop coat
of asphalt slightly wider than half the width of fabric. Apply asphalt
at a temperature between 300 and 350 ºF. Apply so no uncoated areas of
concrete remain.

Lay fabric so that drainage is over and not against or along the laps.
Lay a half width of fabric on the asphalt and press into place expelling
all entrapped air and obtaining close contact with the surface.

Mop coat the top of the first strip so as to completely conceal the
weave and an adjoining section of concrete surface slightly wider than
half the fabric width. On this mopping, lay a full-width strip of fabric
and press into place completely covering the first strip. Mop this
second strip and an adjoining section of concrete surface slightly wider
than half the fabric width. Place a third strip of fabric so as to lap
the first strip by not less than 4 inches. Continue this process of
lapping each strip of fabric at least 4 inches over the strip placed
before the last strip until the entire surface is covered with 2 layers
of fabric. Lap the ends at least 12 inches. Do not allow the fabric to
touch an unmopped surface.

Mop the entire surface with hot asphalt after all fabric is placed.
Apply asphalt at a rate not less than 12 gallons per 100 square feet of
finished horizontal surface and not less than 15 gallons per 100 square
feet of vertical surface. Regulate work so, at the close of a day\'s
work, all fabric in place is mopped. Take special care to ensure that
all laps are sealed.

At the edges of the membrane and at places where it is punctured by
openings such as for drains or pipes, prevent water from getting between
the waterproofing and the waterproofed surface.

Provide flashing at curbs and against girders, spandrel walls, etc. with
separate sheets that lap the main membrane at least 12 inches. Seal
flashing with either a metal counterflashing or by embedding the upper
edges of the flashing in a groove joint filler.

Repair or replace any membrane waterproofing that is found to leak.
Sampling frequency and location where samples are to be taken will be
specified in the contract.

Apply protective covering or backfill to prevent damage.

**559.04 Membrane Waterproofing with Mortar Protection.** Construct
waterproofing membrane to be protected with mortar according to
Subsection 559.03.

Completely cover the membrane, except on undercut surfaces, with a
course of reinforced mortar.

Use a 2-inch thick mortar course reinforced with welded wire
reinforcement (W5.5 by W5.5) or its equivalent placed midway between the
top and bottom surfaces of the mortar. Trowel the top surface of the
mortar course to a smooth, hard finish. Cure the protective mortar with
wet burlap held in close surface contact for 72 hours.

Protect undercut membrane surfaces with a layer of asphalt roll roofing
laid in hot asphalt in place of the mortar covering. Use the same
bituminous material as used for mopping the membrane.

**559.05 Membrane Waterproofing with Asphalt Plank Protection.**
Construct waterproofing membrane with asphalt plank protection according
to Subsection 559.03.

Cover the membrane with asphalt plank. Lay the plank in regular,
straight courses as required. Use whole planks in all cases except as
required for closures and for fitting around openings and obstructions.
Carefully cut to size closing and trimming pieces. Before the planks are
laid, remove all surplus talc or other powder from the planks with a
stiff brush or broom. Lay each piece in a mopping of hot asphalt, and
coat the edges and ends of pieces in place with hot asphalt before
placing an adjacent piece in contact. Press each individual piece
tightly against the piece next to it. Make the completed surface uniform
and smooth without open joints.

**559.06 Acceptance.** Material for waterproofing will be evaluated
under Subsections 106.02 and 106.03.

Applying waterproofing will be evaluated under Subsections 106.02 and
106.04.

Measurement

**559.07** Measure the Section 559 items listed in the bid schedule
according to Subsection 109.02.

Payment

**559.08** The accepted quantities will be paid at the contract price
per unit of measurement, for the Section 559 pay items listed in the bid
schedule. Payment will be full compensation for the work prescribed in
this Section. See Subsection 109.05.

## Section 560. --- REMOVAL OF CONCRETE BY HYDRODEMOLITION

Description

**560.01** This work consists of removing concrete with high pressure
water jets.

Material

**560.02** Conform to the following Subsection:

Water 725.01(c)

Construction Requirements

**560.03 General.** Submit a proposed sequence and schedule to the CO
for acceptance. Include the proposed removal method, list of removal
equipment, and equipment operator certifications.

Submit the proposed method for filtering wastewater. Use methods such as
filters and sediment traps to ensure that wastewater released into the
environment is free of concrete particles and sediment. Dispose of all
debris off the project according to Subsection 203.05.

Construct structurally-adequate debris shields to prevent debris and
wastewater from entering waterways, travel lanes open to public traffic,
or areas designated not to be disturbed.

Furnish all water required to operate the hydrodemolition equipment.

**560.04 Equipment.** Furnish a self-propelled and completely
programmable hydrodemolition system designed for concrete removal to
precise depths. Provide qualified equipment operators certified by the
equipment manufacturer.

Demonstrate and calibrate the hydrodemolition equipment in a 60-square
yard test area identified by the CO. Establish the operating parameters
to achieve the required depth of removal. Submit the complete list of
operating parameters to be used for production work to the CO for
approval.

**560.05 Concrete Removal.** In the presence of the CO, use a hammer,
chain, or other acceptable means to test the concrete surface and
determine the soundness of the concrete. Identify and mark all concrete
to be removed at least one day in advance of the hydrodemolition
operation.

Using hydrodemolition equipment, remove the designated concrete to a
minimum depth of 1 inch below the bottom of the top mat of reinforcing
steel. If needed, recalibrate the equipment during production to obtain
satisfactory concrete removal. Also remove all loose and unsound
concrete below the minimum depth.

In areas inaccessible to the hydrodemolition equipment, use acceptable
hand-held water blasting equipment or power-driven hand tools such as
jack hammers, mechanical chipping tools, or chipping hammers to remove
the designated concrete.

Do not damage remaining sound concrete or reinforcing steel. When the
bond between existing concrete and reinforcing steel is destroyed,
remove the concrete adjacent to the reinforcing steel to a depth that
permits new concrete to bond to the entire periphery of the reinforcing
steel.

If necessary, use hand tools such as hammers and chisels to remove the
final particles of concrete to achieve the required depth. Leave a rough
surface after the concrete is removed. Remove debris immediately after
the demolition operation to prevent it from rebonding to the surface or
reinforcing steel.

**560.06 Reinforcing Steel.** Do not cut or damage reinforcing steel
designated to remain. Use methods acceptable to the CO to repair or
replace all reinforcing steel damaged by the concrete removal operation.

**560.07 Surface Preparation.** Before placing new concrete, clean the
concrete surface and all exposed reinforcing steel of all rust, loose
and rebounded material, and other contaminants that may inhibit a bond
with new concrete. If compressed air is used, provide a filter in the
air line to ensure that the air delivered is oil-free. Protect the steel
and surface from contamination until the new concrete is placed.

**560.08 Acceptance.** Removal of concrete by hydrodemolition will be
evaluated under Subsection 106.02.

Measurement

**560.09** Measure the Section 560 items listed in the bid schedule
according to Subsection 109.02 and the following as applicable.

Measure hydrodemolition by the cubic foot in its original position.

Payment

**560.10** The accepted quantity measured as provided in Subsection
109.02, will be paid at the contract price per unit of measurement for
the Section 560 pay item listed in the bid schedule. Payment will be
full compensation for the work prescribed in this Section. See
Subsection 109.05.

## Section 561. --- Reserved

## Section 562. --- TEMPORARY WORKS

Description

**562.01** This work consists of the design, construction, inspection,
and removal of temporary works for the construction and repair of
permanent structures. Temporary works includes all temporary facilities
used in construction that do not become part of the permanent structure.
Such temporary works include, but are not limited to, falsework,
formwork, cofferdams, and excavation supports.

Material

**562.02** Select material consistent with the safety and quality
required by the design assumptions. Furnish manufactured devices
complying with the *Certification Program for Bridge Temporary Works*
(FHWA-RD-93-033).

Design Requirements

**562.03 Design.** Design and construct safe and adequate temporary
works that will support all loads imposed and provide the necessary
rigidity to produce in the final structure, the lines and grades shown
on the plans. Design temporary works according to the *AASHTO Guide
Design Specification for Bridge Temporary Works*. When a manufactured
device is to be employed, ensure that the design load on the device is
within the load rating recommended by the manufacturer. Design falsework
and forms supporting deck slabs and overhangs on girder bridges so that
there will be no differential settlement between the girders and the
deck forms during placement of deck concrete.

For cast-in-place concrete structures, limit the calculated deflections
of falsework and formwork members as follows:

**(a)** Falsework members vertical deflection: 1/360 of the span under
the dead load of the concrete only, regardless of the fact that
deflection may be compensated for by camber strips.

**(b)** Formwork (other than sheathing): 1/360 of the span under the
dead load of the concrete only or the lateral pressure of fluid concrete
only.

**(c)** Formwork (sheathing): 1/8 inch or 1/270 of the center-to-center
distance between studs, joists, form stiffeners, form fasteners, or
wales.

Design falsework and forms for concrete supported on steel structures so
that loads are applied to girder webs within 6 inches of a flange or
stiffener. Distribute the loads in a manner that does not produce local
distortion of the web. Brace or tie exterior girders, upon which
overhanging bridge deck falsework brackets are hung, to the adjacent
interior girders as necessary to prevent rotation of exterior girders or
overstressing the exterior girder web. Do not use deck overhang forms
that require holes to be drilled into the girder webs.

Do not use deck overhang form brackets for steel girder bridges that
require holes to be cast or drilled into the girder webs.

Do not apply loads to existing, new, or partially completed structures
that exceed the load carrying capacity of any part of the structure
according to the load factor design methods of the AASHTO Bridge Design
Specifications using load group IB.

Do not use permanent or stay-in-place deck forms unless specified in the
contract.

**562.04 Drawings.** Prepare and submit drawings according to Subsection
104.03. Furnish design calculations and supporting data in sufficient
detail to permit a structural and safety review of the proposed design.
Show all information necessary to allow the design of all components to
be checked independently. When manufactured devices are used as part of
the temporary works, provide catalog or equivalent data indicating the
device's recommended safe load capacity.

When concrete placement is involved, indicate on the drawings the
proposed sequence, rate of placement, direction of placement, and
location of all construction joints. Show anticipated total settlements
and deflections of the falsework and forms on the drawings. Include
falsework footing settlements, joint take-up, and deflection of beams or
girders.

For steel girder erection, submit the erection procedure and temporary
support system. Include calculations in sufficient detail to
substantiate that the girder geometry is correct. Design supporting
falsework to accommodate the erection procedure without over stressing
the structural steel and to produce the required final structural
geometry, intended continuity, and structural action.

Do not start construction of any temporary work for which drawings are
required until the CO has accepted the drawings.

Construction Requirements

**562.05 Foundations.** Determine the allowable bearing capacity of the
foundation material on which the supports for temporary works will rest.
Perform load tests to verify proposed bearing capacity values that are
in doubt, marginal or in other high risk situations.

Foundation support values shown in the contract for the permanent
structure may be used in the design of falsework foundations provided
foundations are at the same elevation and on the same soil as those of
the permanent structure. If temporary works are to be supported on
temporary fill, construct the fill according to Section 204 and verify
the bearing capacity of the placed material.

Do not locate the edge of footings closer than 12 inches from the
intersection of the bench and the top of the slope. Unless shoring
adequately supports the excavation for footings, do not locate the edge
of the footings closer than 48 inches or the depth of excavation;
whichever is greater, from the edge of the excavation.

Provide adequate site drainage and soil protection to ensure the
integrity of the foundation material for the temporary works supports.

If piles are used, capacities may be estimated and later confirmed
during construction using standard procedures based on the driving
characteristics of the pile. In the absence of more sophisticated
methods of determining pile capacity, use the dynamic formula according
to Section 551 to determine ultimate pile capacity. The Contractor may
elect to use load tests to confirm the estimated capacities. Perform
load tests to verify bearing capacity values that are in doubt, marginal
or in other high risk situations.

Submit all foundation design calculations and other relevant foundation
design data to the CO for acceptance.

**562.06 Construction.** Construct temporary works according to the
accepted drawings. Use material and workmanship consistent with that
assumed in the design of the temporary works.

Do not weld temporary works or use driven devices to fasten temporary
works to any portion of the permanent structure unless it is shown on
the accepted drawings.

Furnish and place form panels for exposed surfaces in uniform widths of
not less than 3 feet and in uniform lengths of not less than 6 feet
except where the width of the member formed is less than 3 feet. Arrange
panels in symmetrical patterns conforming to the general lines of the
structure. Place panels for vertical surfaces with the long dimension
horizontal and with horizontal joints level and continuous. For walls
with sloping footings, which do not abut other walls, panels may be
placed with the long dimension parallel to the footing. Precisely align
form panels on each side of the panel joint by means of supports or
fasteners common to both panels.

Devices may be cast into the concrete for later use in supporting forms
or for lifting precast members. Do not use driven devices for fastening
forms or form supports to concrete. Use form ties consisting of form
bolts, clamps, or other devices necessary to prevent spreading of the
forms during concrete placement. Do not use form ties consisting of
twisted wire loops.

When architectural treatment is required, make the angle points for
chords in wall stems fall at vertical rustication joints. Form exposed
curved surfaces to follow the shape of the curve except on retaining
walls that follow a horizontal curve. The wall stems may be a series of
short chords if all of the following apply:

**(a)** Chords within the panel are the same length;

**(b)** Chords do not vary from a true curve by more than 1/2 inch at
any point; and

**(c)** All panel points are on the true curve.

Provide tell-tales with surveyed measurements, or other acceptable
means, for accurate measurement of falsework settlement. Do not use the
ground surface near falsework supports as a reference elevation. During
concrete placement, record settlement to the nearest 1/8 inch.

Discontinue concrete placement and take corrective action if settlement
or deflections occur that deviate more than 3/8 inch from those shown on
the falsework drawings.

If satisfactory corrective action is not taken before initial set,
remove all unacceptable concrete.

**562.07 Maintenance and Inspection.** Inspect and maintain temporary
works in an acceptable condition throughout the period of use. Clearly
mark the capacity of each manufactured device according to the
*Certification Program for Bridge Temporary Works* (FHWA-RD-93-033).

In the presence of the CO, perform an in-depth inspection of the
temporary works not more than 24 hours before beginning each concrete
placement or before allowing people to enter a cofferdam or excavation
support structure. Inspect other temporary works at least once a month
to ensure they are functioning properly. Use a registered professional
engineer to inspect cofferdams, shoring, support of excavation
structures, and support systems for load tests before loading.

Make inspections and certifications according to the *Certification
Program for Bridge Temporary Works* (FHWA-RD-93-033). Furnish written
results of the inspections to the CO before placing concrete, allowing
people to enter a cofferdam or excavation support structure, or loading
temporary works. Include a certification that the system meets the
requirements of the contract and drawings.

**562.08 Removal.** Remove all temporary works except as follows:

**(a)** Portions of driven falsework piles that are more than 12 inches
below subgrade within roadbeds, 24 inches below the original ground or
finished grade outside of roadbeds, or 24 inches below the established
limits of any navigation channel;

**(b)** Footing forms where their removal would endanger the safety of
cofferdams or other work; and

**(c)** Forms from enclosed cells where access is not provided.

Remove temporary works in such a manner as to permit the structure to
uniformly and gradually take the stresses due to its own mass.

Unless otherwise permitted, remove all temporary works upon completion
of the work. Do not disturb or damage the finished work. Restore the
area to its original or planned condition. Clean up all debris. The
removed temporary works remain the property of the Contractor.

Forms that do not support the dead load of concrete members and forms
for railings and barriers may be removed 24 hours after the concrete is
placed, excluding forms for cold weather concrete, and provided that the
concrete has sufficient strength to prevent damage to the surface.
Remove cold weather concrete forms only after the strength of the
concrete has reached at least 500 pounds per square inch. When forms are
removed at less than 7 days after concrete placement cure concrete
according to Subsection 552.15.

Forms supporting the dead load of concrete members may be removed only
after the concrete has reached 90% of the design compressive strength
and has been in place for at least 7 days.

Falsework supporting any span of a simple span bridge may be removed
only after the concrete, excluding concrete above the bridge deck, has
reached 90% of the design compressive strength and has been in place for
at least 10 days.

Falsework supporting any span of a continuous or rigid frame bridge may
be removed only after the concrete in that span and the concrete in the
adjacent portions of each adjoining span for a length equal to at least
one-half the length of the span where the falsework is to be released
meets the requirements for simple span bridges.

Do not release falsework for post-tensioned portions of structures until
after the prestressing steel has been tensioned.

Remove falsework for arch bridges uniformly and gradually. Begin at the
crown and work toward the springing points. Remove falsework for
adjacent arch spans simultaneously.

Install a reshoring system if falsework supporting the sides of girder
stems with slopes steeper than 1V:1H are removed before placing deck
slab concrete. Design the reshoring system with lateral supports, which
resist all rotational forces acting on the stem, including those caused
by the placement of deck slab concrete. Install the lateral supports
immediately after each form panel is removed and before release of
supports for the adjacent form panel.

**562.09 Acceptance.** Temporary works will be evaluated under
Subsections 106.02, 106.03, and 106.04.

Measurement and Payment

**562.10** See Subsection 109.05.

Do not measure temporary works for payment.

## Section 563. --- PAINTING

Description

**563.01** This work consists of removing coatings and applying
protective coatings to metal, timber, or concrete surfaces to control
corrosion and deterioration.

Material

**563.02** Conform to the following Section and Subsections:

Linseed oil 725.14

Mineral spirits 725.14

Paint 708

Water 725.01

Construction Requirements

**563.03 Protection of Public, Property, and Workers.** Comply with the
Steel Structures Painting Council\'s (SSPC) *SSPC-PA Guide 3 --- A Guide
to Safety in Paint Application* and OSHA requirements. If the paint
being removed is a hazardous material containing lead or chromium,
comply with all the following:

• SSPC Guide 6I(CON) --- Guide for Containing Debris Generated During
Paint Removal Operations;

• SSPC Guide 7I(DIS) --- Guide for the Disposal of Lead-Contaminated
Surface Preparation Debris;

• 29 CFR 1926.62 --- OSHA Construction Industry Standards for Lead;

• 40 CFR 50.6 --- EPA National Primary and Secondary Ambient Air Quality
Standards for Particulate Matter;

• 40 CFR 50.12 --- EPA National Primary and Secondary Ambient Air
Quality Standards for Lead; and

• 40 CFR Parts 260-268 --- Resource Conservation and Recovery Act
(RCRA).

At least 28 days before beginning surface preparation, submit a written
plan for acceptance that details the measures to be used for protecting
the environment, public, adjacent property, and workers. Include in the
plan the following:

**(a)** Manufacturer\'s material safety data sheets and product data
sheets for all cleaning and painting products.

**(b)** A detailed containment plan for removed material, cleaning
products, and paint debris. Include details of attachment that do not
require welding or drilling holes in the existing structure. Make
connections with clamps or other approved devices.

**(c)** A detailed disposal plan for removed material, cleaning
products, and paint debris.

**(d)** Specific safety measures to protect workers from site hazards
including falls, fumes, fires, or explosions.

**(e)** If paint being removed is a hazardous material, include specific
safety measures to comply with 29 CFR 1926.62, 40 CFR 50.6, 40 CFR
50.12, and 40 CFR Parts 260-268. Document compliance upon request.

**(f)** Emergency spill procedures.

**(g)** To perform quality control functions, provide a competent person
as defined in SSPC-QP 2 with the following:

**(1)** An SSPC Competent Person Certificate;

**(2)** A certificate of completion of 29 CFR 1926.62 Lead in
Construction training;

**(3)** Minimum of 2 years industrial field painting experience;

**(4)** Minimum of 90 days of field supervisory or management experience
in paint removal projects; and

**(5)** Documentation of the individual's qualifications including
records of training and experience.

Perform work according to the accepted plan. If the measures fail to
perform as intended, immediately stop work and take corrective action.
Collect and properly dispose of all material including waste water that
is used in preparing, cleaning, or painting.

**563.04 Protection of the Work.** Protect adjacent surfaces that are
not to be painted by using tarps, screens, paper, cloth, or other
suitable means. Prevent contamination of freshly-painted surfaces by
dust, oil, grease, or other harmful or deleterious material.

**563.05 Surface Preparation, General.** Notify the CO in writing at
least 7 days before beginning operations. Immediately before painting,
prepare the surface according to the following:

**(a)** Clean the surface to the specified cleanliness level.

**(b)** Remove dirt, dust, and other contaminants from the surface using
methods recommended by the paint manufacturer.

**(c)** Thoroughly dry the surface.

**(d)** Determine that the surface temperature is between 50 and 100 ºF.

**(e)** Determine that the surface temperature is 5 ºF or more above the
dew point according to ASTM E 337.

**(f)** Determine that the humidity is 85 percent or less, unless
specified otherwise on the manufacturer\'s product data sheet.

Suitable engineering controls such as enclosures and dehumidification
may be used to provide the conditions required above.

**563.06 Paint Application, General.** Use safe handling practices that
conform to the manufacturer\'s safety data sheet and instructions. Mix
and apply paint according to the product instructions. Mix paint with
mechanical mixers for a sufficient length of time to thoroughly blend
the pigment and vehicle together. Continue the mixing during
application. Do not thin paint that is formulated ready for application.

Paint in a neat and workmanlike manner that does not produce excessive
paint build‑up, runs, sags, skips, holidays, or thin areas in the paint
film. Measure the wet film thickness during application and adjust the
application rate such that, after curing, the desired dry film thickness
is obtained. Apply paint by brush, spray, roller, or any combination
thereof if permitted by the manufacturer\'s product data sheet.

Use brushes that have sufficient bristle body and length to spread the
paint in a uniform film. Use round, oval shaped brushes, or flat brushes
no wider than 4½ inches. Evenly spread and thoroughly brush out the
paint as it is applied.

Use airless or conventional spray equipment with suitable traps,
filters, or separators to exclude oil and water from the compressed air.
Use compressed air that does not show black or wet spots when tested
according to ASTM D 4285. Use the spray gun tip sizes and pressures
recommended by the manufacturer.

Use rollers only on flat, even surfaces. Do not use rollers that leave a
stippled texture in the paint film.

Use sheepskin daubers, bottle brushes, or other acceptable methods to
paint surfaces that are inaccessible for painting by regular means.

Cure each coat of paint according to the manufacturer\'s
recommendations. Correct all thin areas, skips, holidays, and other
deficiencies before the next application of paint. Tint succeeding
applications of paint to contrast with the paint being covered. The CO
will approve the color for the finish coat before application.

Coat surfaces that will be inaccessible after erection with the full
number of undercoats required before erection. After erection,
thoroughly clean all areas where the undercoating is damaged or
deteriorated, and spot coat these with the specified undercoats to the
required thickness before applying the final coat.

**563.07 Structural Iron and Steel.**

**(a) Paint systems.**

**(1) New surfaces or surfaces with all existing paint removed.**
Furnish a paint system shown in Table 563-1.

**(2) Surfaces with existing sound paint.** Furnish a paint system
compatible with the existing paint. Furnish a system shown in Table
563-2 or a system approved for use on steel structures by the State
highway agency in the State in which the structure is located.

At least 14 days before ordering paint, verify compatibility of the
proposed system with the existing system as follows:

*(a)* Select a test area of at least 30 square feet in a condition
representative of the condition of the structure. Perform the specified
level of surface preparation, and apply the proposed system to the
existing topcoat and to the existing primer. Observe for lifting,
bleeding, blistering, wrinkling, cracking, flaking, or other evidence of
incompatibility.

*(b)* Verify that no indication of incompatibility exists at least 14
days after the application of each product. Perform adhesion tests
according to ASTM D 3359, method A. Notify the CO immediately if
adhesion testing fails at the interface of the existing system and
substrate or between the existing finish coat and primer. An adhesion
failure indicates incompatibility. Choose a more compatible paint
system.

**(b) Surface preparation.** Do not remove sound paint unless
specifically required by the contract.

**(1) New surfaces or surfaces with all existing paint removed.** Remove
all dirt, mill scale, rust, paint, and other foreign material from
exposed surfaces by blast cleaning to near white metal according to
SSPC-SP 10.

Use compressed air that is free from oil or moisture and does not show
black or wet spots when tested according to ASTM D 4285. Do not use
unwashed sand or abrasives that contain salts, dirt, oil, or other
foreign matter. Before blast cleaning near machinery, seal bearings,
journals, motors, and moving parts against entry of abrasive dust.

Blast clean with clean dry slag, mineral grit, steel shot, or steel
grit. Use a suitable gradation to produce a dense, uniform anchor
pattern. Produce an anchor profile height of 1 to 2 mils, but not less
than that recommended by the paint system manufacturer\'s product data
sheet. Measure anchor profile height using the tape method according to
ASTM D 4417.

+----------+---+---+--------+---------+--------+---------+-----+------+
| Table    | * | * | **Less | Low VOC | Low    | Low VOC | 6-9 | \    |
| 563-1    | * | * | Aggr   | alkyd   | VOC    | alkyd   | m   | (1\) |
|          | P | 5 | essive |         | alkyd  |         | ils | Sy   |
| St       | a | * | En     | 2-3     |        | 2-3     | dry | stem |
| ructural | i | * | vironm | mils    | 2-3    | mils    |     | 1,   |
| Iron and | n |   | ents** | dry     | mils   | dry     |     | 2,   |
| Steel    | t |   |        |         | dry    |         |     | or 3 |
| Coating  | S |   | **(No  |         |        |         |     | is   |
| Systems  | y |   | S      |         |        |         |     | for  |
| for      | s |   | alt)** |         |        |         |     | the  |
|          | t |   |        |         |        |         |     | c    |
| New      | e |   |        |         |        |         |     | orro |
| Surfaces | m |   |        |         |        |         |     | sion |
| and      | ^ |   |        |         |        |         |     | pr   |
| Surfaces | ( |   |        |         |        |         |     | otec |
| with All | 1 |   |        |         |        |         |     | tion |
| Existing | ) |   |        |         |        |         |     | of   |
| Paint    | ^ |   |        |         |        |         |     | iron |
| Removed  | * |   |        |         |        |         |     | and  |
|          | * |   |        |         |        |         |     | s    |
|          |   |   |        |         |        |         |     | teel |
|          |   |   |        |         |        |         |     | in   |
|          |   |   |        |         |        |         |     | aggr |
|          |   |   |        |         |        |         |     | essi |
|          |   |   |        |         |        |         |     | vely |
|          |   |   |        |         |        |         |     | c    |
|          |   |   |        |         |        |         |     | orro |
|          |   |   |        |         |        |         |     | sive |
|          |   |   |        |         |        |         |     | atm  |
|          |   |   |        |         |        |         |     | osph |
|          |   |   |        |         |        |         |     | eric |
|          |   |   |        |         |        |         |     | envi |
|          |   |   |        |         |        |         |     | ronm |
|          |   |   |        |         |        |         |     | ents |
|          |   |   |        |         |        |         |     | such |
|          |   |   |        |         |        |         |     | as   |
|          |   |   |        |         |        |         |     | mar  |
|          |   |   |        |         |        |         |     | ine, |
|          |   |   |        |         |        |         |     | ind  |
|          |   |   |        |         |        |         |     | ustr |
|          |   |   |        |         |        |         |     | ial, |
|          |   |   |        |         |        |         |     | high |
|          |   |   |        |         |        |         |     | h    |
|          |   |   |        |         |        |         |     | umid |
|          |   |   |        |         |        |         |     | ity, |
|          |   |   |        |         |        |         |     | or   |
|          |   |   |        |         |        |         |     | st   |
|          |   |   |        |         |        |         |     | ruct |
|          |   |   |        |         |        |         |     | ures |
|          |   |   |        |         |        |         |     | exp  |
|          |   |   |        |         |        |         |     | osed |
|          |   |   |        |         |        |         |     | to   |
|          |   |   |        |         |        |         |     | dei  |
|          |   |   |        |         |        |         |     | cing |
|          |   |   |        |         |        |         |     | sa   |
|          |   |   |        |         |        |         |     | lts. |
|          |   |   |        |         |        |         |     | Sy   |
|          |   |   |        |         |        |         |     | stem |
|          |   |   |        |         |        |         |     | 4 or |
|          |   |   |        |         |        |         |     | 5 is |
|          |   |   |        |         |        |         |     | for  |
|          |   |   |        |         |        |         |     | use  |
|          |   |   |        |         |        |         |     | in   |
|          |   |   |        |         |        |         |     | t    |
|          |   |   |        |         |        |         |     | hose |
|          |   |   |        |         |        |         |     | envi |
|          |   |   |        |         |        |         |     | ronm |
|          |   |   |        |         |        |         |     | ents |
|          |   |   |        |         |        |         |     | free |
|          |   |   |        |         |        |         |     | from |
|          |   |   |        |         |        |         |     | high |
|          |   |   |        |         |        |         |     | co   |
|          |   |   |        |         |        |         |     | ncen |
|          |   |   |        |         |        |         |     | trat |
|          |   |   |        |         |        |         |     | ions |
|          |   |   |        |         |        |         |     | of   |
|          |   |   |        |         |        |         |     | s    |
|          |   |   |        |         |        |         |     | alts |
|          |   |   |        |         |        |         |     | or   |
|          |   |   |        |         |        |         |     | po   |
|          |   |   |        |         |        |         |     | llut |
|          |   |   |        |         |        |         |     | ants |
|          |   |   |        |         |        |         |     | that |
|          |   |   |        |         |        |         |     | c    |
|          |   |   |        |         |        |         |     | ause |
|          |   |   |        |         |        |         |     | ag   |
|          |   |   |        |         |        |         |     | gres |
|          |   |   |        |         |        |         |     | sive |
|          |   |   |        |         |        |         |     | c    |
|          |   |   |        |         |        |         |     | orro |
|          |   |   |        |         |        |         |     | sion |
|          |   |   |        |         |        |         |     | e    |
|          |   |   |        |         |        |         |     | nvir |
|          |   |   |        |         |        |         |     | onme |
|          |   |   |        |         |        |         |     | nts. |
+----------+---+---+--------+---------+--------+---------+-----+------+
|          |   | * | **Less | Acrylic | A      | Acrylic | 6-9 |      |
|          |   | * | Aggr   | latex   | crylic | latex   | m   |      |
|          |   | 4 | essive |         | latex  |         | ils |      |
|          |   | * | En     | 2-3     |        | 2-3     | dry |      |
|          |   | * | vironm | mils    | 2-3    | mils    |     |      |
|          |   |   | ents** | dry     | mils   | dry     |     |      |
|          |   |   |        |         | dry    |         |     |      |
|          |   |   | **(No  |         |        |         |     |      |
|          |   |   | S      |         |        |         |     |      |
|          |   |   | alt)** |         |        |         |     |      |
+----------+---+---+--------+---------+--------+---------+-----+------+
|          |   | * | **Aggr | Moistur | Mo     | Moistur | 6-9 |      |
|          |   | * | essive | e-cured | isture | e-cured | m   |      |
|          |   | 3 | En     | u       | -cured | u       | ils |      |
|          |   | * | vironm | rethane | ur     | rethane | dry |      |
|          |   | * | ents** |         | ethane |         |     |      |
|          |   |   |        | 2-3     |        | 2-3     |     |      |
|          |   |   | **(S   | mils    | 2-3    | mils    |     |      |
|          |   |   | alt)** | dry     | mils   | dry     |     |      |
|          |   |   |        |         | dry    |         |     |      |
+----------+---+---+--------+---------+--------+---------+-----+------+
|          |   | * | **Aggr | Zi      | Epoxy  | Al      | 8   |      |
|          |   | * | essive | nc-rich |        | iphatic | -11 |      |
|          |   | 2 | En     | epoxy   | 3-4    | u       | m   |      |
|          |   | * | vironm |         | mils   | rethane | ils |      |
|          |   | * | ents** | 3-4     | dry    |         | dry |      |
|          |   |   |        | mils    |        | 2-3     |     |      |
|          |   |   | **(S   | dry     |        | mils    |     |      |
|          |   |   | alt)** |         |        | dry     |     |      |
+----------+---+---+--------+---------+--------+---------+-----+------+
|          |   | * | **Aggr | In      | Epoxy  | Al      | 8   |      |
|          |   | * | essive | organic |        | iphatic | -11 |      |
|          |   | 1 | En     | zinc    | 2-3    | u       | m   |      |
|          |   | * | vironm | type I  | mils   | rethane | ils |      |
|          |   | * | ents** | 3-4     | dry    |         | dry |      |
|          |   |   |        | mils    |        | 2-3     |     |      |
|          |   |   | **(S   | dry     |        | mils    |     |      |
|          |   |   | alt)** |         |        | dry     |     |      |
+----------+---+---+--------+---------+--------+---------+-----+------+
|          | * |   |        | **P     | **In   | **Top** | *   |      |
|          | * |   |        | rimer** | termed |         | *To |      |
|          | C |   |        |         | iate** |         | tal |      |
|          | o |   |        |         |        |         | Th  |      |
|          | a |   |        |         |        |         | ick |      |
|          | t |   |        |         |        |         | nes |      |
|          | * |   |        |         |        |         | s** |      |
|          | * |   |        |         |        |         |     |      |
+----------+---+---+--------+---------+--------+---------+-----+------+

Table 563 - 2

Structural Iron and Steel Coating Systems for

Surfaces with Existing Sound Paint

+-------------+----------------+-------------------+-------------------+
| **Coat**    | **Paint System |                   |                   |
|             | ^(1)^**        |                   |                   |
+-------------+----------------+-------------------+-------------------+
|             | **6**          | **7**             | **8**             |
+-------------+----------------+-------------------+-------------------+
|             | **Aggressive** | **Less            | **Less            |
|             |                | Aggressive**      | Aggressive**      |
|             | **             |                   |                   |
|             | Environments** | **Environments**  | **Environments**  |
|             |                |                   |                   |
|             | **(Salt)**     | **(No Salt)**     | **(No Salt)**     |
+-------------+----------------+-------------------+-------------------+
| **Primer**  | Moisture-cured | Low VOC alkyd     | Low viscosity     |
|             |                |                   |                   |
|             | urethane       | 2-3 mils dry      | epoxy sealer      |
|             |                |                   |                   |
|             | 2-3 mils dry   |                   | 1-2 mils dry      |
+-------------+----------------+-------------------+-------------------+
| **Int       | Moisture-cured | Low VOC alkyd     | Epoxy             |
| ermediate** |                |                   |                   |
|             | urethane       | 2-3 mils dry      | 3-4 mils dry      |
|             |                |                   |                   |
|             | 2-3 mils dry   |                   |                   |
+-------------+----------------+-------------------+-------------------+
| **Top**     | Moisture-cured | Low VOC           | Aliphatic         |
|             |                |                   |                   |
|             | urethane or    | silicone-alkyd    | urethane          |
|             |                |                   |                   |
|             | aliphatic      | 2-3 mils dry      | 2-3 mils dry      |
|             | urethane       |                   |                   |
|             |                |                   |                   |
|             | 2-3 mils dry   |                   |                   |
+-------------+----------------+-------------------+-------------------+
| **Total     | 6-9 mils dry   | 6-9 mils dry      | 6-9 mils dry      |
| Thickness** |                |                   |                   |
+-------------+----------------+-------------------+-------------------+

\(1\) System 6 is for the corrosion protection of iron and steel in
aggressively corrosive atmospheric environments such as marine,
industrial, high humidity, or structures exposed to deicing salts.
System 7 or 8 is for use in those environments free from high
concentrations of salts or pollutants that cause aggressive corrosion
environments.

The same day cleaning is performed, remove dirt, dust, and other debris
from the surface by brushing, blowing with clean dry air, or vacuuming
and apply the first coat of paint to the blast cleaned surfaces. If the
cleaned surfaces rust or become contaminated before painting, repeat the
blast cleaning.

**(2) Surfaces with existing sound paint.** Wash all areas to be painted
with pressurized water to remove dirt, surface chalking, loose rust, and
contaminants such as chlorides. Maintain a wash water pressure of at
least 500 pounds per square inch. Capture all wash water and removed
waste according to appropriate regulations.

Clean according to SSPC-SP 2 --- Hand Tool Cleaning, SSPC-SP 3 --- Power
Tool Cleaning, or SSPC-SP 6 --- Commercial Blast Cleaning to remove
dirt, loose mill scale, loose rust, or paint that is not firmly bonded
to the underlying surface. Clean small areas that show pinhole
corrosion, stone damage from traffic, or minor scratches. Clean at least
2 inches beyond the damaged areas. Feather edges of remaining old paint
to achieve a reasonably smooth surface.

The same day hand- or power-tool cleaning is performed, remove dirt,
dust, and other contaminants from the surface with solvent-cleaning
methods according to SSPC-SP 1, and spot paint all bare steel areas with
the first coat of paint. If the cleaned surfaces rust or become
contaminated before painting, repeat solvent cleaning. Repair all damage
to sound paint by applying the entire system.

> **(c) Application of paints.** Apply each coat to the wet film
> thickness as recommended by the paint manufacturer to obtain the
> specified dry film thickness. Verify the application rate of each coat
> with a wet film paint thickness gauge immediately after applying paint
> to the surface. Confirm the application rate by measuring the dry film
> thickness after the solvent has evaporated from the surface.

**563.08 Painting Galvanized Surfaces.** Remove all oil, grease, or
other contaminants on the surface by washing with a mineral spirit
solvent according to SSPC-SP 1.

Apply the coating system shown in Table 563-3 for other metals.

Table 563-3

Coating Systems for Other Structures

+----------+--------------+--------------+---------------+-----------+
| **Sub    | **Paint      |              |               |           |
| strate** | Coatings**   |              |               |           |
+----------+--------------+--------------+---------------+-----------+
|          | **Primer**   | **In         | **Finish**    | **Total** |
|          |              | termediate** |               |           |
+----------+--------------+--------------+---------------+-----------+
| **Smooth | Exterior     | Exterior     | Exterior      | 5-7 mils  |
| Wood**   | wood primer  | latex        | latex         |           |
|          | ^(1)^        |              |               | dry       |
|          |              | or alkyd     | or alkyd      |           |
|          | 2-3 mils dry |              |               |           |
|          |              | 1-2 mils dry | 1-2 mils dry  |           |
+----------+--------------+--------------+---------------+-----------+
| **Rough  | Exterior     | Exterior     | Exterior      | 3-6 mils  |
| Lumber** | latex        | latex        | latex         |           |
|          |              |              |               | dry       |
|          | or alkyd     | or alkyd     | or alkyd      |           |
|          | ^(1)^        |              |               |           |
|          |              | 1-2 mils dry | 1-2 mils dry  |           |
|          | 1-2 mils dry |              |               |           |
+----------+--------------+--------------+---------------+-----------+
| **Co     | Epoxy single |              |               | 3-6 mils  |
| ncrete** | coat 3-4     |              |               |           |
|          | mils dry.    |              |               | dry       |
|          | For gloss    |              |               |           |
|          | finish,      |              |               |           |
|          |              |              |               |           |
|          | finish with  |              |               |           |
|          | aliphatic-   |              |               |           |
|          | polyurethane |              |               |           |
|          | (2 mils      |              |               |           |
|          | dry).        |              |               |           |
+----------+--------------+--------------+---------------+-----------+
| *        | Masonry      | Exterior     | Exterior      | 5-7 mils  |
| *Masonry | block filler | latex        | latex         |           |
| Block**  |              |              |               | dry       |
|          | 2-3 mils dry | or alkyd     | or alkyd      |           |
|          |              |              |               |           |
|          |              | 1-2 mils dry | 1-2 mils dry  |           |
+----------+--------------+--------------+---------------+-----------+
| **Al     | Metal primer | Exterior     | Exterior      | 4-6 mils  |
| uminum** |              | latex        | latex         |           |
|          | 1-2 mils dry |              |               | dry       |
|          |              | or alkyd     | or alkyd      |           |
|          |              |              |               |           |
|          |              | 1-2 mils dry | 1-2 mils dry  |           |
+----------+--------------+--------------+---------------+-----------+
| **Other  | Metal primer | Exterior     | Exterior      | 4-6 mils  |
| Metals** | ^(2)^        | latex        | latex         |           |
|          |              |              |               | dry       |
|          | 1-2 mils dry | or alkyd     | or alkyd      |           |
|          |              |              |               |           |
|          |              | 1-2 mils dry | 1-2 mils dry  |           |
+----------+--------------+--------------+---------------+-----------+

\(1\) For untreated wood, thin the primer with up to 0.1 gallon of
turpentine and 0.1 gallon of linseed oil per gallon of paint.

\(2\) For galvanized surfaces, use an epoxy primer (1-2 mils dry
thickness) or a vinyl wash primer (1 mil dry thickness).

**563.09 Painting Timber Structures.** Dry timber to a moisture content
of 20 percent or less. On previously painted timber, remove all cracked
or peeled paint, loose chalky paint, dirt, and other foreign material by
wire brushing, scraping, or other approved methods. On timber treated
with creosote or oilborne pentachlorophenol preservative, wash and brush
away visible salt crystals on the wood surface and allow to dry. Remove
all dust or other foreign material from the surface to be painted.

Apply the coating system shown in Table 563-3. The primer may be applied
before erection. After the primer dries and the timber is in place, fill
all cracks, checks, nail holes, or other depressions flush with the
surface using approved putty. Evenly spread and thoroughly work the
paint into all corners and recesses. Allow the full thickness of the
applied coat of paint to dry before applying the next coat.

**563.10 Painting Concrete Structures.** Remove all laitance, dust,
foreign material, curing compound, form oil, grease or other deleterious
material from the concrete surface. Remove form oil, grease, or curing
compound by washing with a 5 percent solution of trisodium phosphate and
rinsing with clean water. Allow the surface to dry completely.

Give the cleaned surface a light abrasive sweep to remove mortar wash or
other contaminants. Remove all residue and dust by hand, broom,
compressed air or other approved methods.

Apply the coating system coatings shown in Table 563-3. Evenly spread
and thoroughly work the paint into all corners and recesses. Allow the
full thickness of the applied coat of paint to dry before applying the
next coat.

**563.11 Acceptance.** Paint material will be evaluated under
Subsections 106.02 and 106.03. If sampling and testing of paint
components is required, sampling will be according to FSS 141 method
1021 and the testing of the paint properties will be according to the
procedures and methods listed in FSS 141.

Painting application will be evaluated under Subsection 106.02 and
106.04. The dry paint thickness on steel structures will be determined
using a type I magnetic film thickness gauge according to SSPC-PA 2 or
by using destructive methods according to ASTM D 4138. If destructive
methods are used, repair test locations in an approved manner.

Measurement

**563.12** Measure the Section 563 items listed in the bid schedule
according to Subsection 109.02.

Payment

**563.13** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 563 pay items listed in the bid
schedule. Payment will be full compensation for the work prescribed in
this Section. See Subsection 109.05.

## Section 564. --- BEARING DEVICES

Description

**564.01** This work consists of furnishing and installing bridge
bearings.

Bearing devices are designated as elastomeric, rocker, roller, sliding
plate, pot, spherical and disk bearings.

Material

**564.02** Conform to the following Subsections:

Elastomeric bearing pads 717.10

Galvanized coatings 717.07

Non-shrink grout 725.22(c)

Tetrafluoroethylene (TFE) surfaces for bearings 717.11

Construction Requirements

**564.03 General.**

**(a) Drawings.** Prepare and submit drawings for the bearings according
to Subsection 104.03 and Section 18 of the AASHTO *Standard
Specifications for Highway Bridges* Division II, Volume II. Show all
details of the bearings including the material proposed for use. Obtain
approval before beginning fabrication.

**(b) Fabrication.** Fabricate bearings according to Section 18 of the
AASHTO *Standard Specifications for Highway Bridges* Division II, Volume
II. The surface finish of bearing components in contact with each other
or with concrete, but not embedded in concrete, shall conform to
Subsection 555.08(e).

Preassemble bearing assemblies in the shop and check for proper
completeness and geometry. Galvanize steel bearing components and anchor
bolts. Do not galvanize stainless steel bearing components or anchor
bolts.

**(c) Packaging, handling, and storage.** Before shipping from the
manufacturer, clearly identify each bearing component and mark on its
top the location and orientation in the structure. Securely bolt, strap,
or otherwise fasten the bearings to prevent any relative movement.

Package bearings so they are protected from damage due to shipping,
handling, weather, or other hazards. Do not dismantle bearing assemblies
at the site except for inspection or installation.

Store all bearing devices and components at the work site in a location
that provides protection from environmental and physical damage.

**(d) Construction and installation.** Clean the bearings of all
deleterious substances. Install the bearings to the positions shown on
the drawings. Set bearings and bearing components to the dimensions
shown on the drawings or as prescribed by the manufacturer. Adjust
according to the manufacturer\'s instructions to compensate for
installation temperature and future movements of the bridge.

Set bridge bearings level at the exact elevation and position. Provide
full and even bearing on all external bearing contact surfaces. If
bearing surfaces are at improper elevations, not level, or if bearings
cannot otherwise be set properly, notify the CO and submit a written
proposal to modify the installation for approval.

Bed metallic bearing assemblies, not embedded in concrete, on concrete
with an approved filler or fabric material.

Set elastomeric bearing pads directly on properly prepared concrete
surfaces without bedding material.

Machine bearing surfaces seated directly on steel to provide a level and
planar surface upon which to place the bearing.

**564.04 Elastomeric Bearings.** The bearings include nonreinforced pads
(consisting of elastomer only) and reinforced bearings with steel or
fabric laminates.

Reinforce elastomeric bearings more than 1/2 inch thick with laminates
every 1/2 inch through the entire thickness.

Fabricate elastomeric bearings according to AASHTO M 251. Use material
that meets the flash tolerance, finish, and appearance requirements of
the *Rubber Handbook* as published by the Rubber Manufacturer\'s
Association Incorporated, RMA F3 and T.063 for molded bearings and RMA
F2 for extruded bearings. Determine compliance with AASHTO M 251, level
I acceptance criteria.

Mark each reinforced bearing with indelible ink or flexible paint. The
marking information shall include the order number, lot number, bearing
identification number, and elastomer type and grade number. Unless
otherwise specified, mark on a face that is visible after erection of
the bridge. Furnish a list of all individual bearing numbers.

Place bearings on a level surface. Correct any misalignment in the
support to form a level surface. Do not weld steel girders or base
plates to the exterior plates of the bearing unless there is more than
1½ inches of steel between the weld and elastomer. Do not expose the
elastomer or elastomer bond to instantaneous temperatures greater than
400 ºF.

**564.05 Rocker, Roller, and Sliding Bearings.** When TFE coatings are
required, use coatings conforming to Subsection 564.07.

Fabricate rocker, roller, and sliding bearings according to the details
shown on the plans and to Section 555. Perform fabrication according to
the standard practice in modern commercial shops. Remove burrs, rough
and sharp edges, and other flaws. Stress relieve rocker, roller, and
other bearings that are built up by welding sections of plate together
before boring, straightening, or finished machining.

Thoroughly coat all contact surfaces with oil and graphite just before
placing roller bearings. Install rocker, roller, and sliding bearings so
they are vertical at the specified mean temperature after release of
falsework and after any shortening due to prestressing forces. Take into
account any variation from mean temperature of the supported span at
time of installation and any other anticipated changes in length of the
supported span.

Make sure the superstructure has full and free movement at movable
bearings. Carefully position cylindrical bearings so that their axes of
rotation align and coincide with the axis of rotation of the
superstructure.

**564.06 Masonry, Sole, and Shim Plates for Bearings.** Provide metal
plates used in masonry, sole, and shim plates, conforming to AASHTO
M 270, grade 36.

Fabricate and finish steel according to Section 555. Form holes in
bearing plates by drilling, punching, or accurately controlled oxygen
cutting. Remove all burrs by grinding.

Accurately set bearing plates in level position as shown on the drawings
and provide a uniform bearing over the bearing contact area. When plates
are embedded in concrete, make provision to keep them in correct
position as the concrete is placed.

**564.07 Tetrafluoroethylene (TFE) Surfaces for Bearings.** Furnish TFE
material that is factory-bonded, mechanically connected, or recessed
into the backup material as shown on the plans.

Bond or mechanically attach the fabric containing TFE fibers to a rigid
substrate. Use a fabric capable of carrying unit loads of 10,000 pounds
per square inch without cold flow. Use a fabric‑substrate bond capable
of withstanding, without delamination, a shear force equal to 10 percent
of the perpendicular or normal application loading plus any other
bearing shear forces.

Determine compliance using approved test methods and procedures
according to Section 18, Subsection 18.8.3, AASHTO *Standard
Specifications for Highway Bridges* Division II, Volume II. If the test
facility does not permit testing completed bearings, manufacture extra
bearings and prepare samples of at least 100-kip capacity at normal
working stresses.

Determine static and dynamic coefficient of friction at first movement
of the test bearing at a sliding speed of less than 1 inch per minute.
The coefficient of friction shall not exceed the coefficient of friction
as specified in Table 564-1 or by the manufacturer.

Furnish a listing of all individual bearing numbers.

Table 564-1

Coefficient of Friction

+---------------------------------+---------------------+--------------+
| **Material**                    | **Bearing           | **Friction** |
|                                 | Pressure**          |              |
|                                 |                     | **C          |
|                                 | **(pounds per**     | oefficient** |
|                                 |                     |              |
|                                 | **square inch)**    |              |
+---------------------------------+---------------------+--------------+
| Unfilled TFE, fabric containing | 500                 | 0.08         |
| TFE fibers, or TFE-perforated   |                     |              |
| metal composite                 |                     |              |
+---------------------------------+---------------------+--------------+
|                                 | 2,000               | 0.06         |
+---------------------------------+---------------------+--------------+
|                                 | 3,500               | 0.04         |
+---------------------------------+---------------------+--------------+
| Filled TFE                      | 500                 | 0.12         |
+---------------------------------+---------------------+--------------+
|                                 | 2,000               | 0.10         |
+---------------------------------+---------------------+--------------+
|                                 | 3,500               | 0.08         |
+---------------------------------+---------------------+--------------+
| Interlocked bronze and filled   | 500                 | 0.10         |
| TFE structures                  |                     |              |
+---------------------------------+---------------------+--------------+
|                                 | 2,000               | 0.07         |
+---------------------------------+---------------------+--------------+
|                                 | 3,500               | 0.05         |
+---------------------------------+---------------------+--------------+

**564.08 Anchor Bolts.** Furnish swedge or thread anchor bolts
conforming to ASTM A 307 or as shown on the plans or specified in the
contract.

Preset anchor bolts before placement of the concrete or install anchor
bolts in drilled holes after placement of the concrete. If installed
after concrete placement, secure the bolts in the drilled holes with
non-shrink cement grout or an approved chemical adhesive. If non‑shrink
cement grout is used, drill holes 1 inch in diameter greater than the
bolt. If chemical adhesives are used, follow adhesive manufacturer's
recommendations for hole-diameter.

Adjust bolt locations for superstructure temperature as required. Do not
restrict free movement of the superstructure at movable bearings by
anchor bolts or nuts.

**564.09 Bedding of Masonry Plates.** Place filler or fabric as bedding
material under masonry plates if required by the contract. Use the type
of filler or fabric specified and install to provide full bearing on
contact areas. Thoroughly clean the contact surfaces of the concrete and
steel immediately before placing the bedding material and installing
bearings or masonry plates. If bedding materials are not specified,
comply with AASHTO 18.4.10 as directed by the CO.

**564.10 Acceptance.** Bearing devices will be evaluated under
Subsections 106.02 and 106.03. Furnish a production certification with
each shipment of bearing devices.

Bearing device installation will be evaluated under Subsections 106.02
and 106.04.

Measurement

**564.11** Measure the Section 564 items listed in the bid schedule
according to Subsection 109.02.

Payment

**564.12** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 564 pay item listed in the bid
schedule. Payment will be full compensation for the work prescribed in
this Section. See Subsection 109.05.

## Section 565. --- DRILLED SHAFTS

Description

**565.01** This work consists of constructing drilled shafts.

Material

**565.02** Conform to the following Section and Subsections:

Casings 717.01(a)

Neat cement grout 725.22(f)

Mineral slurry 725.26

Reinforcing steel 709.01

Structural concrete 552

Construction Requirements

**565.03 Qualifications and Submittals.** Submit the following for
acceptance at least 30 days before constructing drilled shafts.
Acceptance of the Contractor's personnel, installation plan, and trial
shafts does not relieve the Contractor of the responsibility for
obtaining the required results in the completed work.

**(a) Personnel**

**(1) Construction personnel.** Use personnel with at least 3 years
experience in the construction of drilled shafts. Provide resumes of job
experience, project description, the owning agency's name and current
phone number, and the Contractor's name and current phone number that
the individual worked for while constructing the drilled shafts.

**(2) Testing personnel.** Use an engineer with at least two years
experience with the nondestructive crosshole sonic logging method for
concrete drilled shafts to perform field-testing and interpretation of
the recorded measurements. Provide a resume of job experience, project
description, owning agency's name and current phone number. Provide
experienced labor support as needed to adequately perform the required
tests.

**(b) Installation Plan.** Furnish the following:

**(1)** A description, including capacities, of the proposed equipment
to be used including cranes, drills, drilling unit, augers, bailing
buckets, and final cleaning equipment. Include an explanation of why the
equipment was selected and a description of the equipment's suitability
to the anticipated site and subsurface conditions. Include a project
history of the drilling equipment that demonstrates its successful use
on shafts of equal or greater size in similar subsurface conditions.

**(2)** Demonstrate an understanding of the subsurface conditions at the
site. Reference the available subsurface data provided in the contract
test hole boring logs and in the geotechnical report prepared for this
project.

**(3)** Details of overall construction operation sequence and the
sequence of shaft construction in bents or groups.

**(4)** Details of shaft excavation methods including proposed drilling
methods; methods for removing materials from the shafts; procedures for
maintaining correct horizontal and vertical alignment of the excavation;
and a disposal plan for excavated material.

**(5)** When a mineral slurry is required, details of the methods to
mix, circulate, use, maintain, and dispose of the slurry. Provide a
detailed slurry mix design and discuss its suitability to the subsurface
conditions.

**(6)** Details of methods used to ensure shaft stability during
excavation and concrete placement. Include a review of the method's
suitability to the anticipated site and subsurface conditions. If
casings are proposed or required, provide casing dimensions and detailed
procedures for permanent casing installation and temporary casing
installation and removal.

**(7)** Details of reinforcement placement including bracing, centering,
centralizers, and lifting and support methods.

**(8)** Details of concrete placement including proposed operational
procedures for free fall, tremie, or pumping methods.

**(9)** The method used to form an emergency horizontal construction
joint during concrete placement.

**565.04 Trial Drilled Shafts.** When trial drilled shafts are required
by the contract, perform the work according to the applicable
requirements of Subsection 565.05 and the following.

Before drilling holes for production shafts, demonstrate that the
proposed methods and equipment are adequate by drilling a trial drilled
shaft adjacent to the production shafts at an approved location. Make
the center-to-center spacing between the trial shaft and production
shafts at least 3 shaft diameters or 2 bell diameters whichever is
larger.

Construct the trial drilled shaft to the same size and to the tip
elevation of the deepest production shaft shown on the plans. When bells
are specified for production shafts, include a bell in the final shaft
to verify the feasibility of belling in the specified bearing stratum.

If material caves into the drilled hole or the hole deforms excessively,
case the hole. When casings are used, seat the casing as necessary to
prevent caving and to allow dewatering of the hole. Remove all material
inside the hole. Keep the casing in place a minimum of 4 hours while
attempting to remove all water in the hole. Record the rate of
groundwater seepage into the hole. After this 4 hour period, fill the
hole with saturated sand while the casing is removed to simulate the
concreting operation and casing removal for the production drilled
shafts. Concrete or reinforcing steel is not required in the trial
drilled shaft.

If the trial drilled shaft is determined to be unsatisfactory, modify
the methods and equipment. Submit a new installation plan and drill a
new trial drilled shaft at the Contractors\' expense.

Once approval is given to construct the production drilled shafts, no
changes are permitted in the installation plan without prior approval.

**565.05 Drilled Shafts.**

**(a) Excavation.** Do not excavate additional shafts, allow excessive
wheel loads, or allow excessive vibrations within 15 feet or 3 shaft
diameters, whichever is greater, of a newly constructed shaft for at
least 20 hours. Excavate for structure footings supported on drilled
shafts and construct fills before drilling. Position the drilled shaft
within 3 inches of the required position in a horizontal plane at the
top of shaft elevation.

Excavate holes according to the accepted installation plan. Do not allow
the alignment of a vertical shaft to vary from the required alignment by
more than 1/4 inch per foot of depth. Do not allow the alignment of a
battered shaft to vary by more than 1/2 inch per foot of depth from the
required batter alignment.

Provide equipment with the capability to excavate shafts 20 percent
longer than and the same diameter as those shown on the plans.

Maintain a log of material excavated from the drilled shaft that
includes the following information:

• Description and approximate top and bottom elevation of each type of
soil or rock material encountered and the date and time the soil or rock
material was encountered.

• Elevation and approximate rate of any seepage or groundwater
encountered.

• Equipment used, time required to drill shaft, bit changes, breakdowns,
and all other difficulties encountered.

• Remarks.

When it is determined that the hole sidewall has softened due to
excavation methods, swelled due to delays in concreting, or degraded
because of slurry cake buildup, overream sidewall a minimum of 1/2 inch
or a maximum of 3 inches to sound material.

At the time of concrete placement, clean the hole so no more than 50
percent of the bottom of each hole has more than 1/2 inch of sediment
and the maximum depth of sediment at any place on the bottom of the hole
does not exceed 1½ inches. For dry holes, reduce the depth of water to 3
inches or less before placing concrete.

**(1) Dry method.** Use the dry construction method at sites where the
groundwater level and soil conditions are suitable to permit
construction of the shaft in a relatively dry excavation and where the
sides and bottom of the shaft may be visually inspected before placing
concrete. The dry method consists of drilling the shaft, removing
accumulated water, removing loose material from the excavation, placing
the reinforcing cage, and concreting the shaft in a relatively dry
excavation.

The dry construction method can only be used when the trial shaft
excavation demonstrates all the following:

*(a)* Less than 12 inches of water accumulates above the base of the
hole during a 1-hour period when no pumping is permitted;

*(b)* The sides and bottom of the hole remain stable without detrimental
caving, sloughing, or swelling over a 4-hour period immediately
following completion of excavation; and

*(c)* Loose material and water can be satisfactorily removed before
inspection and before concrete placement.

**(2) Wet method.** Use the wet construction method or the casing
construction method for shafts that do not meet the above requirements
for the dry construction method. This method consists of using water or
mineral slurry to maintain stability of the hole perimeter while
advancing the excavation to final depth, placing the reinforcing cage,
and concreting the shaft.

The wet method involves the following work:

*(a)* Desanding and cleaning the slurry;

*(b)* Final cleaning of the excavation using a bailing bucket, air lift,
submersible pump, or other approved devices;

*(c)* Placing the shaft concrete with a tremie or concrete pump
beginning at the shaft bottom;

*(d)* Providing, as needed, temporary surface casings to aid shaft
alignment and positioning; and

*(e)* Providing temporary surface casings to prevent sloughing of the
top of the shaft excavation unless it can be satisfactorily demonstrated
that the surface casing is not required.

Where drilled shafts are located in open water areas, extend exterior
casings from above the water elevation into the ground to protect the
shaft concrete from water action during placement and curing of the
concrete. Install the exterior casing in a manner that will produce a
positive seal at the bottom of the casing to prevent piping of water or
entry of other material from the shaft excavation.

**(b) Mineral slurry**. Premix the mineral slurry with clean fresh water
according to the mineral manufacturer's instructions to allow for
hydration before introduction into the shaft excavation. Use slurry
tanks of adequate capacity for slurry circulation, storage, and
treatment. Do not use excavated slurry pits or the shaft excavation to
mix the slurry. Do not add mineral component directly into the shaft
excavation.

Provide desanding equipment to limit slurry sand content to less than 4
percent by volume at any point in bore hole. Desanding is not required
for setting temporary casings, sign posts, or lighting mast foundations.

During drilling, maintain slurry surface in the shaft at least 4 feet
above the highest expected adjacent piezometric water pressure head and
at a level sufficient to prevent caving of the hole.

When there is a sudden significant loss of slurry from the hole, stop
drilling and take corrective measures to prevent slurry loss. Prevent
the slurry from setting up in the shaft. If at any time the slurry
construction method fails to produce the desired final results,
discontinue and use an approved alternative method.

Maintain density, viscosity, and pH of the mineral slurry during shaft
excavation and until concrete placement within the acceptable ranges
shown in Table 565-1. Take slurry samples using an approved sampling
tool. Extract slurry samples from the base of the shaft and 10 feet up
from the base of the shaft. Perform 4 sets of tests during first 8 hours
of slurry use. When results are acceptable and consistent, the testing
frequency may be decreased to one test set for every 4 hours of slurry
use.

Table 565-1

Acceptable Range of Values for Mineral Slurry

+-----------------------+-------------+-------------+-----------------+
| **Property**          | **At Time   | **In Hole   | **Method**      |
|                       | of**        | at**        |                 |
|                       |             |             |                 |
|                       | **Slurry    | **Time of   |                 |
|                       | Int         | Test**      |                 |
|                       | roduction** |             |                 |
|                       |             | **C         |                 |
|                       |             | oncreting** |                 |
+-----------------------+-------------+-------------+-----------------+
| **Density, pounds per | 64.3 --     | 64.3 --     | Density balance |
| cubic foot**          | 69.1        | 75.0        |                 |
+-----------------------+-------------+-------------+-----------------+
| **Viscosity, seconds  | 28 -- 45    | 28 -- 45    | Marsh cone      |
| per quart**           |             |             |                 |
+-----------------------+-------------+-------------+-----------------+
| **pH**                | 8 -- 11     | 8 -- 11     | pH paper or     |
|                       |             |             | meter           |
+-----------------------+-------------+-------------+-----------------+

**Note:** Density values shown are for fresh water. Increase density
values 2 pounds per cubic foot for saltwater. Perform tests when slurry
temperature is above 40 F. If desanding is required, sand content shall
not exceed 4 percent by volume at any point in the bore hole according
to the American Petroleum Institute sand content test.

When a slurry sample is unacceptable, make necessary corrections to
bring the slurry within specifications. Do not place concrete until the
results of the resampling and retesting indicate acceptable values.

Dispose of slurry in an environmentally acceptable manner at an approved
location.

**(c) Casings.** Use smooth, clean, watertight, steel casings of
sufficient strength to withstand handling and installation stresses and
the concrete and surrounding earth pressures. All casing diameters shown
on the plans are outside diameters.

The diameter of a permanent casing is subject to American Pipe Institute
tolerances applicable to regular steel pipe. Make the outside diameter
of the casing no less than the specified size of the shaft.

Install casings to produce a positive seal at the bottom that prevents
piping of water or other material into or out of the hole. If it becomes
necessary to remove a casing and substitute a longer or larger diameter
casing through caving soils, stabilize the excavation with slurry or
backfill before the new casing is installed. Other approved methods may
be used to control the stability of the excavation and protect the
integrity of the foundation soils.

All subsurface casings are to be considered temporary unless designated
in the contract as permanent casing. Remove temporary casing before
completing placement of concrete in any shaft excavation requiring
casing. During casing extraction, maintain a level of fresh concrete in
the casing that is a minimum of 5 feet above the surrounding level of
water or drilling fluid. Exercise care during casing removal to maintain
an adequate level of concrete within the casing so fluid trapped behind
the casing is displaced upward and discharged at the ground surface
without contaminating or displacing the shaft concrete.

Temporary casings that have become bound or fouled during shaft
construction and cannot be practically removed are considered to be a
defect in the drilled shaft. Correct defective shafts using approved
methods. Corrective action may consist of, but is not limited to, the
following:

**(1)** Removing the shaft concrete and extending the shaft deeper to
compensate for loss of frictional capacity in the cased zone;

**(2)** Providing straddle shafts to compensate for capacity loss; and

**(3)** Providing a replacement shaft.

When a casing is designated as permanent, cut the casing off at the
required elevation and leave in place.

**565.06 Reinforcing Steel for Drilled Shafts and Placement of Crosshole
Sonic Logging Access Tubes.** Perform the reinforcing steel work
according to Section 554. Securely wire together contact reinforcing
steel lap splices. Tie and support the reinforcing steel so it remains
within the required tolerances. Securely tie concrete spacers or other
approved spacing devices at fifth points around the cage perimeter and
space at intervals not to exceed 10 feet along the length of the cage.
Use spacers of approved material at least equal in quality and
durability to the shaft concrete.

Provide standard weight black steel pipe per ASTM A 53 with nominal
inside diameter of 2 inches for crosshole sonic logging access tubes.
Install the access tubes for each drilled shaft as shown in FLH T 521.
Use pipes and pipe joints that have a round, regular internal diameter,
free of defects or obstructions, and that will result in watertight
access tubes that permit the free, unobstructed passage of source and
receiver probes. Use access tubes that are free of corrosion, that have
clean internal and external faces to ensure probe passage, and that have
a good bond between the concrete and tubes. Do not use duct tape or
similar materials to seal joints. Do not use stiffening devices such as
mandrels in the access tubes during concrete placement. Fit the access
tubes with a water-tight shoe on the bottom and a removable cap on top.

Secure tubes firmly to the interior of the reinforcement cage. Install
the tubes in a regular, symmetric pattern according to FLH T 521 such
that each tube is spaced the maximum possible distance from each
adjacent tube. Tubes shall be as near to parallel as possible. The tubes
shall be installed from 1/2 foot above the shaft bottoms to at least 10
feet above the shaft tops, and at least 2 feet above the ground surface.
Do not bend or damage the tubes during reinforcement installation
operations.

Inspect the shaft by drilling test hole, standard penetration test, or
visual inspection. Place the reinforcing steel cage as a unit
immediately after the shaft excavation is inspected and accepted and
before concrete placement. If the concrete is not placed immediately
after the cage is installed, the cage may have to be removed before
placing the concrete to verify the integrity of the excavated area and
to ensure loose material is removed from the bottom of the hole. Handle
reinforcing cages to avoid distortion or racking of the steel.

During concrete placement, provide positive support from the top for the
reinforcing steel cage. Maintain the top of the reinforcing steel cage
no more than 6 inches above and no more than 3 inches below the required
position. If the reinforcing steel cage is not maintained within
tolerances, make acceptable corrections and do not construct additional
shafts until the method of reinforcing steel cage support has been
approved.

**565.07 Concrete for Drilled Shafts.** When the top of shaft is above
ground, use a removable form or other approved means to form the shaft
to at least 2 feet below finished ground. Forms may be removed provided
the requirements in Subsection 562.08 are complied with and the shaft
concrete has not been exposed to saltwater or moving water for 7 days.
Strip the forms without damaging the concrete.

Remove the top portion of the drilled shaft concrete before continuing
with column construction when it is determined the concrete has been
effected by underwater placement.

Place concrete immediately after all excavation is complete and the
reinforcing steel cage is in place.

Fill the crosshole sonic logging access tubes with clean water within 1
hour after concrete placement and replace the tube cap. Do not apply
excess torque, hammering, or other stress to the access tubes at any
time that could affect the concrete-tube bond.

Prepare ten 6-inch by 12-inch concrete cylinders for pulse velocity
testing from the same concrete mix used in the drilled shaft.

Furnish concrete conforming to Section 552 except as otherwise indicated
herein. For shafts constructed without drilling fluid, use class A
structural concrete having a slump of 71 inches. For shafts constructed
with drilling fluid, use class A structural concrete having a slump of
81 inches. Use seal concrete for under water placement. Do not use seal
concrete above the freeze/thaw or wet/dry zone of the hole. Place
underwater concrete according to Subsection 552.11(e) except as modified
herein. The method of underwater placement is subject to approval.

Adjust approved admixtures for project conditions to ensure that the
concrete has the minimum required slump for at least 2 hours. Submit
trial mix and slump loss test results for concrete at ambient
temperatures appropriate for site conditions.

Place each load of concrete within 2 hours of batching. Longer placement
time may be permitted if the concrete mix maintains the minimum required
slump for longer than 2 hours. Do not retemper concrete that has
developed its initial set.

Place concrete in one continuous operation from bottom to top of the
shaft. Continue placing concrete after the shaft excavation is full and
until acceptable quality concrete is evident at the top of shaft. Before
initial concrete set, consolidate the top 10 feet of the shaft concrete
using acceptable vibratory equipment. Finish the top of the shaft to +1
inch or -3 inches from the required elevation. For wet holes, do not
consolidate until all water or slurry above the concrete surface has
been removed. Place concrete either by free fall, tremie, or concrete
pump.

**(a) Free-fall concrete placement**. Use free-fall placement only in
dry holes with an 25-foot maximum height of free-fall. The concrete
shall fall directly to the shaft base without contacting either the
rebar cage or hole sidewall.

Drop chutes may be used to direct placement of free-fall concrete. Drop
chutes consist of a smooth tube of either one-piece construction or
sections that can be added and removed. Place concrete through a hopper
at the top of the tube or through side openings as the drop chute is
removed from the shaft during concrete placement. Support the drop chute
so that the maximum height of free-fall of the concrete measured from
the bottom of the chute is 25 feet. If concrete placement causes the
shaft excavation to cave or slough or if the concrete strikes the rebar
cage or sidewall, reduce the height of free-fall and reduce the rate of
concrete flow into the excavation. If placement cannot be satisfactorily
accomplished by free-fall, use tremie or pumping to place the concrete.

**(b) Tremies.** Use tremies for concrete placement in either wet or dry
holes. A tremie consists of a tube of sufficient length, mass, and
diameter to discharge concrete at the shaft base. Do not use tremies
that contain aluminum parts that will come in contact with the concrete.
Make the tremie inside diameter at least 6 times the maximum size of
aggregate used in the concrete mix and not less than 10 inches. Make the
inside and outside surfaces of the tremie clean and smooth. Make the
wall thick enough to prevent crimping or sharp bends.

Use a watertight tremie in accordance with Subsection 552.11(e) for wet
holes. Construct the discharge end of the tremie to permit free radial
flow of concrete during placement. Place the tremie discharge at the
shaft base elevation. Place the concrete in a continuous flow. Keep the
tremie discharge immersed at least 5 feet below the surface of the fluid
concrete. Maintain a positive head of concrete in the tremie at all
times. If at any time during the concrete placement, the tremie
discharge is removed from the fluid concrete column and discharges
concrete above the rising concrete surface into displaced water, remove
the reinforcing cage and concrete, complete any necessary sidewall
removal as directed, and reconstruct the shaft.

**(c) Pumped concrete.** Use pumped concrete placement in either wet or
dry holes. Use 4-inch minimum diameter discharge tubes with watertight
joints. Place the discharge tube at the shaft base elevation.

Use a sealed discharge tube according to Subsection 552.11(e) for wet
holes. If a plug is used, remove it from the hole or use a plug made
from approved material that will prevent a defect in the shaft if not
removed.

Place the concrete in a continuous flow. Keep pump discharge tube
immersed at least 5 feet below the surface of the fluid concrete. If at
any time during the concrete placement, the discharge tube is removed
from the fluid concrete column and discharges concrete above the rising
concrete surface into displaced water, remove the reinforcing cage and
concrete, complete any necessary sidewall removal as directed by the CO,
and reconstruct the shaft.

**565.08 Integrity Testing.**

**(a) Testing.** Perform integrity testing on all production drilled
shafts using FLH T 521, Standard Method for Determining Pulse Velocity
Through Concrete in Drilled Shafts. Test drilled shafts no earlier than
2 days and no later than 45 days after concrete placement. Before
testing, provide precise information as to drilled shaft bottom and tip
elevations, access tube lengths, surveyed tube positions, and date of
concrete placement.

Provide portable crosshole sonic logging testing equipment according to
FLH T 521 and provide the following:

**(1)** An ultrasonic source probe and one or more receiver probes able
to descend freely through a 2-inch inside diameter steel, water-filled
access tube.

**(2)** Capability to amplify/filter data and print ultrasonic logs on
site.

**(3)** An independent stable 110-volt, 60-hertz, alternating current
power supply if needed.

If access tubes are not acceptable for testing (e.g., tubes are not
plumb, tube does not retain water, tube-concrete debonding has occurred,
tube obstructions exist), provide replacement access tubes by core
drilling or propose an alternative test method that is acceptable to the
CO. After integrity testing, inspection and data analysis are completed
and accepted by the CO, fill access tubes with approved neat cement
slurry or grout from the bottom using a tremie.

Perform pulse velocity testing along the diametric axis of the concrete
cylinders according to ASTM C 597, Standard Test Method for Pulse
Velocity Through Concrete. Perform pulse velocity testing on two
concrete cylinders for each of the following cure times: 2 days, 7 days,
14 days, 21 days, and 28 days. After testing, break the two cylinders
according to AASHTO T 22. Report test results and prepare a graph of
pulse velocity and compressive strength versus times. Crosshole sonic
logging test results will be compared to pulse velocity results of the
same concrete age.

**(b) Test results and reporting.** Provide preliminary results to the
CO for each shaft tested before crosshole sonic logging personnel leave
the site. Within 5 days of testing, submit a detailed crosshole sonic
logging report and all test data in ASCII format with a header
(identifying shaft tested, tube coordinates, and each data column) to
the CO on a compact disk. Allow 5 days for the CO to conduct a review of
the data before any further construction on the tested shaft and before
issuing the final, written report.

Include the following in the crosshole sonic logging report: (1) project
identification and dates of testing; (2) table and a schematic showing
shafts tested with identification of tube coordinates and collar
elevation; (3) names of personnel that performed the
tests/interpretation and their affiliation; (4) equipment used; (5) data
logs; (6) XY plots of first arrival times, amplitude, and velocity
versus depth; and (7) interpretation, analysis, and results. Determine
the velocity reduction by comparing the velocities achieved in the
drilled shaft to the pulse velocity testing on the cylinders constructed
from the same concrete and of the same age as the drilled shaft.

Where velocity reductions are greater than 20 percent, process the data
and construct easy-to-understand two-dimensional cross-sections between
tubes and three-dimensional volumetric images for the entire shaft. The
cross-sections shall be color-coded tomographic images indications
velocity variations along the shaft. Identify the location and geometry
of defective zones (those with velocity reductions of greater than 20
percent) in three-dimensional color images and provide a detailed
discussion of each.

**565.09 Acceptance.** Material for mineral slurry will be evaluated
under Subsections 106.02 and 106.03.

Concrete will be evaluated under Section 552. Concrete, tremie placed or
pumped, will be sampled at point of discharge into the tremie or
concrete pump hopper.

Reinforcing steel will be evaluated under Section 554.

Construction of drilled shafts will be evaluated under Subsections
106.02, 106.03, and 106.04 as follows:

**(a)** Drilled shafts with velocity reductions not exceeding 20 percent
are acceptable.

**(b)** Where velocity reductions exceed 20 percent, furnish additional
imaging and other data required in Subsection 565.08(b) to enable
further evaluation of the shaft. When required by the CO, drill a
minimum of two cores to intercept the imaged defect and obtain core
samples from these suspect area. The CO will evaluate the cross-hole
sonic logging data, the imaging data, and the core data and make a
determination as to the presence of substantive defects.

If a shaft is determined to have substantive defects, submit a plan
according to Subsection 106.01 to remove and replace, correct, or modify
the work. Proposed modifications to the drilled shaft or load transfer
mechanisms shall be designed and stamped by a professional engineer.
Include drawings stamped by a professional engineer for all foundation
elements affected. Do not begin remedial work until the CO has approved
the plan.

Measurement

**565.10** Measure the Section 565 items listed in the bid schedule
according to Subsection 109.02 and the following as applicable.

Measure drilled shafts from the plan top elevation to the approved tip.
Do not measure portions of shafts extending deeper than approved.

Do not measure concrete or reinforcing steel.

Measure trial drilled shafts, determined to be satisfactory, from the
approved tip elevation to the ground surface at the center of the shaft.

Payment

**565.11** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 565 pay items listed in the bid
schedule except the drilled shaft contract unit bid price will be
adjusted according to Subsection 106.05. Payment will be full
compensation for the work prescribed in this Section. See Subsection
109.05.

Payment for drilled shafts will be made at a price determined by
multiplying the unit bid price by the compressive strength pay factor.

## Section 566. --- SHOTCRETE

Description

**566.01** This work consists of constructing one or more courses of
shotcrete on a prepared surface.

Shotcrete aggregate grading is designated as shown in Table 703-15.

Material

**566.02** Conform to the following Subsections:

Air-entraining admixture (wet mix only) 711.02

Chemical admixtures (wet mix only) 711.03

Concrete coloring agents 711.05

Curing material 711.01

Hydraulic cement 701.01

Penetrating stain 708.05

Pozzolans 725.04

Reinforcing fibers 725.29

Reinforcing steel 709.01

Shotcrete aggregate 703.18

Water 725.01(a)

Construction Requirements

**566.03 Composition (Shotcrete Mix Design).** Design and produce
shotcrete mixtures that conform to Table 566-1. Shotcrete mixtures shall
also conform to the following ACI specifications.

• ACI 506R Guide to Shotcrete;

• ACI 506.1 State of the Art Report on Fiber Reinforced Shotcrete; and

• ACI 506.2 Specifications for Proportioning Application of Shotcrete.

Verify mix design with trial mixes prepared from the same source
proposed for use. Submit the following for acceptance at least 36 days
before placing shotcrete:

**(a)** Proposed shotcrete mix design with mix proportions. Include the
dosage and type of any admixture with proposed mix design.

Table 566-1

Composition of Shotcrete

+----------+----------------+----------+-----------+-----------------+
| **Type   | **Minimum      | *        | **Air     | **Minimum       |
| of       | Cement         | *Maximum | Content   | 28-Day Strength |
| S        | Content**      | W/C      | Range %** | (pounds per     |
| hotcrete |                | Ratio**  |           | square inch)**  |
| P        | **(pounds per  |          |           |                 |
| rocess** | cubic yard)**  |          |           |                 |
+----------+----------------+----------+-----------+-----------------+
| **Wet**  | 546            | 0.55     | NA        | 4000            |
+----------+----------------+----------+-----------+-----------------+
| **Dry**  | 546            | 0.50     | NA        | 4000            |
+----------+----------------+----------+-----------+-----------------+
| **Wet    | 546            | 0.45     | 5 min.    | 4000            |
| (AE)**   |                |          |           |                 |
+----------+----------------+----------+-----------+-----------------+
| **Dry    | 546            | 0.45     | 5 min.    | 4000            |
| (AE)**   |                |          |           |                 |
+----------+----------------+----------+-----------+-----------------+

**(b)** Representative samples of shotcrete material, if requested by
the CO. Results of shotcrete preconstruction testing.

**(c)** Proposed method for applying shotcrete.

**(d)** Other information necessary to verify compliance with ACI 506.2.

**(e)** Shotcrete materials certifications.

**(f)** Fiber samples, if used.

**(g)** Description of proposed equipment for mixing and applying
shotcrete. Include the manufacturer's instructions, recommendations,
literature, performance, and test data. In addition to meeting equipment
requirements in ACI 506, provide the following:

**(1) Water supply system.** For dry mix, provide a job site water
storage tank. Provide a positive displacement pump with a regulating
valve that is accurately controlled to provide water at the required
pressure and volume.

**(2) Mixing.** Use equipment capable of handling and applying shotcrete
containing the specified maximum size aggregate and admixtures. Provide
an air hose and blow pipe to clear dust and rebound during shotcrete
application.

**(h)** Qualifications. Demonstrate satisfactory completion of at least
3 comparable projects. Provide Foremen experienced in shotcrete
construction on at least 5 comparable projects. At least 30 days before
starting shotcrete work, identify foremen and nozzlemen assigned to the
project and submit a summary of each individual's experience.

**566.04 Hydration Stabilizing Admixtures.** When hydration stabilizing
admixtures are used to extend the allowable delivery time for shotcrete,
include the admixtures in the shotcrete mix design. Base dosage on the
time needed to delay the initial set of the shotcrete for delivery and
discharge on the job. Include the design discharge time limit in the
dosage submittal. The maximum allowable design discharge time is 3.5
hours.

Use an approved and compatible hydration activator at the discharge site
to ensure proper placement and testing.

Determine dosage required to stabilize shotcrete using job site material
and field trial mixtures. The extended-set admixture shall control the
hydration of all cement minerals and gypsum.

When requested, the admixture manufacturer shall provide the service of
a qualified person to assist in establishing the proper dose of
extended-set admixture and to make dosage adjustments required to meet
changing job site conditions.

**566.05 Preconstruction Testing.** Conduct preconstruction shotcrete
field trials before starting shotcrete production.

**(a) Field trials.** Construct test panels from 24-inch by 24-inch by 6
inches wood forms. Have each proposed nozzleman produce shotcrete panels
on two vertical wood forms. Cure the test panels according to AASHTO T
23 except do not immerse the panels.

**(b) Coring.** Take six 3-inch diameter cores from each test panel
according to AASHTO T 24. Trim the ends of the cores according to AASHTO
T 24 to make cores at least 3 inches long.

**(c) Compressive strength testing.** Soak the cores in water for 40
hours immediately before testing. Test three cores from each test panel
four days after the field trial and test the remaining three cores 28
days after the field trial. Perform tests according to AASHTO T 23.

**(d) Mix design acceptance.** Submit the test data and a visual
description of each core to the CO. Include details concerning presence
of voids, sand pockets, lamination, and other inadequacies. Acceptance
of the nozzlemen and mix design will be based on preconstruction field
trials and test results. The visual quality of the cores shall not be
lower than grade 2 according to shotcrete grading requirements of ACI
506.2.

Submit field quality control test reports within two working days of
performing the tests. Include the following information in the reports:

• Sample identification including mix design and test panel number and
orientation;

• Date and time of sample preparation including curing conditions and
sample dimensions;

• Date, time, and type of test;

• Complete test results including load and deformation data during
testing, sketch of sample before and after testing, and any unusual
occurrences observed;

• Name and signature of person performing the test;

• Location of steel reinforcement, if used, covered by shotcrete; and

• Name of nozzleman.

**566.06 Shotcrete Construction.** Apply shotcrete according to ACI 506R
and the following.

**(a) Surface preparation.** Remove curing compound on previously-placed
shotcrete surfaces by sandblasting. Install approved depth gauges to
indicate the thickness of the shotcrete layers. Install depth gauges on
6-foot centers longitudinally and transversely with no less than two
gauges per increment of surface area to receive the shotcrete. Moisten
all surfaces.

**(b) Temperature and Weather Conditions.** Maintain the temperature of
the shotcrete mix between 50 F and 90 F. Place shotcrete when the
surface and ambient temperature is at least 40 F and rising. Do not
perform shotcrete operations during high winds and heavy rains.

**(c) Shotcrete application.** Use the same nozzlemen that created
acceptable test panels.

**(1)** Apply shotcrete within 45 minutes of adding cement to the
mixture.

**(2)** Limit the layer thickness of each shotcrete application to 2
inches. Thicker applications may be approved if the Contractor can
demonstrate that no sloughing or sagging is occurring. If additional
thickness is required, broom or scarify the applied surface and allow
the layer to harden. Dampen the surface before applying an additional
layer.

**(3)** Remove laitance, loose material, and rebound. Promptly remove
rebound from the work area.

**(4)** Taper construction joints to a thin edge over a distance of at
least 12 inches. Wet the joint surface before placing additional
shotcrete on the joint. Do not use square construction joints.

**(5)** Finish shotcrete as specified.

**566.07 Curing Shotcrete.** Cure the surface according to Subsection
552.15. For intermediate shotcrete surfaces or if a stained or finished
final surface is required, cure the shotcrete according to Subsection
552.15(b). If no stained or finished surface is required, apply curing
compound to the final exposed shotcrete surface according to Subsection
552.15(c). Maintain shotcrete at a temperature above 40 F until
shotcrete has achieved a minimum compressive strength of 750 pounds per
square inch.

**566.08 Production Report.** Prepare and submit a written report within
24 hours of shotcrete production and application for each shift. Include
the following information in the report:

**(a)** Quantity and location of shotcrete applied including sketches of
areas where shotcrete was placed.

**(b)** Observations of success or problems of equipment operation,
application, final product condition, and any other relevant issues
during production and application.

**(c)** Batch number(s) if applicable.

**(d)** Name of nozzleman.

**(e)** Names and signature of person performing the observation.

**566.09 Acceptance.** See Table 566-2 for sampling and testing
requirements and the acceptance quality characteristic category.

Material for shotcrete will be evaluated under Subsections 106.02 and
106.03. Furnish a production certification for the hydraulic cement.

The shotcrete placement system will be evaluated under Subsections
106.02 and 106.04.

The shotcrete mixtures air content and unit mass will be evaluated under
Subsections 106.02 and 106.04. Compressive strength will be evaluated
under Subsection 106.05. See Table 566-1 for specification limits.

Measurement

**566.10** Measure the Section 566 items listed in the bid schedule
according to Subsection 109.02 and the following as applicable.

Measure shotcrete by the cubic yard in place.

Payment

**566.11** The accepted quantities will be paid at the contract price
per unit of measurement for the Section 566 pay items listed in the bid
schedule except the shotcrete unit bid price will be adjusted according
to Subsection 106.05. Payment will be full compensation for the work
prescribed in this Section. See Subsection 109.05.

Payment for shotcrete will be made at a price determined by multiplying
the unit bid price by the compressive strength pay factor.

<table>
<colgroup>
<col style="width: 8%" />
<col style="width: 7%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 14%" />
<col style="width: 7%" />
<col style="width: 8%" />
<col style="width: 6%" />
<col style="width: 7%" />
<col style="width: 3%" />
<col style="width: 3%" />
<col style="width: 8%" />
<col style="width: 3%" />
</colgroup>
<tbody>
<tr class="odd">
<td rowspan="9"><p>Table 566-2</p>
<p>Sampling and Testing Requirements</p></td>
<td><strong>Reporting Time</strong></td>
<td><p>Before</p>
<p>producing</p></td>
<td><p>Before</p>
<p>producing</p></td>
<td><p>Before</p>
<p>batching</p></td>
<td>“</td>
<td><p>Upon</p>
<p>completing</p>
<p>tests</p></td>
<td>“</td>
<td>Note 3</td>
<td rowspan="9">(1) See Subsection 552.09(b)(3).</td>
<td rowspan="9">(2) Sample according to AASHTO T 141.</td>
<td rowspan="9">(3) Prepare production test panels according to
Subsection 566.07(a). Obtain two 3-inch diameter core specimens from
each panel according to AASHTO T 24. A single compressive strength test
result is the average result from two 3-inch diameter core specimens
from the same test panel tested according to AASHTO T 23 at 28
days.</td>
<td rowspan="9">(4) Deliver cores to designated laboratory for
testing.</td>
</tr>
<tr class="even">
<td><p><strong>Split</strong></p>
<p><strong>Sample</strong></p></td>
<td>Yes</td>
<td>Yes</td>
<td>Yes, when requested</td>
<td>“</td>
<td>—</td>
<td>—</td>
<td>Note 4</td>
</tr>
<tr class="odd">
<td><strong>Point of Sampling</strong></td>
<td><p>Source of</p>
<p>material</p></td>
<td><p>Source of</p>
<p>material</p></td>
<td><p>Flowing aggregate stream (bin,</p>
<p>belt, discharge conveyor belt, or stockpile)</p></td>
<td>“</td>
<td>Truck mixer or agitator<sup>(2)</sup></td>
<td>“</td>
<td>Production test panels</td>
</tr>
<tr class="even">
<td><p><strong>Sample</strong></p>
<p><strong>Frequency</strong></p></td>
<td>1 per material type</td>
<td>1 per mix design</td>
<td>1 per material type</td>
<td>—</td>
<td>1 per load <sup>(1)</sup></td>
<td>“</td>
<td>1 set per 30 yd<sup>3</sup> but not less than 1 per day</td>
</tr>
<tr class="odd">
<td><strong>Test Methods or Specifications</strong></td>
<td>AASHTO M 80</td>
<td>Subsection 566.03</td>
<td><p>AASHTO T 27</p>
<p>&amp; T 11</p></td>
<td>“</td>
<td>AASHTO T 121</td>
<td><p>AASHTO T 152 or</p>
<p>T 196</p></td>
<td>AASHTO T 24</td>
</tr>
<tr class="even">
<td><strong>Category</strong></td>
<td>—</td>
<td>—</td>
<td>—</td>
<td>—</td>
<td>—</td>
<td>—</td>
<td>II</td>
</tr>
<tr class="odd">
<td><strong>Characteristic</strong></td>
<td>Quality</td>
<td>All</td>
<td>Gradation</td>
<td><p>Fineness</p>
<p>modulus</p></td>
<td>Unit mass</td>
<td>Air content</td>
<td>Compressive strength</td>
</tr>
<tr class="even">
<td><strong>Type of Acceptance (Subsection)</strong></td>
<td><p>Measured and tested</p>
<p>for conformance</p>
<p>(106.04 &amp; 105)</p></td>
<td><p>Measured and tested</p>
<p>for conformance</p>
<p>(106.04)</p></td>
<td colspan="2"><p>Measured and tested</p>
<p>for conformance</p>
<p>(106.04)</p></td>
<td colspan="2"><p>Measured and tested</p>
<p>for conformance</p>
<p>(106.04)</p></td>
<td><p>Statistical</p>
<p>(106.05)</p></td>
</tr>
<tr class="odd">
<td><strong>Material or Product</strong></td>
<td><p>Aggregate source quality</p>
<p>(703.18)</p></td>
<td><p>Shotcrete composition</p>
<p>(mix design)</p></td>
<td colspan="2"><p>Production</p>
<p>aggregate</p>
<p>(fine &amp; course)</p></td>
<td colspan="3">Shotcrete</td>
</tr>
</tbody>
</table>