# PART III -- FLEXIBLE BASE COURSES

### **ITEM P-208 AGGREGATE BASE COURSE**

**208-1.1** This item shall consist of a base course composed of
**\[crushed\] \[uncrushed\]** coarse aggregate bonded with either soil
or fine aggregate or both.  It shall be constructed on a prepared
underlying course in accordance with these specifications and shall
conform to the dimensions and typical cross section shown on the plans.

MATERIALS

**208-2.1 UNCRUSHED COARSE AGGREGATE**.  The base course material shall
consist of hard, durable particles or fragments of stone or gravel mixed
or blended with sand, stone dust, or other similar binding or filler
materials produced from approved sources.  All oversized stones, rocks
and boulders occurring in the pit or quarry material shall be wasted;
those of acceptable quality may be crushed and become a part of the base
material, provided the blend meets the specified gradations.  The
aggregate shall be free from vegetation, lumps, or excessive amounts of
clay and other objectionable substances.  The coarse aggregate shall
have a percent of wear not more than 45 at 500 revolutions as determined
by ASTM C 131.

**208-2.2 CRUSHED COARSE AGGREGATE**.  The aggregates shall consist of
both fine and coarse fragments of crushed stone, crushed slag, or
crushed gravel mixed or blended with sand, screenings, or other similar
approved materials.  The crushed stone shall consist of hard, durable
particles or fragments of stone and shall be free from excess flat,
elongated, soft or disintegrated pieces, dirt, or other objectionable
matter.

The crushed slag shall be air-cooled, blast furnace slag and shall
consist of angular fragments reasonably uniform in density and quality
and shall be reasonably free from thin, elongated, or soft pieces, dirt,
and other objectionable matter.  It shall weigh not less than 70 pounds
per cubic foot (1.12 Mg/cubic meter) as determined by ASTM C 29.

The crushed gravel shall consist of hard, durable stones, rock, and
boulders crushed to specified size and shall be free from excess flat,
elongated, soft or disintegrated pieces, dirt, or other objectionable
matter.  The method used in production of crushed gravel shall be such
that the fractured particles occurring in the finished product shall be
as nearly constant and uniform as practicable and shall result in a
minimum of 60% of the material retained on the No. 4 sieve having at
least 2 fractured faces and 75% having at least 1 fractured face.

If necessary to meet this requirement or to eliminate an excess of fine,
uncrushed particles, the gravel shall be screened before crushing.  All
stones, rocks, and boulders of inferior quality in the pit shall be
wasted.

The crushed coarse aggregate shall have a percent of wear not more than
50 at 500 revolutions as determined by ASTM C 131.

All material passing the No. 4 mesh (4.75 mm) sieve produced in the
crushing operation of either stone, slag, or gravel shall be
incorporated in the base material to the extent permitted by the
gradation requirements.

**208-2.3 GRADATION**.  The gradation of the uncrushed or crushed
material shall meet the requirements of one of the gradations given in
Table 1 when tested in accordance with ASTM C 117, ASTM C 136, and ASTM
D 422.

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> **Include testing frequencies for the particle size distribution.**

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**TABLE 1. REQUIREMENTS FOR GRADATION OF AGGREGATE**

  ---------------------- --------------- ------------------ ------------------
  **Sieve Designation**  **Percentage by                    
                         weight passing                     
                         sieves**                           

                                                            

                         **2\'\'         **1 1/2\'\'        **1\'\'maximum**
                         maximum**       maximum**          

                                                            

  2 inch (50.0 mm)       100             \--                \--

  1‑1/2 inch (37.0 mm)   70-100          100                \--

  1 inch (25.0 mm)       55-85           70-100             100

  3/4 inch (13.0 mm)     50-80           55-85              70-100

  No. 4 (4.75 mm)        30-60           30-60              35-65

  No. 40 (0.45 mm)       10-30           10-30              10-25

  No. 200 (0.075 mm)     5-15            5-15               5-15
  ---------------------- --------------- ------------------ ------------------

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> **For frost areas, add requirements for the material finer than 0.02
> mm to a maximum of 3% and the range for the 200 sieve to between 0 and
> 8%.**

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The gradations in the table represent the limits that shall determine
suitability of aggregate for use from the sources of supply.  The final
gradations decided on within the limits designated in the table shall be
well graded from coarse to fine and shall not vary from the low limit on
one sieve to the high limit on the adjacent sieves, or vice versa.

The amount of the fraction of material passing the No. 200 mesh (0.075
mm) sieve shall not exceed one-half the fraction passing the No. 40 mesh
(0.45 mm) sieve. The aggregate blend shall not contain more than 3%
material finer than 0.02 mm unless all materials are produced from
crushed stone.

The portion of the filler and binder, including any blended material,
passing the No. 40 mesh (0.45 mm) sieve have a liquid limit not more
than 25 and a plasticity index not more than 6 when tested in accordance
with ASTM D 4318.

The selection of any of the gradations shown in the table shall be such
that the maximum size aggregate used in any course shall be not more
than two-thirds the thickness of the layer of the course being
constructed.

**208-2.4 FILLER FOR BLENDING**.  If filler, in addition to that
naturally present in the base course material, is necessary for
satisfactory bonding of the material, for changing the soil constants of
the material passing the No. 40 mesh (0.45 mm) sieve, or for correcting
the gradation to the limitations of the specified gradation, it shall be
uniformly blended with the base course material at the crushing plant or
at the mixing plant.  The material for such purpose shall be obtained
from sources approved by the Engineer and shall be of a gradation
necessary to accomplish the specified gradation in the finally processed
material.

The additional filler may be composed of sand, but the amount of sand
shall not exceed 20% by weight of the total combined base aggregate. 
All the sand shall pass a No. 4 mesh (4.75 mm) sieve and not more than
5% by weight shall pass a No. 200 mesh (0.075 mm) sieve.

CONSTRUCTION METHODS

**208-3.1 OPERATIONS IN PITS AND QUARRIES**.  All work involved in
clearing and stripping pits and quarries, including handling of
unsuitable material, shall be performed by the Contractor.  All material
shall be handled in a manner that shall secure a uniform and
satisfactory base product.  The base course material shall be obtained
from sources that have been approved.

**208-3.2 PREPARING UNDERLYING COURSE**.  The underlying course shall be
checked and accepted by the Engineer before placing and spreading
operations are started.  Any ruts or soft, yielding places due to
improper drainage conditions, hauling, or any other cause, shall be
corrected and rolled to the required density before the base course is
placed thereon.

To protect the underlying course and to ensure proper drainage, the
spreading of the base shall begin along the centerline of the pavement
on a crowned section or on the high side of the pavement with a one-way
slope.

**208-3.3 METHODS OF PRODUCTION**

**a. Plant Mix**.  When provided in the proposal, or when selected by
the Contractor and approved by the Engineer, the base material shall be
uniformly blended or mixed in an approved plant.  The mixing plant shall
include bins for storage and batching of the aggregate, pump and tanks
for water, and batch mixers of either the pugmill or drum type.  All
mineral aggregates shall be batched into the mixer by weight.  The
agitation shall be such that a thorough dispersion of moisture is
obtained.  The size of the batch and the time of mixing shall be fixed
by the Engineer and shall produce the results and requirements
specified.  The base course material produced by combining two or more
materials from different sources shall be mixed in a mixing plant
described herein.  The mixture material shall be at a satisfactory
moisture content to obtain maximum density.

**b. Travel Plant**.  When the use of a traveling plant is allowed, the
plant shall blend and mix the materials to meet these specifications. 
It shall accomplish a thorough mixing in one trip.  The agitation shall
be such that the dispersion of the moisture is complete.  The machine
shall move at a uniform rate of speed and this speed shall be regulated
to fix the mixing time.  If a windrow-type of travel plant is employed
for mixing, the aggregate shall be placed in windrows parallel to the
pavement centerline.

The windrow volume shall be sufficient to cover exact areas as planned. 
The windrow contents shall produce a mixture of the required gradation
and bonding qualities.  If a travel plant is used which is of the type
that mixes previously spread aggregates in-place, the material shall
have been spread in such thickness and proportions as may be handled by
the machine to develop a base course of the thickness of each layer and
of the gradation required.  With either type of equipment, the mixed
material shall be at a satisfactory moisture content to obtain the
maximum density.

**c. Materials of Proper Gradation**.  When the entire base course
material from coarse to fine is secured in a uniform and well-graded
condition and contains approximately the proper moisture, such approved
material may be handled directly to the spreading equipment.  The
material may be obtained from gravel pits, stockpiles, or produced from
a crushing and screening plant with the proper blending.  The materials
from these sources shall meet the requirements for gradation, quality,
and consistency.  The intent of this section of these specifications is
to secure materials that will not require further mixing.  The base
material shall be at a satisfactory moisture content to obtain maximum
density.  Any minor deficiency or excess of moisture may be corrected by
surface sprinkling or by aeration.  In such instances some mixing or
manipulation may be required immediately preceding the rolling to obtain
the required moisture content.  The final operation shall be blading, if
necessary, to obtain a smooth uniform surface true to line and grade.

**208-3.4 PLACING**.

**a.** The aggregate base material that is correctly proportioned, or
has been processed in a plant, shall be placed on the prepared
underlying course and compacted in layers of the thickness shown on the
plans.  The depositing and spreading of the material shall commence
where designated and shall progress continuously without breaks.  The
material shall be deposited and spread in lanes in a uniform layer and
without segregation of size to such loose depth that, when compacted,
the layer shall have the required thickness.  The base aggregate shall
be spread by spreader boxes or other approved devices having positive
thickness controls that shall spread the aggregate in the required
amount to avoid or minimize the need for hand manipulation.  Dumping
from vehicles in piles that require rehandling shall not be permitted. 
Hauling over the uncompacted base course shall not be permitted.

**b.**  The aggregate base material that has been processed in a
traveling plant, or mixed and blended in-place, shall be spread in a
uniform layer of required depth and width and to the typical cross
section.  The spreading shall be by a self-powered blade grader,
mechanical spreader, or other approved method.  In spreading, care shall
be taken to prevent cutting into the underlying layer.  The material
shall be bladed until a smooth, uniform surface is obtained, true to
line and grade.

**c.**  The base course shall be constructed in a layer not less than 3
inches (75 mm) nor more than 6 inches (150 mm) of compacted thickness. 
The aggregate as spread shall be of uniform grading with no pockets of
fine or coarse materials.  The aggregate, unless otherwise permitted by
the Engineer, shall not be spread more than 2,000 square yards (1700
square meters) in advance of the rolling.  Any necessary sprinkling
shall be kept within these limits.  No material shall be placed in snow
or on a soft, muddy, or frozen course.

When more than one layer is required, the construction procedure
described herein shall apply similarly to each layer.

During the mixing and spreading process, sufficient caution shall be
exercised to prevent the incorporation of subgrade, subbase, or shoulder
material in the base course mixture.

**208-3.5 COMPACTION**.  Immediately upon completion of the spreading
operations, the aggregate shall be thoroughly compacted.  The number,
type, and weight of rollers shall be sufficient to compact the material
to the required density.

The moisture content of the material during placing operations shall not
be below, nor more than 2 percentage points above, the optimum moisture
content as determined by ASTM **\[ \]**.

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> **If nuclear density machines are to be used for density
> determination, the machines shall be calibrated in accordance with
> ASTM D 2922. The nuclear equipment shall be calibrated using blocks of
> materials with densities that extend through a range representative of
> the density of the proposed base material. ASTM D 3017 may be used to
> determine the moisture content of the material. (See Section 120 of
> the General Provisions for additional guidance)**

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**208-3.6 ACCEPTANCE SAMPLING AND TESTING FOR DENSITY**.  Aggregate base
course shall be accepted for density on a lot basis.  A lot will consist
of one day\'s production where it is not expected to exceed 2400 square
yards (2000 square meters).  A lot will consist of one-half day\'s
production where a day\'s production is expected to consist of between
2400 and 4800 square yards (2000 and 4000 square meters).

Each lot shall be divided into two equal sublots.  One test shall be
made for each sublot.  Sampling locations will be determined by the
Engineer on a random basis in accordance with statistical procedures
contained in ASTM D 3665.

Each lot will be accepted for density when the field density is at least
100 percent of the maximum density of laboratory specimens prepared from
samples of the material delivered to the jobsite.  The specimens shall
be compacted and tested in accordance with ASTM **\[ \]**.  The in-place
field density shall be determined in accordance with ASTM D 1556 or ASTM
D 2167.  If the specified density is not attained, the entire lot shall
be reworked and/or recompacted and two additional random tests made. 
This procedure shall be followed until the specified density is reached.

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> **The Engineer shall specify ASTM D 698 for areas designated for
> aircraft with gross weights of 60,000 pounds (27 200 kg) or less and
> ASTM D 1557 for areas designated for aircraft with gross weights
> greater than 60,000 pounds (27 200 kg).**
>
> **If nuclear density machines are to be used for density
> determination, the machines shall be calibrated in accordance with
> ASTM D 2922. The nuclear equipment shall be calibrated using blocks of
> materials with densities that extend through a range representative of
> the density of the proposed base material. ASTM 3017 may be used to
> determine the moisture content of the material. (See Section 120 of
> the General Provisions for additional guidance)**

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**208-3.7 SURFACE TEST**.  After the course has been completely
compacted, the surface shall be tested for smoothness and accuracy of
grade and crown.  Any portion lacking the required smoothness or failing
in accuracy of grade or crown shall be scarified, reshaped, recompacted,
and otherwise manipulated as the Engineer may direct until the required
smoothness and accuracy are obtained.  The finished surface shall not
vary more than 3/8 inch (9 mm) from a 16-foot (4.8 m) straightedge when
applied to the surface parallel with, and at right angles to, the
centerline.

**208-3.8 THICKNESS**.  The thickness of the base course shall be
determined by depth tests or cores taken at intervals in such manner
that each test shall represent no more than 300 square yards (250 square
meters).  When the base deficiency is more than 1/2 inch (12 mm), the
Contractor shall correct such areas by scarifying, adding satisfactory
base mixture, rolling, sprinkling, reshaping, and finishing in
accordance with these specifications.  The Contractor shall replace, at
his/her expense, the base material where borings have been taken for
test purposes.

**208-3.9 PROTECTION**.  Work on the base course shall not be
accomplished during freezing temperatures nor when the subgrade is wet. 
When the aggregates contain frozen materials or when the underlying
course is frozen, the construction shall be stopped.

Hauling equipment may be routed over completed portions of the base
course, provided no damage results and provided that such equipment is
routed over the full width of the base course to avoid rutting or uneven
compaction.  However, the Engineer in charge shall have full and
specific authority to stop all hauling over completed or partially
completed base course when, in his/her opinion, such hauling is causing
damage.  Any damage resulting to the base course from routing equipment
over the base course shall be repaired by the Contractor at his/her own
expense.

**208-3.10 MAINTENANCE**.  Following the completion of the base course,
the Contractor shall perform all maintenance work necessary to keep the
base course in a condition satisfactory for priming.  After priming, the
surface shall be kept clean and free from foreign material.  The base
course shall be properly drained at all times.  If cleaning is
necessary, or if the prime coat becomes disturbed, any work or
restitution necessary shall be performed at the expense of the
Contractor.

Before preparations begin for the application of a surface treatment or
for a surface course, the base course shall be allowed to partially dry
until the average moisture content of the full depth of base is less
than 80% of the optimum moisture of the base mixture.  The drying shall
not continue to the extent that the surface of the base becomes dusty
with consequent loss of binder.  If during the curing period the surface
of the base dries too fast, it shall be kept moist by sprinkling until
such time as the prime coat is applied as directed.

The Contractor shall remove all survey and grade hubs from the base
courses prior to placing any bituminous surface course.

METHOD OF MEASUREMENT

**208-4.1**  The quantity of **\[uncrushed\]\[crushed\]** aggregate base
course to be paid for shall be the number of cubic yards (cubic meters)
of base course material placed, bonded, and accepted in the completed
base course.  The quantity of base course material shall be measured in
final position based upon depth test, or cores taken as directed by the
Engineer, or at the rate of 1 depth test for each 300 square yards (250
square meters) of base course, or by means of average end areas on the
complete work computed from elevations to the nearest 0.01 foot (3 mm). 
On individual depth measurements, thicknesses more than 1/2 inch (12 mm)
in excess of that shown on the plans shall be considered as specified
thickness plus 1/2 inch (12 mm) in computing the yardage for payment. 
Base materials shall not be included in any other excavation quantities.

BASIS OF PAYMENT

**208-5.1**  Payment shall be made at the contract unit price per cubic
yard (cubic meter) for aggregate base course.  This price shall be full
compensation for furnishing all materials and for all operations,
hauling, and placing of these materials, and for all labor, equipment,
tools, and incidentals necessary to complete the item.

Payment will be made under:

Item P-208-5.1 **\[Uncrushed\]\[Crushed\]** Aggregate Base Course---per
cubic yard (cubic meter)

TESTING REQUIREMENTS

ASTM C 29 Unit Weight of Aggregate

ASTM C 117 Materials Finer than 75μm (No. 200) Sieve in Mineral
Aggregates by Washing

ASTM C 131 Resistance to Abrasion of Small Size Coarse Aggregate by Use
of the Los Angeles Machine

ASTM C 136 Sieve Analysis of Fine and Coarse Aggregates

ASTM D 422 Particle Size Analysis of Soils

ASTM D 698 Moisture-Density Relations of Soils and Soil-Aggregate
Mixtures Using 5.5 lb (2.49 kg) Rammer and 12-in (305 mm) Drop

ASTM D 1556 Density of Soil in Place by the Sand-Cone Method

ASTM D 1557 Test for Laboratory Compaction Characteristics of Soil Using
Modified Effort

ASTM D 2167 Density of Soil in Place by the Rubber-Ballon Method

ASTM D 3665 Random Sampling of Paving Materials

ASTM D 4318 Liquid Limit, Plastic Limit, and Plasticity Index of Soils

END OF ITEM P-208

### **ITEM P-209 CRUSHED AGGREGATE BASE COURSE**

DESCRIPTION

**209-1.1**  This item consists of a base course composed of crushed
aggregates constructed on a prepared course in accordance with these
specifications and in conformity to the dimensions and typical cross
sections shown on the plans.

MATERIALS

**209-2.1 AGGREGATE**.  Aggregates shall consist of clean, sound,
durable particles of crushed stone, crushed gravel, or crushed slag and
shall be free from coatings of clay, silt, vegetable matter, and other
objectionable materials and shall contain no clay balls.  Fine aggregate
passing the No. 4 (4.75 mm) sieve shall consist of fines from the
operation of crushing the coarse aggregate.  If necessary, fine
aggregate may be added to produce the correct gradation.  The fine
aggregate shall be produced by crushing stone, gravel, or slag that meet
the requirements for wear and soundness specified for coarse aggregate.

The crushed slag shall be an air-cooled, blast furnace slag and shall
have a unit weight of not less than 70 pounds per cubic foot (1.12
Mg/cubic meter) when tested in accordance with ASTM C 29.

The coarse aggregate portion, defined as the material retained on the
No. 4 (4.75 mm) sieve and larger, shall contain not more than 15
percent, by weight, of flat or elongated pieces as defined in ASTM D 693
and shall have at least 90 percent by weight of particles with at least
two fractured faces and 100 percent with at least one fractured face. 
The area of each face shall be equal to at least 75 percent of the
smallest midsectional area of the piece.  When two fractured faces are
contiguous, the angle between the planes of fractures shall be at least
30 to count as two fractured faces.

The percentage of wear shall not be greater than 45 percent when tested
in accordance with ASTM C 131.  The sodium sulfate soundness loss shall
not exceed 12 percent, after 5 cycles, when tested in accordance with
ASTM C 88.

The fraction passing the No. 40 (0.42 mm) sieve shall have a liquid
limit no greater than 25 and a plasticity index of not more than 4 when
tested in accordance with ASTM D 4318.  The fine aggregate shall have a
minimum sand equivalent value of 35 when tested in accordance with ASTM
D 2419.

**a. Sampling and Testing**.  Aggregates for preliminary testing shall
be furnished by the Contractor prior to the start of production.  All
tests for initial aggregate submittals necessary to determine compliance
with the specification requirements will be made by the Engineer at no
expense to the Contractor.

Samples of aggregates shall be furnished by the Contractor at the start
of production and at intervals during production.  The sampling points
and intervals will be designated by the Engineer.  The samples will be
the basis of approval of specific lots of aggregates from the standpoint
of the quality requirements of this section.

In lieu of testing, the Engineer may accept certified state test results
indicating that the aggregate meets specification requirements.
Certified test results shall be less than 6 months old.

Samples of aggregates to check gradation shall be taken by the Engineer
at least two per lot.  The lot will be consistent with acceptable
sampling for density. The samples shall be taken from the in-place,
compacted material. Sampling shall be in accordance with ASTM D 75, and
testing shall be in accordance with ASTM C 136 and ASTM C 117.

**b. Gradation Requirements**.  The gradation (job mix) of the final
mixture shall fall within the design range indicated in Table 1, when
tested in accordance with ASTM C 117 and ASTM C 136.  The final
gradation shall be continuously well graded from coarse to fine and
shall not vary from the low limit on one sieve to the high limit on an
adjacent sieve or vice versa.

**TABLE 1. REQUIREMENTS FOR GRADATION OF AGGREGATE \\1\\**

+---------------------+------------------------+----------------------+
| **Sieve Size**      | **Design Range**       | **Job Mix            |
|                     |                        | Tolerances**         |
|                     | **Percentage by        |                      |
|                     | Weight**               | **Percent**          |
|                     |                        |                      |
|                     | **Percentage by        |                      |
|                     | Weight**               |                      |
+---------------------+------------------------+----------------------+
| 2 in (50.0 mm)      | 100                    | 0                    |
+---------------------+------------------------+----------------------+
| 1-1/2 (37.0 mm)     | 95-100                 | +/- 5                |
+---------------------+------------------------+----------------------+
| 1 in (25.0 mm)      | 70-95                  | +/- 8                |
+---------------------+------------------------+----------------------+
| 3/4 in (19.0 mm)    | 55-85                  | +/‑ 8                |
+---------------------+------------------------+----------------------+
| No. 4 (4.75 mm)     | 30-60                  | +/‑ 8                |
+---------------------+------------------------+----------------------+
| No. 30 (0.60 mm)    | 12-30                  | +/‑ 5                |
+---------------------+------------------------+----------------------+
| No. 200 (0.075 mm)  | 0-8                    | +/‑ 3                |
+---------------------+------------------------+----------------------+

\\1\\ Where environmental conditions (temperature and availability of
free moisture) indicate potential damage due to frost action, the
maximum percent of material, by weight, of particles smaller than 0.02
mm shall be 3 percent when tested in accordance with ASTM D 422.  It
also may be necessary to have a lower percentage of material passing the
No. 200 sieve to help control the percentage of particles smaller than
0.02 mm maximum limit of 5 percent is recommended).

The job mix tolerances in Table 1 shall be applied to the job mix
gradation to establish a job control grading band.  The full tolerance
still will apply if application of the tolerances results in a job
control grading band outside the design range.

The fraction of the final mixture that passes the No. 200 (0.075 mm)
sieve shall not exceed 60 percent of the fraction passing the No. 30
(0.60 mm) sieve.

CONSTRUCTION METHODS

**209-3.1 PREPARING UNDERLYING COURSE**.  The underlying course shall be
checked and accepted by the Engineer before placing and spreading
operations are started.  Any ruts or soft yielding places caused by
improper drainage conditions, hauling, or any other cause shall be
corrected at the Contractor\'s expense before the base course is placed
thereon.  Material shall not be placed on frozen subgrade.

**209-3.2 MIXING**. The aggregate shall be uniformly blended during
crushing operations or mixed in a plant.  The plant shall blend and mix
the materials to meet the specifications and to secure the proper
moisture content for compaction.

**209-3.3 PLACING**.  The crushed aggregate base material shall be
placed on the moistened subgrade in layers of uniform thickness with a
mechanical spreader.

The maximum depth of a compacted layer shall be 6 inches (150 mm).  If
the total depth of the compacted material is more than 6 inches (150
mm), it shall be constructed in two or more layers.  In multi-layer
construction, the base course shall be placed in approximately
equal-depth layers.

The previously constructed layer should be cleaned of loose and foreign
material prior to placing the next layer.  The surface of the compacted
material shall be kept moist until covered with the next layer.

**209-3.4 COMPACTION**.  Immediately upon completion of the spreading
operations, the crushed aggregate shall be thoroughly compacted.  The
number, type, and weight of rollers shall be sufficient to compact the
material to the required density.

The moisture content of the material during placing operations shall not
be below, nor more than 2 percentage points above, the optimum moisture
content as determined by ASTM **\[ \]**.

**209-3.5 ACCEPTANCE SAMPLING AND TESTING FOR DENSITY**.  Aggregate base
course shall be accepted for density on a lot basis.  A lot will consist
of one day\'s production where it is not expected to exceed 2400 square
yards (2000 square meters).  A lot will consist of one-half day\'s
production where a day\'s production is expected to consist of between
2400 and 4800 square yards (2000 and 4000 square meters).

Each lot shall be divided into two equal sublots.  One test shall be
made for each sublot.  Sampling locations will be determined by the
Engineer on a random basis in accordance with statistical procedures
contained in ASTM D 3665.

Each lot will be accepted for density when the field density is at least
100 percent of the maximum density of laboratory specimens prepared from
samples of the base course material delivered to the job site.  The
specimens shall be compacted and tested in accordance with ASTM **\[
\]**.  The in-place field density shall be determined in accordance with
ASTM D 1556 or D 2167.  If the specified density is not attained, the
entire lot shall be reworked and/or recompacted and two additional
random tests made.  This procedure shall be followed until the specified
density is reached.

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> **The Engineer shall specify ASTM D 698 for areas designated for
> aircraft with gross weights of 60,000 pounds (27 200 kg) or less and
> ASTM D 1557 for areas designated for aircraft with gross weights
> greater than 60,000 pounds (27 200 kg).**

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

In lieu of the core method of field density determination, acceptance
testing may be accomplished using a nuclear gage in accordance with ASTM
D 2922 and ASTM D 3017.  The gage should be field calibrated in
accordance with paragraph 4 of ASTM D 2922.  Calibration tests shall be
conducted on the first lot of material placed that meets the density
requirements.

Use of ASTM D 2922 results in a wet unit weight, and when using this
method, ASTM D 3017 shall be used to determine the moisture content of
the material.  Calibration and Standardization shall be conducted in
accordance with ASTM standards.

If a nuclear gage is used for density determination, two random readings
shall be made for each sublot.

**209-3.6 FINISHING**.  The surface of the aggregate base course shall
be finished by blading or with automated equipment especially designed
for this purpose.

In no case will the addition of thin layers of material be added to the
top layer of base course to meet grade.  If the elevation of the top
layer is 1/2 inch (12 mm) or more below grade, the top layer of base
shall be scarified to a depth of at least 3 inches (75 mm), new material
added, and the layer shall be blended and recompacted to bring it to
grade.  If the finished surface is above plan grade, it shall be cut
back to grade and rerolled.

**209-3.7 SURFACE TOLERANCES**.  The finished surface shall not vary
more than 3/8 inch (9 mm) when tested with a 16-foot (4.8 m)
straightedge applied parallel with or at right angles to the
centerline.  Any deviation in excess of this amount shall be corrected
by the Contractor at the Contractor\'s expense.

**209-3.8 THICKNESS CONTROL**.  The completed thickness of the base
course shall be within 1/2 inch (12 mm) of the design thickness.  Four
determinations of thickness shall be made for each lot of material
placed.  The lot size shall be consistent with that specified in
paragraph 3.5.  Each lot shall be divided into four equal sublots.  One
test shall be made for each sublot.  Sampling locations will be
determined by the Engineer on a random basis in accordance with
procedures contained in ASTM D 3665.  Where the thickness is deficient
by more than 1/2 inch (12 mm), the Contractor shall correct such areas
at no additional cost by excavating to the required depth and replacing
with new material.  Additional test holes may be required to identify
the limits of deficient areas.

**209-3.9 MAINTENANCE**.  The base course shall be maintained in a
condition that will meet all specification requirements until the work
is accepted.  Equipment used in the construction of an adjoining section
may be routed over completed portions of the base course, provided no
damage results and provided that the equipment is routed over the full
width of the base course to avoid rutting or uneven compaction.

The Contractor shall remove all survey and grade hubs from the base
courses prior to placing any bituminous surface course.

METHOD OF MEASUREMENT

**209-4.1**  The quantity of crushed aggregate base course to be paid
for will be determined by measurement of the number of **\[square yards
(square meters)\]\[cubic yards (cubic meters)\]** of material actually
constructed and accepted by the Engineer as complying with the plans and
specifications.  **\[On individual depth measurements, thicknesses more
than 1/2 inch (12 mm) in excess of the design thickness shall be
considered as the specified thickness, plus 1/2 inch (12 mm) in
computing the number of cubic yards (cubic meters) for payment.\]**

BASIS OF PAYMENT

**209-5.1**  Payment shall be made at the contract unit price per
**\[square yard (square meter)\]\[cubic yard (cubic meter)\]** for
crushed aggregate base course.  This price shall be full compensation
for furnishing all materials, for preparing and placing these materials,
and for all labor, equipment tools, and incidentals necessary to
complete the item.

Payment will be made under:

Item P-209-5.1 Crushed Aggregate Base Course---per **\[square yard
(square meter\]\[cubic yard (cubic meter)\]**

TESTING REQUIREMENTS

ASTM C 29 Unit Weight of Aggregate

ASTM C 88 Soundness of Aggregates by Use of Sodium Sulfate

or Magnesium Sulfate

ASTM C 117 Materials Finer than 75μm (No. 200) Sieve in Mineral
Aggregates by Washing

ASTM C 131 Resistance to Degradation of Small-Size Coarse Aggregate by
abrasion and impact in the Los Angeles Machine

ASTM C 136 Sieve Analysis of Fine and Coarse Aggregates

ASTM D 75 Sampling Aggregate

ASTM D 422 Particle Size Analysis of Soils

ASTM D 693 Crushed Aggregate for Macadam Pavements

ASTM D 698 Moisture-Density Relations of Soils and Soil-Aggregate
Mixtures Using 5.5-lb (2.49-kg) Rammer and 12-in (305mm) Drop

ASTM D 1556 Density of Soil in Place by the Sand-Cone Method

ASTM D 1557 Test for Laboratory Compaction Characteristics of Soil Using
Modified Effort

ASTM D 2167 Density and Unit Weight of Soil in Place by the Rubber
Ballon Method

ASTM D 2419 Sand Equivalent Value of Soils and Fine Aggregate

ASTM D 2922 Density of Soil and Soil-Aggregate in Place by Nuclear
Methods

ASTM D 3017 Water Content of Soil and Rock in Place by Nuclear Methods

ASTM D 3665 Random Sampling of Construction Materials

ASTM D 4318 Liquid Limit, Plastic Limit, and Plasticity Index of Soils

**END OF P-209**

**Intentionally Left Blank**

### **ITEM P-210 CALICHE BASE COURSE**

DESCRIPTION

**210-1.1** This item shall consist of a base course composed of
caliche, caliche-gravel, caliche and limestone, or material of similar
characteristics, constructed on the prepared underlying course in
accordance with these specifications and in conformity to the dimensions
and typical cross section shown on the plans.

MATERIALS

**210-2.1 MATERIALS**.  The base course material shall consist of
caliche, caliche-gravel, caliche limestone, or similar materials
obtained from sources approved by the Engineer prior to use of the
materials.  All acceptable material shall be screened, and the oversize
shall be crushed and returned to the screened material in such manner
and proportions that will produce a uniform product.

The gradation of the material, as finally processed and blended, shall
meet the following requirements when tested in accordance with ASTM C
136.

Sieve Designation Percentage by Weight

(Square Openings) Passing Sieves

2 inch (50.0 mm) 100

No. 40 (0.425 mm) 15-35

No. 200 (0.075 mm) 0-15

That portion of the material, including the blended filler, passing a
No. 40 (0.425 mm) mesh sieve shall be known as soil binder and shall
have a liquid limit of not more than 35 and a plasticity index of not
more than 10 as determined as ASTM D 4318.

If necessary, the Contractor shall blend or combine materials so that
the final processed material meets all of the requirements of these
specifications.  The Contractor shall make such modifications in
materials and methods as are necessary to secure a material that is
capable of being compacted into a dense and well-bonded base.

**210-2.2 FILLER FOR BLENDING**.  If filler, in addition to that
naturally present in the base course material, is necessary for
satisfactory bonding of the material, for changing the soil constants of
the material passing the No. 40 mesh sieve, or for correcting the
gradation to the limitations of the specified gradation, it shall be
uniformly blended with the base course material on the runway, at the
crushing plant, or at the mixing plant.  The material for such purpose
shall be obtained from sources approved by the Engineer.

CONSTRUCTION METHODS

**210-3.1 OPERATION IN PITS**.  All work involved in clearing and
stripping pits, including the handling of unsuitable material, shall be
performed by the Contractor at his/her own expense.  The pits shall be
operated in such a manner that a clean and uniform material will be
secured.  The base course material shall be obtained from approved
sources.

**210-3.2 EQUIPMENT**.  All equipment necessary for the proper
construction of the work shall be on the project, in first-class working
condition, and approved by the Engineer before construction is permitted
to start.

**210-3.3 PREPARING UNDERLYING COURSE**.  The underlying course shall be
checked and accepted by the Engineer before placing and spreading
operations are started.  Any ruts or soft, yielding places caused by
improper drainage conditions, hauling, or any other cause, shall be
corrected at the Contractor\'s expense.

**210-3.4 PLACING AND SPREADING**

**a.**  The aggregate base material that has proportioned or processed
shall be placed on the prepared underlying course and compacted in
layers to the thickness shown on the plans.  The depositing and
spreading of the material shall commence where designated and shall
progress without breaks.  The material shall be deposited and spread in
lanes in a uniform layer and without segregation of size to such loose
depth that, when compacted, the layer shall have the required
thickness.  The base aggregate shall be spread by spreader boxes or
other approved devices that shall spread the aggregate in the required
amount.  The base material shall be spread and shaped the same day as
placed.

**b.**  If the travel plant method is used for mixing, the base material
shall be placed on the underlying course in windrows parallel to the
centerline of the runway.  Sufficient quantity and proportions of
materials shall be placed in the windrow to provide a base mixture
conforming to the specified grading and compacted thickness.  The
windrow shall be shaped to a uniform section and left undisturbed until
measuring and sampling are complete.  After mixing and before spreading,
the mixture shall be examined by the Engineer, who shall determine
whether the mixing is complete and satisfactory and whether the proper
moisture content is maintained for spreading.  No spreading shall be
done, except when authorized.

After the mixing has been completed, the base material shall be spread
to the required depth and width by a self-powered blade grader,
mechanical spreader, or other approved method.  In spreading, care shall
be taken to prevent cutting into the underlying layer. The material
shall be bladed, disced, and dragged if necessary until a smooth,
uniform surface is obtained true to line, grade, and cross section.

**c.**  When the base materials are to be proportioned and mixed or
blended in-place, the different layers shall be spread and placed as
follows with the relative proportions of the components of the mixture
designated by the Engineer.

The base aggregate shall be deposited and spread evenly to a uniform
thickness and width.  Then the binder or filler or other admixture shall
be deposited and spread evenly over the first layer.  As many layers of
materials as the Engineer may direct shall be added to obtain the
required base materials.

When the required materials have been placed, they shall be thoroughly
mixed and blended by means of approved graders, discs, harrows, or
rotary-tillers, supplemented by other suitable equipment, if necessary. 
The mixing shall continue until the mixture is uniform throughout. 
Areas of segregated material shall be corrected by the addition of
binder or filler material and shall be uniformly applied, prior to and
during the mixing operations if necessary, to maintain the material at
the proper moisture content.  When the mixing and blending have been
completed, the material shall be spread in a uniform layer which, when
compacted, will meet the requirements of thickness and typical cross
section.  Hauling over material that has not been mixed and shaped shall
not be permitted, except when necessitated by the placing of successive
layers of materials.  Layers of base material allowed to become
partially compacted shall be scarified and disced before placing binder
material or before blading and shaping for rolling.

**d.**  The base course shall be constructed in a layer not less than 3
inches (75 mm) nor more than 6 inches (150 mm) of compacted thickness. 
The aggregate, as spread, shall be of uniform grading with no pockets of
fine or coarse materials.  Unless otherwise permitted by the Engineer,
the aggregate shall not be spread more than 2,000 square yards (1700
square meters) in advance of the rolling.  Any necessary sprinkling
shall be kept within these limits.  No material shall be placed in snow
or on a soft, muddy, or frozen course.

When more than one layer is required, the construction procedure
described herein shall apply similarly to each layer.

During the placing and spreading, sufficient caution shall be exercised
to prevent the incorporation of subgrade, subbase, or shoulder material
in the base course mixture.

**210-3.5 COMPACTION**.  Immediately after completion of the spreading
operations, the mixture shall be thoroughly compacted.  The number,
type, and weight of rollers shall be sufficient to compact the mixture
to the required density.

The field density of the compacted material shall be at least 100
percent of the maximum density of laboratory specimens prepared from
samples of the material delivered to the jobsite.  The laboratory
specimens shall be compacted and tested in accordance with **\[ \]**. 
The in-place field density shall be determined in accordance with ASTM D
1556 or ASTM D 2167.  The moisture content of the material at the start
of compaction shall not be below nor more than 1-1/2 percentage points
above the optimum moisture content.

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

> **The Engineer shall specify ASTM D 698 for areas designated for
> aircraft with gross weights of 60,000 pounds (27 200 kg) or less and
> ASTM D 1557 for areas designated for aircraft with gross weights
> greater than 60,000 pounds (27 200 kg).**

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

> **If nuclear density machines are to be used for density
> determination, the machines shall be calibrated in accordance with
> ASTM D 2922. The nuclear equipment shall be calibrated using blocks of
> materials with densities that extend through a range representative of
> the density of the proposed base material. ASTM 3017 may be used to
> determine the moisture content of the material. (See Section 120 of
> the General Provisions for additional guidance)**

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

The course shall not be rolled when the underlying course is soft or
yielding or when the rolling causes undulation in the base course.  When
the rolling develops irregularities that exceed 3/8 inch (9 mm) when
tested with a 16-foot (4.8 m) straightedge, the irregular surface shall
be loosened, then refilled with the same kind of material as that used
in constructing the course, and again rolled as required above.

**210-3.6 FINISHING**.  The surface of the base course shall be finished
by blading or with automated equipment especially designed for this
purpose.

In no case will the addition of thin layers of material be added to the
top layer of base course to meet grade.  If the elevation of the top
layer is 1/2 inch (12 mm) or more below grade, the top layer of base
shall be scarified to a depth of at least 3 inches (75 mm), new material
added, and the layer shall be blended and recompacted to bring it to
grade.  If the finished surface is above plan grade, it shall be cut
back to grade and rerolled.

**210-3.7 SURFACE TOLERANCE**.  After the course has been completely
compacted, the surface shall be tested for smoothness and accuracy of
grade and crown.  Any portion lacking the required smoothness or failing
in accuracy of grade or crown shall be scarified, reshaped, recompacted,
and otherwise manipulated as the Engineer may direct until the required
smoothness and accuracy are obtained.  The finished surface shall not
vary more than 3/8 inch (9 mm) from a 16-foot (4.8 m) straightedge when
applied to the surface parallel with, and at right angles to, the
centerline.

**210-3.8 THICKNESS CONTROL**.  The thickness of the base course shall
be determined by depth tests or cores taken at intervals in such manner
that each test shall represent no more than 300 square yards (250 square
meters).  Where the thickness is deficient by more than 1/2 inch (12
mm), the Contractor shall correct such areas at no additional cost by
excavating to the required depth and replacing with new material. 
Additional test holes may be required to identify the limits of
deficient areas.  The Contractor shall replace, at his/her expense, the
base material where borings have been taken for test purposes.

**210-3.9 PROTECTION**.  Work on the base course shall not be
accomplished during freezing temperatures nor when the subgrade is wet. 
When the aggregates contain frozen materials or when the underlying
course is frozen, the construction shall be stopped.

Hauling equipment may be routed over completed portions of the base
course, provided no damage results and provided that such equipment is
routed over the full width of the base course to avoid rutting or uneven
compaction.  However, the Engineer in charge shall have full and
specific authority to stop all hauling over completed or partially
completed base course when, in his/her opinion, such hauling is causing
damage.  Any damage resulting to the base course from routing equipment
over the base course shall be repaired by the Contractor at his/her own
expense.

**210-3.10 MAINTENANCE**.  Following the completion of the base course,
the Contractor shall perform all maintenance work necessary to keep the
base course in a condition satisfactory for priming.  After priming, the
surface shall be kept clean and free from foreign material.  The base
course shall be properly drained at all times.  If cleaning is
necessary, or if the prime coat becomes disturbed, any work or
restitution necessary shall be performed at the expense of the
Contractor.

METHOD OF MEASUREMENT

**210-4.1**  The quantity of caliche base course to be paid for shall be
the number of cubic yards (cubic meters) of base course material placed,
bonded, and accepted in the completed base course.  The quantity of base
course material shall be measured in final position, based upon depth
tests or cores taken as directed by the Engineer, at the rate of 1 depth
test for each 300 square yards (250 square meters) of base course, or by
means of average end areas on the complete work computed from elevations
to the nearest 0.01 foot (3 mm).  On individual depth measurements,
thickness more than 1/2 inch (12 mm) in excess of that shown on the
plans shall be considered as specified thickness, plus 1/2 inch (12 mm)
in computing the yardage for payment.  Base material shall not be
included in any other excavation quantities.

BASIS OF PAYMENT

**210-5.1**  Payment shall be made at the contract unit price per cubic
yard (cubic meter) for caliche base course.  This price shall be full
compensation for furnishing all materials and for all preparation,
hauling, and placing of these materials, and for all labor, equipment,
tools, and incidentals necessary to complete the item.

Payment will be made under:

Item P-210-5.1 Caliche Base Course---per cubic yard (cubic meter)

TESTING REQUIREMENTS

ASTM C 136 Sieve Analysis of Fine and Coarse Aggregates

ASTM D 698 Moisture-Density Relations of Soils and Soil-Aggregate
Mixtures Using 5.5 lb (2.49 kg) Rammer and 12-in. (305 mm) Drop

ASTM D 1557 Test for Laboratory Compaction Characteristics of Soil Using
Modified Effort

ASTM D 4318 Liquid Limit, Plastic Limit, and Plasticity Index of Soils

END OF ITEM P-210

### **ITEM P-211 LIME ROCK BASE COURSE**

DESCRIPTION

**211-1.1**  This item shall consist of a base course composed of lime
rock constructed on the prepared underlying course in accordance with
these specifications and shall conform to the dimensions and typical
cross section shown on the plans.

MATERIALS

**211-2.1 MATERIALS**.  The lime rock base course material shall consist
of fossiliferous limestone of uniform quality, and shall not contain
hard or flinty pieces that will cause a rough surface containing pits
and pockets.  The rock shall show no tendency to \`\`air slake\'\' or
undergo chemical change when exposed to the weather. The material when
watered and rolled shall be capable of being compacted into a dense and
well-bonded base.

The oolitic type of lime rock shall meet the following requirements:

Carbonates of calcium and magnesium - not less than 70%. 

Oxides of iron and aluminum - not more than 2%. 

The combined amount of carbonates, oxides, and silica shall be at least
97%.  The material shall be non-plastic.

All other types of lime rock shall contain not less than 95% of
carbonates of calcium and magnesium.  Liquid limit shall not exceed 35,
plasticity index shall not exceed 6, as determined in accordance with
ASTM D 4318.

The chemical analysis of lime rock shall consist of determining the
insoluble silica, iron oxide, and alumina by solution of the sample in
hydrochloric (HCl) acid, evaporating, dehydrating, redissolving the
residue, and neutralizing with ammonium hydroxide, filtering, washing,
and igniting the residue lime rock.  The difference between the
percentage of insoluble matter and 100% is reported as carbonates of
calcium and magnesium.

The lime rock shall not contain more than 0.5% of roots, leaf mold,
organic, or foreign matter and shall be obtained from pits from which
all overburden has been removed previous to blasting and quarrying.

The gradation of the lime rock shall meet the following requirements:  

Sieve Designation Percentage by Weight

(square openings) Passing Sieves

3‑1/2 inch (90.mm) 100

3/4 inch (19.0 mm) 50-100

All fine material shall consist entirely of dust of fracture.

CONSTRUCTION METHODS

**211-3.1 SOURCES OF SUPPLY**.  All work involved in cleaning and
stripping pits, including the handling of unsuitable material shall be
performed by the Contractor at his/her own expense.  The lime rock shall
be obtained from approved sources.  The pits shall be operated in such a
manner that a clean and uniform material will be secured.

**211-3.2 EQUIPMENT**.  All equipment necessary for the proper
construction of this work shall be on the project, in first-class
working condition, and approved by the Engineer before construction is
permitted to start.

**211-3.3 PREPARING UNDERLYING COURSE**.  The underlying course shall be
checked and accepted by the Engineer before placing and spreading
operations are started.  Any ruts or soft yielding places caused by
improper drainage conditions, hauling, or any other cause shall be
corrected at the Contractor\'s expense before the base course is placed
thereon. Material shall not be placed on frozen subgrade.

**211-3.4 PLACING AND SPREADING**.  All base course material shall be
placed on the prepared underlying course and compacted in layers to the
thickness shown on the plans.  The depositing and spreading of the
material on the prepared course or on a completed layer shall commence
where designated and shall progress without breaks.  The material shall
be deposited and spread in lanes in a uniform layer and without
segregation of size to such loose depth that, when compacted, the layer
shall have the required thickness.  When more than one layer is
required, the construction procedure described herein shall apply
similarly to each layer, excepting the scarifying and rerolling of the
surface which shall apply to only the top layer.

The rock shall be transported to locations where it is to be used over
rock previously placed and dumped at the end of the preceding spread. 
It shall then be spread uniformly with shovels, forks, or approved
mechanical spreaders especially constructed for this purpose.  In no
case shall rock be dumped directly onto the underlying course. 
Transporting over the underlying course will not be permitted, except as
directed, in which case it must be protected by planking if rutting
occurs.  During the dumping and spreading operations, the rock shall be
brought to the proper moisture content to obtain maximum density.  If
water is added, it shall be uniformly mixed to the full depth of the
course by discing.  All segregated areas of fine or coarse rock shall be
removed and replaced with well-graded rock, and approved by the
Engineer.  Lime rock shall not be spread when the subgrade is in an
unsuitable condition.

The lime rock base course shall be constructed in a layer not less than
4 inches (100 mm) nor more than 6 inches (150 mm) of compacted
thickness.  The base course shall be constructed in lanes or strips
parallel with the centerline of the paved area.

During the placing operation, sufficient caution shall be exercised to
prevent the incorporation of subgrade, subbase, or shoulder material in
the lime rock.

**211-3.5 ROLLING**.  Immediately after completion of the spreading
operations, the base material shall be thoroughly compacted.  The
number, type, and weight of rollers shall be sufficient to compact the
mixture to the required density.

The field density of the compacted material shall be at least 100
percent of the maximum density of laboratory specimens prepared from
samples of the base material delivered to the jobsite.  The laboratory
specimens shall be compacted and tested in accordance with **\[ \]**. 
The in-place field density shall be determined in accordance with ASTM D
1556.  The moisture content of the material at the start of compaction
shall not be below nor more than 1-1/2 percentage points above the
optimum moisture content.

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

> **The Engineer shall specify ASTM D 698 for areas designated for
> aircraft with gross weights of 60,000 pounds (27 200 kg) or less and
> ASTM D 1557 for areas designated for aircraft with gross weights
> greater than 60,000 pounds (27 200 kg).**

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

**211-3.6 FINISHING BASE COURSE**.  After the watering and rolling of
the base course, the entire surface shall be scarified to a depth of at
least 3 inches (75 mm) and shaped to the exact crown and cross section
with a blade grader.  The scarified material shall be rewatered and
thoroughly rolled.  Rolling shall continue until the base is bonded and
compacted into a dense, unyielding mass, true to grade and cross
section.  The scarifying and rolling of the surface of the base shall
follow the initial rolling of the lime rock by not more than 4 days. 
When the lime rock base is constructed in two layers, the scarifying of
the surface shall be to a depth of 2 inches (50 mm).

If, in the opinion of the Engineer, the surface of the base is glazed or
cemented to the extent that the prime coat could not penetrate properly,
and after determining that the condition of the base meets all
requirements, he will direct that the surface of the base be hard-planed
with a blade grader and broomed immediately prior to the application of
the prime coat.  This hard-planing shall be done in such a manner that
only the glazed or cemented surface is removed, leaving a granular or
porous condition that will allow free penetration of the prime material.
The material planed from the base shall be removed from the base area.

If at any time the underlying material becomes churned up and mixed with
the base course material, the Contractor shall, without additional
compensation, dig out and remove the mixture, reshape and compact the
underlying course, and replace the materials removed with clean rock
which shall be watered and rolled until satisfactorily compacted.

Where cracks, checks, or failures appear in the base, either before or
after priming and before the surface course is laid, the Contractor
shall remove such cracks, checks, or failures by rescarifying,
reshaping, watering, rolling, and adding lime rock where necessary.

**211-3.7 SURFACE TOLERANCE**.  After the course has been completely
compacted, the surface shall be tested for smoothness and accuracy of
grade and crown.  Any portion lacking the required smoothness or failing
in accuracy of grade or crown shall be scarified, reshaped, recompacted,
and otherwise manipulated as the Engineer may direct until the required
smoothness and accuracy are obtained.  The finished surface shall not
vary more than 3/8 inch (9 mm) from a 16-foot (4.8 mm) straightedge when
applied to the surface parallel with, and at right angles to, the
centerline.  In testing surface of the harder lime rocks, measurement of
clearances from the straightedge shall not include small holes caused by
individual pieces being pulled out by the grader.

**211-3.8 THICKNESS**.  The thickness of the base course shall be
determined by depth tests or elevations taken at intervals in such a
manner that each test shall represent 300 square yards (250 square
meters), or it shall be as otherwise directed by the Engineer.  The
depth tests shall be made by test holes through the base at least 3
inches (75 mm) in diameter.  Where the base deficiency is more than 1/2
inch (12 mm), the Contractor shall correct such areas by scarifying and
adding rock.  The base shall be scarified, rock added, and tapered a
distance of 100 feet (30 m) in each direction from the edge of the
deficient area for each inch of rock added.  The affected area shall
then be watered, bladed, rolled, and brought to a satisfactory state of
compaction, required thickness, and cross section.  The thickness of the
base in the affected area shall be remeasured by depth tests or
elevations.  The operations of scarifying, adding rock, and rerolling
shall continue until the base thickness is within the 1/2-inch (12 mm)
tolerance of base thickness.  The final base thickness of the
reconditioned area shall be used to determine the average job thickness.

The average job thickness shall be the average of the depth measurement
as above outlined and shall be within 1/4 inch (6 mm) of the thickness
shown on the typical cross section.  On individual depth measurements,
thicknesses more than 1/2 inch (12 mm) in excess of that shown on the
plans shall be considered as specified thickness plus 1/2 inch (12 mm)
in computing the average job thickness.  The Contractor shall replace,
at his/her expense, the lime rock removed from test holes.

**211-3.9 PROTECTION**.  Work on the base course shall not be
accomplished during freezing temperatures nor when the subgrade is wet. 
When the aggregate contains frozen materials or the underlying course is
frozen, the construction shall be stopped.

Hauling equipment may be routed over completed portions of the base
course, provided no damage results and provided that such equipment is
routed over the full width of the base course to avoid rutting or uneven
compaction.  However, the Engineer in charge shall have full and
specific authority to stop all hauling over completed or partially
completed base course when, in his/her opinion, such hauling is causing
damage.  Any damage resulting to the base course from routing equipment
over the base course shall be repaired by the Contractor at his/her own
expense.

**211-3.10 MAINTENANCE**.  Following the completion of the base course,
the Contractor shall perform all maintenance work necessary to keep the
base course in a condition satisfactory for priming.  After priming, the
surface shall be kept clean and free from foreign material.  The base
course shall be properly drained at all times.  If cleaning is
necessary, or if the prime coat becomes disturbed, any work or
restitution necessary shall be performed at the expense of the
Contractor.

METHOD OF MEASUREMENT

**211-4.1**  The quantity of lime rock base course to be paid for shall
be the number of cubic yards (cubic meters) of base material placed,
bonded, and accepted in the completed base course.  The quantity of base
course material shall be measured in final position, based upon depth
tests taken as directed by the Engineer, at the rate of 1 depth test for
each 300 square yards (250 square meters) of base course, or by means of
average end areas on the complete work computed from elevations to the
nearest 0.01 foot (3 mm).  On individual depth measurements, thicknesses
more than 1/2 inch (12 mm) in excess of that shown on the plans shall be
considered as the specified thickness plus 1/2 inch (12 mm) in computing
the yardage for payment.

BASIS OF PAYMENT

**211-5.1**  Payment shall be made at the contract unit price per cubic
yard (cubic meter) for lime rock base course.  This price shall be full
compensation for furnishing all materials and for all preparation,
hauling, and placing of these materials, and for all labor, equipment,
tools, and incidentals necessary to complete the item.

The cost of removing cracks and checks including the labor and material
for repriming, and the additional lime rock necessary for crack
elimination, will not be paid for separately but shall be included in
the contract price per cubic yard (cubic meter) for lime rock base
course.

Payment will be made under:

Item P-211-5.1 Lime rock base course per cubic yard (cubic meter) 

TESTING REQUIREMENTS

ASTM C 136 Sieve Analysis of Fine and Coarse Aggregates

ASTM D 698 Moisture-Density Relations of Soils and Soil Aggregate
Mixtures Using 5.5-lb (2.49-kg) Rammer and 12-in (305 mm) Drop

ASTM D 1556 Density of Soil in Place by the Sand-Cone Method

ASTM D 1557 Test for Laboratory Compaction Characteristics of Soil Using
Modified Effort

ASTM D 4318 Liquid Limit, Plastic Limit, and Plasticity Index of Soils

END OF ITEM P-211

### **ITEM P-212 SHELL BASE COURSE**

DESCRIPTION

**212-1.1** This item shall consist of a base course composed of shell
and binder constructed on a prepared underlying course in accordance
with these specifications and shall conform to the dimensions and
typical cross section shown on the plans.

MATERIALS

**212-2.1 MATERIALS**.  The shell shall consist of durable particles of
\`\`dead\'\' oyster or clam shell.  The base material shall consist of
oyster shell, together with an approved binding or filler material,
blended or processed to produce a uniform mixture complying with the
specifications for gradation, soil constants, and compaction
capability.  Clam shell may be used only in combination with oyster
shell in the proportion up to and including 50%.

The shell shall be reasonably clean and free from excess amounts of clay
or organic matter such as leaves, grass, roots, and other objectionable
and foreign material.

The gradation of the blended or processed material shall meet the
requirements of the gradation given in the following table, when tested
in accordance with ASTM C 136.

Sieve Designation Percentage by Weight

(square openings) Passing Sieves

3 inch (75.0 mm) 100

3/4 inch (19.0 mm) 60-90

No. 4 (4.75 mm) 15-55

No. 200 (0.075 mm) 0-15

That portion of the material, including the blended filler, passing a
No. 40 (0.42 mm) mesh sieve shall be known as soil binder and shall have
a liquid limit of not more than 25 and a plasticity index of not more
than 8 as determined by ASTM D 4318.

If necessary, the Contractor shall blend or combine materials so that
the final processed material meets all the specifications.  The
Contractor shall make such modifications in materials and methods as are
necessary to secure a material that is capable of being compacted into a
dense and well-bonded base without an excess of soil binder.

**212-2.2 FILLER FOR BLENDING**.  If filler, in addition to that
naturally present in the base course material, is necessary for
satisfactory bonding of the material, or for changing the soil constants
of the material passing the No. 40 (0.42 mm) mesh sieve, or for
correcting the gradation to the limitations of the specified gradation,
it shall be uniformly blended with the base course material on the
pavement or at the plant.  The material for such purpose shall be
obtained from sources approved by the Engineer and shall be of a
gradation necessary to accomplish the specified gradation in the final
processed material.

CONSTRUCTION METHODS

**212-3.1 SOURCES OF SUPPLY**.  The Contractor shall notify the
Engineer, sufficiently in advance, of the intended source of supply of
shell.  the shell shall be obtained from approved sources.  The material
in the stockpile shall be handled in a manner that will secure a uniform
and satisfactory product.

**212-3.2 EQUIPMENT**.  All equipment necessary for the proper
construction of this work shall be on the project, in first-class
working condition, and approved by the Engineer before construction is
permitted to start.

The processing plant shall be designed, constructed, operated, and
capable of thoroughly mixing the shell, binder, and water in the
directed proportions to produce base material of the gradation and
consistency required.

**212-3.3 PREPARING UNDERLYING COURSE**.  The underlying course shall be
checked and accepted by the Engineer before placing and spreading
operations are started.  Any ruts or soft yielding places caused by
improper drainage conditions, hauling, or any other cause shall be
corrected at the Contractor\'s expense before the base course is placed
thereon.  Material shall not be placed on frozen subgrade or subbase.

**212-3.4 PLANT MIXING**.  The base material shall be uniformly blended
and mixed in an approved central or travel mixing plant.  The shell,
together with any blended material, shall be thoroughly mixed with the
required amount of water.  After the mixing is complete, the material
shall be transported to, or spread on, the underlying course without
undue loss of the moisture content.

**212-3.5 PLACING AND SPREADING**.  The base course material that is
correctly proportioned or that has been processed in a central plant
shall be placed on the prepared underlying course and compacted in the
thickness shown on the plans.  The depositing and spreading of the
material shall commence where designated and shall progress without
breaks.  The materials shall be deposited and spread in lanes in a
uniform layer and without segregation of size to such loose depth that,
when compacted, the layer shall have the required thickness.  The
material shall be spread by spreader boxes or other approved devices
that shall distribute the material in a uniform layer.  Dumping from
vehicles in piles requiring rehandling will not be permitted.  hauling
over the uncompacted base course shall not be permitted.

**212-3.6 TRAVEL PLANT MIX**.  When the use of a travel plant is
approved, sufficient quantities and proportions of all material
necessary shall be used to provide a base mixture that conforms to the
specified gradation, quality, and thickness.  If a windrow travel plant
is employed for mixing, the aggregate shall be placed in windrows
parallel to the pavement centerline. If a traveling plant is used which
mixes previously spread aggregates in-place, the material shall be
spread to a thickness that may be readily handled by the machine and
that will develop the proper thickness for each layer.  The base
material shall be of satisfactory moisture content to obtain maximum
density.

After the mixing has been completed, the base material shall be spread
to the required depth and width by a self-powered blade grader,
mechanical spreader, or other approved method.  In spreading, care shall
be taken to prevent cutting into the underlying layer.  The material
shall be bladed, disced, and dragged if necessary until a smooth,
uniform surface is obtained true to line, grade, and cross section and
in condition for compacting.

**212-3.7 MIXED IN-PLACE**.  When specified or permitted, the base
materials may be proportioned and mixed or blended in-place on the
underlying course.  the different layers shall be spread and placed in
the following manner with the relative proportions of the components of
the mixture designated by the Engineer.

The base aggregate shall be deposited and spread evenly on the subgrade
to a uniform thickness and width.  Then the binder or filler shall be
deposited and spread evenly over the first layer.  There shall be as
many layers of materials added as the Engineer may direct to obtain the
required base mixture.

After the required materials have been placed, they shall be thoroughly
mixed and blended using approved graders, discs, harrows, or
rotary-tillers, supplemented by other suitable equipment if necessary. 
The mixing shall continue until the mixture is uniform throughout. 
Areas of segregated material shall be corrected by the addition of
binder or filler material and then thoroughly remixed.  If necessary,
water in the required amount shall be uniformly applied as directed by
the Engineer prior to and during the mixing operations to maintain the
material at the proper moisture content.  When the mixing and blending
has been completed, the material shall be spread in a uniform layer
which, when compacted, will meet the requirements for thickness and
typical cross section.

**212-3.8 GENERAL METHODS FOR PLACING**.  The base course shall be
constructed in layers not less than 4 inches (100 mm) nor more than 6
inches (150 mm) of compacted thickness.  The aggregate, as spread, shall
be of uniform gradation with no pockets of fine or coarse materials. 
Unless otherwise permitted by the Engineer, the aggregate shall not be
spread more than 2,000 square yards (186 square meters) in advance of
the rolling.  Any necessary sprinkling shall be kept within this limit. 
No material shall be placed in snow or on a soft, muddy, or frozen
course.

When more than one layer is required, the construction procedure
described herein shall apply similarly to each layer.

The Engineer shall conduct tests to determine the maximum density and
the proper moisture content of the base material, and this information
will be available to the Contractor.  The base material shall be brought
to a satisfactory moisture content when rolling is started and any minor
variations prior to or during rolling shall be corrected by sprinkling
or aeration.

During placing and spreading operations, sufficient caution shall be
exercised to prevent the incorporation of subgrade, subbase, or shoulder
material into the base course mixture.

**212-3.9 COMPACTION**.  Immediately after completion of the spreading
operations, the base course shall be thoroughly compacted.  The number,
type, and weight of rollers shall be sufficient to compact the mixture
to the required density.

The field density of the compacted material shall be at least 100
percent of the maximum density of laboratory specimens prepared from
samples of the base material delivered to the jobsite.  The laboratory
specimens shall be compacted and tested in accordance with **\[ \]**. 
The in-place field density shall be determined in accordance with ASTM D
1556.  The moisture content of the material at the start of compaction
shall not be below nor more than 1-1/2 percentage points above the
optimum moisture content.

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

> **The Engineer shall specify ASTM D 698 for areas designated for
> aircraft with gross weights of 60,000 pounds (27 200 kg) or less and
> ASTM D 1557 for areas designated for aircraft with gross weights
> greater than 60,000 pounds (27 200 kg).**

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

**212-3.10 SURFACE TOLERANCE**.  After the course has been completely
compacted, the surface shall be tested for smoothness and accuracy of
grade and crown.  Any portion lacking the required smoothness of failing
in accuracy of grade or crown shall be scarified, reshaped, recompacted,
and otherwise manipulated as the Engineer may direct until the required
smoothness and accuracy are obtained.  The finished surface shall not
vary more than 3/8 inch (9 mm) from a 16-foot (4.8 m) straightedge when
applied to the surface parallel with, and at right angles to, the
centerline.

**212-3.11 THICKNESS**.  The thickness of the base course shall be
determined by depth tests or cores taken at intervals in such manner
that each test shall represent no more than 300 square yards (28 square
meters).  When the base deficiency is more than 1/2 inch (12 mm), the
Contractor shall correct such areas by scarifying, and replacing with
satisfactory materials, and then rolling, bonding, and refinishing in
accordance with these specifications.  The Contractor shall replace, at
his/her expense, the base material where borings have been taken for
test purposes.

**212-3.12 PROTECTION**.  Work on the base course shall not be
accomplished during freezing temperatures nor when the subgrade is wet. 
When the aggregates contain frozen materials or when the underlying
course is frozen, the construction shall be stopped.

Hauling equipment may be routed over completed portions of the base
course, provided no damage results and provided that such equipment is
routed over the full width of the base course, to avoid rutting or
uneven compaction.  However, the Engineer in charge shall have full and
specific authority to stop all hauling over completed or partially
completed base course when, in his/her opinion, such hauling is causing
damage.  Any damage resulting to the base course from routing equipment
over the base course shall be repaired by the Contractor at his/her own
expense.

**212-3.13 MAINTENANCE**.  Following the completion of the base course,
the Contractor shall perform all maintenance work necessary to keep the
base course in a condition satisfactory for priming.  After priming, the
surface shall be kept clean and free from foreign material.  The base
course shall be properly drained at all times.  If cleaning is necessary
or if the prime coat becomes disturbed, any work or restitution
necessary shall be performed at the expense of the Contractor.

METHOD OF MEASUREMENT

**212-4.1**  The quantity of shell base course to be paid for shall be
the number of cubic yards (cubic meters) of base course material placed,
bonded, and accepted in the completed base course.  The quantity of base
course material shall be measured in final position based upon depth
tests or cores taken as directed by the Engineer, at the rate of 1 depth
test for each 300 square yards (28 square meters) of base course, or by
means of average end areas on the complete work computed from elevations
to the nearest 0.01 foot (3 mm).  On individual depth measurements,
thicknesses more than 1/2 inch (12 mm) in excess of that shown on the
plans shall be considered as specified thickness, plus 1/2 inch (12 mm)
in computing the yardage for payment.  Base materials shall not be
included in any other excavation quantities.

BASIS OF PAYMENT

**212-5.1**  Payment shall be made at the contract unit price per cubic
yard (cubic meter) for shell base course.  This price shall be full
compensation for furnishing all materials and for all preparation,
hauling, and placing of these materials, and for all labor, equipment,
tools, and incidentals necessary to complete the item.

Payment will be made under:

Item P-212-5.1 Shell Base Course---per cubic yard (cubic meter)

TESTING REQUIREMENTS

ASTM C 136 Sieve Analysis of Fine and Coarse Aggregates

ASTM D 698 Moisture-Content Relations of Soils and Soil Aggregate
Mixtures Using 5.5-lb (2.49-kg) Rammer and 12-in (305 mm) Drop

ASTM D 1556 Density of Soil in Place by the Sand-Cone Method

ASTM D 1557 Test for Laboratory Compaction Characteristics of Soil Using
Modified Effort

ASTM D 4318 Liquid Limit, Plastic Limit, and Plasticity Index of Soils

END OF ITEM P-212

### **ITEM P-213 SAND-CLAY BASE COURSE**

DESCRIPTION

**213-1.1**  This item shall consist of a base course composed of
approved selected material, constructed on a prepared underlying course
in accordance with these specifications and shall conform to the
dimensions and typical cross section shown on the plans.

MATERIALS

**213-2.1 SAND-CLAY**.  The materials shall be a mixture of clay and
mineral aggregate.  This mixture shall consist of topsoil, sand-clay,
sand-clay gravel, disintegrated granite, or other approved selected
aggregate, and it shall contain sufficient binder material so blended or
processed as to produce a uniform mixture complying with the
requirements of these specifications.

The materials shall be uniform and free from excess amounts of clay or  
organic matter such as leaves, grass, roots, and other objectionable or
foreign substances.  The coarse aggregate (particles coarser than a No.
4 mesh (4.75 mm) sieve) shall consist of hard, durable pieces or
fragments of stone or gravel.

The gradation of the blended or processed material shall meet the
requirements of one of the gradations given in the following table, when
tested in accordance with ASTM C 136.

Percentage by Weight

Sieve designation Passing Sieves

1-1/2 inch (38.5 mm) 100 100

1 inch (25.0 mm) 85-100 85-100

No. 4 (4.75 mm) 45-75 65-100

No. 10 (2.0 mm) 30-60 60-100

No. 40 (0.42 mm) 10-40 20-70

No. 200 (0.075 mm) 2-15 4-25

The fraction passing the No. 40 (0.42 mm) mesh sieve shall be referred
to as binder.  The fraction passing the No. 200 (0.075 mm) mesh sieve
shall be less than one-half the fraction passing the No. 40 (0.42 mm)
mesh sieve.  The material passing the No. 40 mesh sieve shall have a
plasticity index not to exceed 6 and have a liquid limit of not more
than 25, when tested in accordance with ASTM D 4318, for gradation A;
plasticity index shall not exceed 4 and the liquid limit shall not
exceed 25 for gradation B.

**213-2.2 FILLER FOR BLENDING**.  If filler, in addition to that
naturally present in the base course material, is necessary for
satisfactory bonding of the material, or for changing the soil constants
of the material passing the No. 40 (0.42 mm) mesh sieve, or for
correcting the gradation to the limitations of the specified gradation,
it shall be uniformly blended with the base course material.  The
material for such purpose shall be obtained from sources approved by the
Engineer and, when used, shall be of a gradation necessary to accomplish
the specified gradation in the finally processed material.

CONSTRUCTION METHODS

**213-3.1 OPERATION IN PITS**.  All work involved in clearing and
stripping pits, including the handling of unsuitable material shall be
performed by the Contractor at his/her expense.  The base material shall
be obtained from approved pits or other approved sources.  The material
in the pits shall be excavated and handled in a manner that assures a
uniform and satisfactory product.

**213-3.2 EQUIPMENT**.  All equipment necessary for the proper
construction of this work shall be on the project, in first-class
working condition, and approved by the Engineer before construction is
permitted to start.

The processing equipment shall be designed, constructed, operated, and
capable of thoroughly mixing all materials and water in the directed
proportions to produce a base course of the gradation and consistency
required.

**213-3.3 PREPARING UNDERLYING COURSE**.  The underlying course shall be
checked and accepted by the Engineer before placing and spreading
operations are started.  Any ruts or soft yielding places caused by
improper drainage conditions, hauling, or any other cause shall be
corrected at the Contractor\'s expense before the base course is placed
thereon.  Material shall not be placed on frozen subgrade or subbase.

**213-3.4 PLANT MIXING**.  The base material shall be uniformly blended
and mixed in an approved central or travel mixing plant.  The sand-clay,
together with any blended material, shall be thoroughly mixed with the
required amount of water. After the mixing is complete, the base
material shall be transported to, and spread on, the underlying course
without undue loss of the moisture content.

**213-3.5 PLACING AND SPREADING**.  The base course material that is
correctly proportioned or that has been processed in a plant shall be
placed on the prepared underlying course and compacted in the thickness
shown on the plans.  The depositing and spreading of the material shall
commence where designated and shall progress without breaks.  The
material shall be deposited and spread in lanes in a uniform layer and
without segregation of size to such loose depth that, when compacted,
the layer shall have the required thickness.  The material shall be
spread by spreader boxes, or other approved devices, equipped to
distribute the material in a uniform layer.

When approved, the material may be dumped in piles, but it shall be
spread immediately.  Hauling over the uncompacted base course shall not
be permitted.

**213-3.6 TRAVEL PLANT MIX**.  When the use of a travel plant is
approved, sufficient quantities and proportions of all material
necessary shall be used to provide a base mixture that conforms to the
specified gradation, quality, and thickness.  If a windrow travel plant
is employed for mixing, the sand-clay shall be placed in windrows
parallel to the pavement centerline.  If a traveling plant is used which
mixes previously spread material in-place, the sand-clay shall be spread
to a thickness that may be readily handled by the machine and that will
develop the proper thickness for each layer.  The base material shall be
of a satisfactory moisture content to obtain maximum density.

After mixing has been completed, the base material shall be spread to
the required depth and width by a self-powered blade grader, mechanical
spreader, or other approved method.  In spreading, care shall be taken
to prevent cutting into the underlying layer.  The material shall be
bladed, disced, and dragged if necessary until a smooth, uniform surface
is obtained true to line, grade, and cross section and in condition for
compacting.

**213-3.7 MIXED IN-PLACE**.  When the base materials are to be
proportioned and mixed or blended in-place, the different layers shall
be spread and placed in the following manner with the relative
proportions of the components of the mixture designated by the Engineer.

The base aggregate shall be deposited and spread evenly on the subgrade
to a uniform thickness and width.  Then the binder or filler shall be
deposited and spread evenly over the first layer.  There shall be as
many layers of materials added as the Engineer may direct to obtain the
required base mixture.

After the required materials have been placed, they shall be thoroughly
mixed and blended using approved graders, discs, harrows,
rotary-tillers, supplemented by other suitable equipment if necessary. 
The mixing shall continue until the mixture is uniform throughout. 
Areas of segregated material shall be corrected by the addition of
binder or filler material and then thoroughly remixed.  If necessary,
water in the required amount shall be uniformly applied as directed by
the Engineer prior to and during the mixing operation to maintain the
material at the proper moisture content.  When the mixing and blending
has been completed, the material shall be spread in a uniform layer
which, when compacted, will meet the requirements for thickness and
typical cross section.

**213-3.8 GENERAL METHODS FOR PLACING**.  The base course shall be
constructed in layers not less than 4 inches (100 mm) nor more than 6
inches (150 mm) of compacted thickness.  Each layer shall be measured
for depth.  The material, as spread, shall be of uniform gradation with
no pockets of fine or coarse materials.  Unless otherwise permitted by
the Engineer, the base shall not be spread more than 2,000 square yards
(186 square meters) in advance of the rolling.  Any necessary sprinkling
shall be kept within this limit. No material shall be placed in snow or
on a soft, muddy, or frozen course.

When more than one layer is required, the construction procedure
described herein shall apply similarly to each layer.

During placing and spreading operations, sufficient caution shall be
exercised to prevent the incorporation of subgrade, subbase, or shoulder
material into the base course mixture.

**213-3.9 COMPACTION**.  Immediately after completion of the spreading
operations, the base material shall be thoroughly compacted.  The
number, type, and weight of rollers shall be sufficient to compact the
mixture to the required density.

The field density of the compacted material shall be at least 100
percent of the maximum density of laboratory specimens prepared from
samples of the base material delivered to the jobsite.  The laboratory
specimens shall be compacted and tested in accordance with **\[ \]**. 
The in-place field density shall be determined in accordance with ASTM D
1556.  The moisture content of the material at the start of compaction
shall not be below nor more than 1-1/2 percentage points above the
optimum moisture content.

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

> **The Engineer shall specify ASTM D 698 for areas designated for
> aircraft with gross weights of 60,000 pounds (27 200 kg) or less and
> ASTM D 1557 for areas designated for aircraft with gross weights
> greater than 60,000 pounds (27 200 kg).**

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

**213-3.10 SURFACE TOLERANCE**.  After the course has been completely
compacted, the surface shall be tested for smoothness and accuracy of
grade and crown.  Any portion lacking the required smoothness or failing
in accuracy of grade or crown shall be scarified, reshaped, recompacted,
and otherwise manipulated as the Engineer may direct until the required
smoothness and accuracy are obtained.  The finished surface shall not
vary more than 3/8 inch (9 mm) from a 16-foot (4.8 mm) straightedge when
applied to the surface parallel with, and at right angles to, the
centerline.

**213-3.11 THICKNESS**.  The thickness of the base course shall be
determined by depth tests or cores taken at intervals in such manner
that each test shall represent no more than 300 square yards (28 square
meters).  When the base deficiency is more than 1/2 inch (12 mm), the
Contractor shall correct such areas by scarifying, adding satisfactory
base mixture, rolling, sprinkling, reshaping, and refinishing in
accordance with these specifications.  The Contractor shall replace, at
his/her expense, the base material where borings have been taken for
test purposes.

**213-3.12 PROTECTION**.  Work on the base course shall not be
accomplished during freezing temperature nor when the subgrade is wet. 
When the base material contains frozen material or when the underlying
course is frozen, the construction shall be stopped.

Hauling equipment may be routed over completed portions of the base
course, provided no damage results and provided that such equipment is
routed over the full width of the base course to avoid rutting or uneven
compaction.  However, the Engineer in charge shall have fall and
specific authority to stop all hauling over completed or partially
completed base course when, in his/her opinion, such hauling is causing
damage.  Any damage resulting to the base course from routing equipment
over the base course shall be repaired by the Contractor at his/her own
expense.

**213-3.13 MAINTENANCE**.  Following the completion of the base course,
the Contractor shall perform all maintenance work necessary to keep the
base course in a condition satisfactory for priming.  After priming, the
surface shall be kept clean and free from foreign material.  The base
course shall be properly drained at all times.  If cleaning is
necessary, or if the prime coat becomes disturbed, any work or
restitution necessary shall be performed at the expense of the
Contractor.

METHOD OF MEASUREMENT

**213-4.1**  The quantity of sand-clay base course to be paid for shall
be the number of cubic yards (cubic meters) of base course material
placed, bonded, and accepted in the completed base course.  The quantity
of base course material shall be measured in final position based upon
depth tests or cores taken as directed by the Engineer, at the rate of 1
depth test for each 300 square yards (28 square meters) of base course,
or by means of average end areas on the complete work computed from
elevations to the nearest 0.01 foot (3 mm).  On individual depth
measurements, thicknesses more than 1/2 inch (12 mm) in excess of that
shown on the plans shall be considered as the specified thickness, plus
1/2 inch (12 mm) in computing the yardage for payment.  Base materials
shall not be included in any other excavation quantities.

BASIS OF PAYMENT

**213-5.1**  Payment shall be made at the contract unit price per cubic
yard (cubic meter) for sand-clay base course.  This price shall be full
compensation for furnishing all materials and for all preparation,
hauling, and placing of these materials, and for all labor, equipment,
tools, and incidentals necessary to complete the item.

Payment will be made under:

Item P-213-5.1 Sand-Clay Base Course---per cubic yard (cubic meter)

TESTING REQUIREMENTS

ASTM C 136 Sieve Analysis of Fine and Coarse Aggregates

ASTM D 698 Moisture-Density Relations of Soils and Soil Aggregate
Mixtures Using 5.5-lb (2.49-kg) Rammer and 12-in (305 mm) Drop

ASTM D 1556 Density of Soil in Place by the Sand-Cone Method

ASTM D 1557 Test for Laboratory Compaction Characteristics of Soil Using
Modified Effort

ASTM D 2167 Density and Unit Weight of Soil in Place by the Rubber
Ballon Method

ASTM D 4318 Liquid Limit, Plastic Limit, and Plasticity Index of Soils

END OF ITEM P-213

### **ITEM P-217 AGGREGATE-TURF PAVEMENT**

DESCRIPTION

**217-1.1**  This item shall consist of an aggregate-turf pavement
composed of a base course of soil-bound crushed stone, soil-bound
gravel, or soil-bound sand, and a seedbed of suitable soil or
combination of soil and aggregate, constructed on a prepared subgrade or
a previously constructed underlying course in accordance with these
specifications, and shall conform to the dimensions and typical cross
section shown on the plans.

This item may include the furnishing and applying of fertilizer, lime,
top-soil, or other plant nutrients; the furnishing and planting of seed;
and the furnishing and spreading of mulch.  When any of these turfing
materials are required, the quality, quantity, and construction methods
shall be in accordance with applicable FAA Turf Specifications.  When
turf is to be established, the seedbed soil or topsoil shall be a
natural friable soil, possessing characteristics of the best locally
obtainable soils, which can produce a fairly heavy growth of crops,
grass, or other vegetation.

The prepared composite mixture of aggregates used for the base course
shall be **\[Type A, B, or C, of Table 1\]\[stabilizer aggregate of
Table 2 mixed with in-place materials\]**.

MATERIALS

**217-2.1 STABILIZED MIXES**.  The designated stabilized base course
mixtures shall conform to the following requirements.

Type A -- The materials shall be natural or artificial mixtures of clay
or soil binder and gravel, stone or sand, as screenings proportioned to
meet the requirements specified.

Type B or C -- The materials shall be natural or artificial mixtures of
gravel, stone, or slag and soil so proportioned as to meet the
requirement specified. The aggregate shall consist of clean, hard
durable particles of crushed or uncrushed gravel, stone, or slag, and
shall be free from soft, thin, elongated, or laminated pieces, and
vegetable or other deleterious substances.

The prepared composite mixture used shall meet one of the applicable
gradation requirements as follows when tested in accordance with ASTM C
136.

**TABLE 1. REQUIREMENTS FOR GRADATION OF MIXTURE**

  ------------------------- --------------- --------------- -------------
  **Sieve Designation**     **Percentage by                 
                            weight passing                  
                            sieves**                        

  **(square openings)**     **A**           **B**           **C**

  2 inch (50.0 mm)          0               0               100

  1 inch (24.0 mm)          100             100             70-95

  3/4 inch (19.0 mm)        0               70-100          

  No. 4 (4.75 mm)           0               40-70           

  No. 10 (2.00 mm)          60-100          40-70           32-60

  No. 20 (.085 mm)          50-90           0               0

  No. 40 (0.425 mm)         40-75           20-45           20-40

  No. 200 (0.075 mm)        12-30           10-20           10-20
  ------------------------- --------------- --------------- -------------

The fraction of the composite mixture passing the No. 200 (0.075 mm)
mesh sieve shall be less than two-thirds of the fraction passing the No.
40 (0.425 mm) mesh sieve.  the fraction passing the No. 40 (0.425 mm)
mesh sieve shall have a liquid limit not greater than 30 and a
plasticity index not greater than 8 when tested in accordance with ASTM
D 4318.

**217-2.2 STABILIZER AGGREGATE**.  Stabilizer aggregate conforming to
one of the gradations specified in Table 2, when tested in accordance
with ASTM C 136, shall be placed upon the existing soil or base course
in the specified quantity per square yard (square meter).  The aggregate
shall be uniformly blended with the soil or base course material to the
depth required or as shown on the plans.  The aggregate shall consist of
crushed stone, crushed or uncrushed gravel, or crushed slag, and it
shall have a percent of wear not more than 60 at 500 revolutions as
determined by ASTM C 131.  The aggregate shall be free from soft, thin,
elongated, or laminated pieces, disintegrated material, or other
deleterious substances.

Where sand, as existing subgrade or base, requires stabilization, it
shall be secured by the addition of clay or lime rock.  The operations
of spreading and mixing shall be handled as stated under construction
methods.

**TABLE 2. REQUIREMENTS FOR GRADATION OF STABILIZER AGGREGATE**

  ------------------------- --------------- --------------- ---------------
  **Sieve designation**     **Percentage by                 
                            weight passing                  
                            sieves**                        

  **(square openings)**     **D**           **E**           **F**

  2 inch (50.0 mm)                          100             

  1‑1/2 inch (37.5 mm)      100                             

  1 inch (24.0 mm)          90-100                          

  1/2 inch (12.5 mm)                        0-15            100

  No. 4 (4.75 mm)           20-50                           85-100

  No. 10 (2.00 mm)          0-10                            

  No. 100 (0.150 mm)                                        0-30
  ------------------------- --------------- --------------- ---------------

CONSTRUCTION METHODS

**217-3.1 OPERATION IN PITS**.  All work involved in clearing and
stripping pits, including handling of unsuitable material, shall be
performed by the Contractor at his/her own expense.  The base or binder
material shall be obtained from approved sources.  The material in the
pits shall be excavated and handled in a manner that will secure a
uniform and satisfactory product.

**217-3.2 EQUIPMENT**.  All equipment necessary for the proper
construction of this work shall be on the project in first-class working
condition and approved by the Engineer before construction is permitted
to start.

**217-3.3 PREPARING SUBGRADE**.  Before any base course material is
placed, the subgrade or underlying course shall be prepared and
conditioned as specified.  The underlying course shall be checked and
accepted by the Engineer before placing and spreading operations are
started.

**217-3.4 PLACING MATERIALS**.

**a.**  All new material shall be placed on the prepared course and
compacted in layers of the thickness shown on the plans.  The depositing
and spreading of the material on the prepared and completed layer shall
commence where designated and shall progress without breaks.  The
material shall be deposited and spread in lanes in a uniform layer and
without segregation of size to such loose depth that, when compacted,
the layer will have the required thickness.  The material shall be
spread with approved equipment.  When it is necessary to combine
materials from different sources, it may be done either at the pits, in
a processing plant prior to delivery of the material, or on the course
in the proper proportions and in successive spreadings that give the
required gradation and thickness of layer.  If the combining is done on
the course, the mixing shall be as specified hereinafter.

**b.**  When it is necessary to blend new material with material on the
existing surface, the existing surface shall first be scarified lightly
and bladed to uniform grade and cross section as shown on the plans. 
After blading, and when necessary, the existing surface shall be further
scarified and/or pulverized to provide sufficient loose material of the
required depth to be mixed with the added material.

**217-3.5 SPREADING AND MIXING**.

**a.**  Materials that have been mixed and processed in a processing
plant at the pits, or elsewhere, shall be delivered and spread to the
required depth.

**b.**  Following the placing of the required materials being combined
on the base course, the total base material shall be thoroughly
pulverized and mixed by approved rotary-pulverizing mixers.  The
moisture content of the aggregate and soil binder shall be as specified
by the Engineer to secure thorough mixing and the required compaction. 
The mixing shall produce a homogeneous mass of the specified gradation
and soil characteristics to form a base course of the desired
qualities.  When the mixing is completed, the material shall be spread
in a uniform layer which, when compacted, shall meet the requirements
for thickness and typical cross section.

**217-3.6 ROLLING**.  Immediately after completion of the spreading
operations, the material shall be thoroughly compacted.  The number,
type, and weight of rollers shall be sufficient to compact the material
to the required density.

The field density of the compacted material shall be at least 90 percent
of the maximum density of laboratory specimens prepared from samples of
the subbase material taken from the material delivered to the jobsite. 
The laboratory specimens shall be compacted and tested in accordance
with ASTM D 698.  The in-place field density shall be determined in
accordance with ASTM D 1556 or ASTM D 2167.  The moisture content of the
material at the start of compaction shall not be below nor more than
1-1/2 percentage points above the optimum moisture content.

**217-3.7 SURFACE TEST, THICKNESS, AND MAINTENANCE**.  The surface shall
not deviate more than 1/2 inch (12 mm) when tested with a 16-foot (4.8
m) straightedge applied parallel with, and at right angles to, the
centerline.  Any deviation in excess of this amount shall be corrected
by loosening, adding, or removing material, reshaping, and recompacting.

The thickness of the base course shall be determined by depth tests or
cores taken at intervals in such manner that each test shall represent
not more than 500 square yards (418 square meters).  When the base
deficiency exceeds 1/2 inch (12 mm), it shall be corrected.  The
Contractor shall replace, at his/her expense, the base material where
borings have been taken for test purposes.

The surface of the base course shall be maintained and kept in a
well-drained condition until the construction of another course. 
Sprinkling, blading, and rolling shall be performed when necessary to
prevent the base material from becoming unbonded.

**217-3.8 TURF-SURFACING**.  Following the construction of the
soil-aggregate base, the Contractor shall prepare the seedbed for the
turf.  If topsoil is to be placed, the surface of the base course shall
be loosened slightly, as directed by the Engineer.  If seeding is to be
done without topsoiling, the surface of the base shall be loosened
sufficiently to prepare a seedbed.  This can be accomplished by discing,
harrowing, rotary-tilling, or other approved methods, and should be to a
depth not less than 1 inch (25 mm) nor greater than 3 inches (75 mm). 
Any topsoil shall be spread to the depth as required.  The seedbed
preparation, applying lime, fertilizer and water, seeding, rolling and
mulching, shall be performed in accordance with the specification
requirements.

METHOD OF MEASUREMENT

**217-4.1**.  Soil-aggregate base course shall be measured by the number
of cubic yards (cubic meters) of base course material placed, bonded,
and accepted in the completed base course.  The quantity shall be
measured in final position based on depth tests or cores, or by means of
average end areas on the completed work.

Stabilizer aggregate shall be measured by the number of cubic yards
(cubic meters) of aggregate furnished, placed, and accepted in the
completed base course.

When approved materials in-place are utilized in the base course, the
preparation and incorporation of other materials in the base mixture
shall be measured as a conditioning and mixing operation.  Conditioning
shall be measured by the number of square yards (square meters) of such
material prepared and incorporated in the mix, completed, and accepted.

**\[Topsoil shall be measured by the number of cubic yards (cubic
meters) of topsoil removed, placed, and spread in the accepted work.\]**

**\[Lime and fertilizer shall be measured by the number of tons (kg) or
100-pound (45.4 kg) sacks, of the quality specified in the bid schedule,
furnished, incorporated, and accepted.\]**

**\[Seeding shall be measured by the number of acres seeded, and
accepted.\]**

**\[Watering for planting shall be measured by the number of
1,000-gallon (4000 liters) units of water measured by an approved water
meter or in the vehicle at the point of delivery, furnished and applied
as specified or ordered.\]**

**\[Mulching shall be measured by the number of acres mulched, and
accepted.\]**

BASIS OF PAYMENT

**217‑5.1**   Payment shall be made at the contract unit price per cubic
yard (cubic meter) for soil-aggregate base course; at the contract unit
price per cubic yard (cubic meter) for stabilizer aggregate; at the
contract unit price per square yard (cubic meter) for conditioning
operation; at the contract unit price per cubic yard (square meter) for
topsoil; at the contract unit price per ton (kg) for lime; at the
contract unit price per ton (kg) for fertilizer; at the contract unit
price per acre for seeding; at the contract unit price per 1,000-gallon
(4000 liter) unit for watering; and at the contract unit price per acre
for mulching.  These prices shall be full compensation for furnishing
all materials and for all preparation, hauling, and placing of these
materials; and for all labor, equipment, tools, and incidentals
necessary to complete the item.

Payment will be made under:

Item P-217-5.1 Soil Aggregate Base Course---per cubic yard (cubic meter)

Item P-217-5.2 Stabilizer Aggregate---per cubic yard (cubic meter)

Item P-217-5.3 Conditioning Operation---per square yard (cubic meter)

Item P-217-5.4 Topsoil---per cubic yard (cubic meter)

Item P-217-5.5 Lime---per ton (kg)

Item P-217-5.6 Fertilizer---per ton (kg)

Item P-217-5.7 Seeding---per acre

Item P-217-5.8 Watering---per 1,000-gallon (4000 liter) unit

Item P-217-5.9 Mulching---per acre

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\* \* \* \* \* \* \* \* \* \* \* \* \* \***

> **The Engineer shall include only those items shown in the bid
> schedule.**

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\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

TESTING REQUIREMENTS

ASTM C 131 Resistance to Abrasion of Small Size Coarse Aggregate by Use
of the Los Angeles Machine

ASTM C 136 Sieve Analysis of Fine and Coarse Aggregates

ASTM D 698 Moisture-Density Relations of Soils and Soil-Aggregate
Mixtures Using 5.5 lb (2.49 kg) Rammer and 12-inch (300 mm) Drop

ASTM D 1556 Density of Soil in Place by the Sand-Cone Method

END OF ITEM P-217

**Intentionally Left Blank**

### **ITEM P-219 RECYCLED CONCRETE** 

### **AGGREGATE BASE COURSE**

DESCRIPTION

**219 -1.1** This item consists of a base course composed of recycled
concrete aggregate, crushed to meet a particular gradation, constructed
on a prepared course in accordance with these specifications and in
conformity to the dimensions and typical cross sections shown on the
plans.

### MATERIALS

**219-2.1 AGGREGATE.** Recycled concrete aggregate shall consist of
Portland cement concrete or other concrete containing pozzolanic binder
material. The recycled concrete material shall be free of reinforcing
steel, expansion material. Asphalt concrete overlays shall be removed
from the PCC surface prior to pavement removal and crushing. Also,
full-slab asphalt concrete panels (used as a replacement for a removed
PCC slab) shall be removed. An incidental amount of recycled asphalt
concrete pavement and other foreign material may be present in the
recycled concrete aggregate.

Recycled concrete aggregate for base course shall consist of at least 90
percent, by weight, Portland cement concrete, with the following
materials making up the remaining 10 percent:

Wood - 0.1 percent maximum

Brick, mica, schist, or other friable materials - 4 percent maximum

Asphalt concrete -- 10 percent maximum

Virgin aggregates may be added to meet the 90 percent minimum concrete
requirement

The percentage of wood, brick, mica, schist, other friable materials,
and asphalt concrete shall be determined by weighing that material
retained on the No. 4 sieve, and dividing by the total weight of
recycled concrete aggregate material retained on the No. 4 sieve.

Fine aggregate passing the No.4 (4.75-mm) sieve shall consist of fines
from the operation of crushing the recycled concrete aggregate. If
necessary, fine aggregate may be added to produce the correct gradation.
The fine aggregate shall be produced by crushing stone, gravel, slag, or
recycled concrete that meet the requirements for wear and soundness
specified for coarse aggregate.

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

**To the extent possible, recycled concrete aggregate should be produced
from distress-free (material related) concrete. Published literature and
limited laboratory testing have indicated that alkali-silica reactivity
(ASR) is not a concern for crushed aggregate base course. The pavement
designer should exercise due care in evaluating site conditions and
other factors to ensure the proper use of ASR prone PCC.**

**The engineer shall gather and analyze available information on the
history and performance of the ASR-distressed PCC to be used to
manufacture base material. The results of this investigation will
justify why this material will provide an acceptable level of safety,
economy, and durability. The designer is also advised to consult with
experts (geologists, concrete petrographers, materials engineers, etc.)
on the degree of reactivity of aggregates from the source(s) used to
construct the original PCC. All information including test results and
experts consulted should be documented in the pavement design report.**

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

**Recycled concrete aggregate shall not be used in locations with high
sulfate content soils (no more than 1 percent).**

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

The amount of flat and elongated particles in recycled concrete
aggregate shall not exceed 20 percent for the fraction retained on the
0.5 inch (13 mm) sieve nor 20 percent for the fraction passing the 0.5
inch (13 mm) sieve when tested in accordance with ASTM D 4791. A flat
particle is one having a ratio of width to thickness greater than 3; an
elongated particle is one having a ratio of length to width greater than
3.

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

**Recycled concrete aggregate shape depends on the characteristics of
the recycled concrete, plant type, and plant operation speed. A number
of trial batches may have to be produced before crushed recycled
concrete aggregate meeting the shape and gradation requirements is
produced.**

**\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

The percentage of wear shall not be greater than 45 percent when tested
in accordance with ASTM C 131. The sodium sulfate soundness test (ASTM C
88) requirement is waived for recycled concrete aggregate.

The fraction passing the No. 40 (0.42-mm) sieve shall have a liquid
limit no greater than 25 and a plasticity index of not more than 4 when
tested in accordance with ASTM D 4318. The fine aggregate shall have a
minimum sand equivalent value of 35 when tested in accordance with ASTM
D 2419.

**a. Sampling and Testing.** Recycled concrete aggregate samples for
preliminary testing shall be furnished by the Contractor prior to the
start of base construction. All tests for initial aggregate submittals
necessary to determine compliance with the specification requirements
will be made by the Engineer at no expense to the Contractor.

Samples of recycled concrete aggregate shall be furnished by the
Contractor at the start of production and at intervals during
production. The sampling points and intervals will be designated by the
Engineer. The samples will be the basis of approval of specific lots of
recycled concrete aggregate for the quality requirements.

Samples of recycled concrete aggregate to check gradation shall be taken
at least once daily. Sampling shall be in accordance with ASTM D 75, and
testing shall be in accordance with ASTM C 136 and C 117.

**b. Gradation Requirements.** The gradation (job mix) of the final
mixture shall fall within the design range indicated in Table 1, when
tested in accordance with ASTM C 117 and C 136. The final gradation
shall be continuously graded from coarse to fine and shall not vary from
the low limit on one sieve to the high limit on an adjacent sieve or
vice versa.

+----------------------------+--------------------+--------------------+
| **Table 1. Requirements    |                    |                    |
| for gradation of recycled  |                    |                    |
| concrete aggregate.**      |                    |                    |
+----------------------------+--------------------+--------------------+
| Sieve Size                 | Percentage by      | Job Mix Tolerances |
|                            | Weight             |                    |
|                            |                    | Percent            |
|                            | Passing Sieves     |                    |
+----------------------------+--------------------+--------------------+
| 2 in (50.8 mm)             | 100                | \--                |
+----------------------------+--------------------+--------------------+
| 1-1/2 (37.5 mm)            | 95 - 100           | +/- 5              |
+----------------------------+--------------------+--------------------+
| 1 in (25.0 mm)             | 70 - 95            | +/- 8              |
+----------------------------+--------------------+--------------------+
| 3/4 in (19.0 mm)           | 55 - 85            | +/- 8              |
+----------------------------+--------------------+--------------------+
| No.4 (4.75 mm)             | 30 - 60            | +/- 8              |
+----------------------------+--------------------+--------------------+
| No. 30 (0.60 mm)           | 12 - 30            | +/- 5              |
+----------------------------+--------------------+--------------------+
| No. 200 (0.075 mm)         | 0 - 5              | +/- 3              |
+----------------------------+--------------------+--------------------+

The job mix tolerances in Table 1 shall be applied to the job mix
gradation to establish a job control gradation band. The full tolerance
still will apply if application of the tolerances results in a job
control gradation band outside the design range.

### EQUIPMENT

**219-3.1 GENERAL.** All equipment necessary to mix, transport, place,
compact, and finish the recycled concrete aggregate base course shall be
furnished by the Contractor. The Contractor shall provide written
certification to the Engineer that all equipment meets the requirements
for this section. The equipment shall be inspected by the Engineer at
the job site prior to the start of I construction operations.

,

**219-3.2 MIXING EQUIPMENT.** Base course shall be thoroughly mixed in a
plant suitable for recycled concrete aggregate. The mixer shall be a
batch or continuous-flow type and shall be equipped with calibrated
metering and feeding device that introduce the aggregate and water into
the mixer in specified quantities. If necessary, a screening device
shall be installed to remove oversized material greater than 2 in (50
mm) from the recycled concrete aggregate feed.

Free access to the plant shall be provided to the Engineer at all times
for inspection of the plant\'s equipment and operation and for sampling
the mixed recycled concrete aggregate

materials.

**219-3.3 HAULING EQUIPMENT.** The mixed recycled concrete aggregate
base course shall be transported from the plant to the job site in
hauling equipment having beds that are smooth, clean, and tight. Truck
bed covers shall be provided and used to protect the mixed recycled
concrete aggregate base course from rain during transport.

**219-3.4 PLACING EQUIPMENT.** Recycled concrete aggregate shall be
placed using a mechanical spreader or machine capable of receiving,
spreading, and shaping the material without segregation into uniform
layer or lift. The placing equipment shall be equipped with a strike off
plate that can be adjusted to the layer thickness. \[**The placing
equipment shall have two end gates or cut off plates, so that the
recycled concrete aggregate may be spread up to a lane width.\]**

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\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

**The Engineer may add additional equipment requirements.**

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\* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \* \*
\* \* \* \* \* \* \* \* \* \* \* \* \* \***

**219-3.5 COMPACTION EQUIPMENT.** Recycled concrete aggregate base
course compaction shall be accomplished using one or a combination of
the following pieces of equipment:

Steel-wheeled roller,

Vibratory roller,

Pneumatic-tire roller,

Hand-operated power tampers (for areas inaccessible to rollers)

**219-3.6 FINISHING EQUIPMENT.** Trimming of the compacted recycled
concrete aggregate to meet surface requirements shall be accomplished
using a self-propelled grader or trimming machine, with a mold board
cutting edge of 12 ft (3.7 m) minimum width automatically controlled by
sensors in conjunction with an independent grade control from a taut
string line. String line will be required on both sides of the sensor
controls for all lanes.

### CONSTRUCTION METHODS

**219-4.1 WEATHER LIMITATIONS.** Construction is allowed only when the
atmospheric temperature is at or above 35 °F (2 °C). When the
temperature falls below 35°F (2 °C), the contractor shall protect all
completed areas against detrimental effects of freezing. Areas damaged
by freezing, rainfall, or other weather conditions shall be corrected.

**219-4.2 PREPARING UNDERLYING COURSE.** The underlying course shall be
checked by the Engineer before placing and spreading operations are
started. Any ruts or soft yielding places caused by improper drainage
conditions, hauling, or any other cause shall be corrected at the
Contractor\'s expense before the base course is placed thereon. Material
shall not be placed on frozen material.

To protect the existing layers and to ensure proper drainage, the
spreading of the recycled concrete aggregate base course shall begin
along the centerline of the pavement on a crowned section or on the
greatest contour elevation of a pavement with a variable uniform cross
slope.

**219-4.3 GRADE CONTROL.** Grade control between the edges of the
recycled concrete aggregate base course shall be accomplished by grade
stakes, steel pins, or forms placed in lanes parallel to the centerline
and at intervals of 50 ft (15 m) or less on the longitudinal grade and
25 ft (7.5 m) or less on the transverse grade.

**219-4.4 MIXING.** The recycled concrete shall be uniformly blended
during crushing operations and mixed with water in a mixing plant
suitable for recycled concrete aggregate. The plant shall blend and mix
the materials to meet the specifications and to secure the proper
moisture content for compaction.

**219-4.5 PLACING.** The recycled concrete aggregate base material shall
be placed on the moistened subgrade or base in layers of uniform
thickness with an approved mechanical spreader.

The maximum depth of a compacted layer shall be 6 inches (150 mm). If
the total depth of the compacted material is more than 6 inches (150
mm), it shall be constructed in two or more layers. In multi-layer
construction, the material shall be placed in approximately equal-depth
layers.

The previously constructed layer shall be cleaned of loose and foreign
material prior to placing the next layer. The surface of the compacted
material shall be kept moist until covered with the next layer.

Adjustments in placing procedures or equipment shall be made to obtain
grades, to minimize segregation grading, to adjust the water content,
and to ensure an acceptable recycled concrete aggregate base course.

**219-4.6. EDGES OF BASE COURSE.** The recycled concrete aggregate shall
be placed so that the completed section will wider, on all sides, than
the next layer that will be placed above it, as shown on the plans.
Approved fill material shall be placed along the free edges of the
recycled concrete aggregate in sufficient quantities to compact to the
thickness of the course being constructed, or to the thickness of each
layer in a .multiple course, allowing in each operation at least a 2-ft
(0.6-m) width of this material to be rolled and compacted simultaneously
with rolling and compacting of each layer of base course. If this base
course material is to be placed adjacent to another pavement section,
then the layers for both of these sections shall be placed and compacted
along the edge at the same time.

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**The Engineer shall show the added width required on the plans,
(generally 1-3' but no more than 5'.**

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**219-4.7 COMPACTION.** Immediately upon completion of the spreading
operations, the recycled concrete aggregate shall be compacted. The
number, type, and weight of rollers shall be sufficient to compact the
material to the required density.

Each layer of the recycled concrete aggregate base course shall be
compacted to the required density using the compaction equipment. The
moisture content of the material during placing operations shall not be
below, nor more than 1-1/2 percentage points above, the optimum moisture
content as determined by ASTM \[ \].

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\* \* \* \* \* \* \* \* \* \* \* \* \* \***

The Engineer shall specify ASTM D 698 for areas designated for aircraft
with gross weights .of 60,000 pounds (27,200 kg) or less and ASTM D 1557
for areas designated for aircraft with gross weights greater than 60,000
pounds (27 200 kg).

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\* \* \* \* \* \* \* \* \* \* \* \* \* \***

The compaction shall continue until each layer has a degree of
compaction that is at least 100 percent of the laboratory maximum
density through the full depth of the layer. The contractor shall make
adjustments in compacting or finishing techniques to obtain true grades,
to minimize segregation and degradation, to reduce or increase water
content and to ensure a satisfactory base course. Any materials found to
be unsatisfactory shall be removed and replaced with satisfactory
material or reworked, so that the requirements of this specification are
met.

**219-4.8 ACCEPTANCE SAMPLING AND TESTING FOR DENSITY.** Recycled
concrete aggregate shall be accepted for gradation and density on a lot
basis. A lot will consist of one day\'s production where it is not
expected to exceed 2,400 square yards (2,000 square meters) per lift. A
lot will consist of one-half day\'s production, where a day\'s
production is expected to consist of between 2,400 and 4,800 square
yards (2,000 and 4,000 square meters) per lift.

Each lot shall be divided into two equal sublots. One gradation and
density test shall be made for each sublot. Sampling locations will be
determined on a random basis in accordance with statistical procedures
contained in ASTM D 3665.

Each lot will be accepted for gradation when it falls within the limits
and tolerances shown in Table 1 when tested in accordance with ASTM C117
and C 131. If the proper gradation is not attained the gradation test
will be repeated. The entire lot shall be rejected and replaced by the
Contractor at the Contractor\'s expense.

Each lot will be accepted for density when the field density is at least
100 percent of the maximum density of laboratory specimens prepared from
samples of the base course material delivered to the job site. The
specimens shall be compacted and tested in accordance with ASTM \[ \].
The in-place field density shall be determined in accordance with ASTM D
1556 or D 2167. If the specified density is not attained, the entire lot
shall be reworked and two additional random tests made. This procedure
shall be followed until the specified density is reached.

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**The Engineer shall specify ASTM D 698 for areas designated for
aircraft with gross weights of 60,000 pounds (27 200 kg) or less and
ASTM D 1557 for areas designated for aircraft with gross weights greater
than 60,000 pounds (27 200 kg).**

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In lieu of ASTM D 1556 or D 2167 method of field density determination,
acceptance testing may be accomplished using a nuclear gage in
accordance with ASTM D 2922. The gage should be field calibrated in
accordance with paragraph 4 of ASTM D 2922. Calibration tests shall be
conducted on the first lot of material placed that meets the density
requirements.

Use of ASTM D 2922 results in a wet unit weight, and when using this
method, ASTM D 3017 shall be used to determine the moisture content of
the material. The calibration curve furnished with the moisture gages
shall be checked as described in paragraph 7 of ASTM D 3017. The
calibration checks of both the density and moisture gages shall be made
at the beginning of a job and at regular intervals.

If a nuclear gage is used for density determination, two random
measurements shall be made for each sublot.

**219-4.9 FINISHING.** The surface of the recycled concrete aggregate
base course shall be finished by equipment designed for this purpose.

In no case will thin layers of material be added to the top of base
course to meet grade. If the elevation of the layer is 1/2 inch (12 mm)
or more below grade, the layer shall be scarified to a depth of at least
3 inches (75 mm), new material added, and the layer shall be
recompacted. If the finished surface is above plan grade, it shall be
cut back to grade and rerolled.

Should the surface become rough, corrugated, uneven in texture, or
traffic marked prior to completion, the unsatisfactory portion shall be
scarified, and recompacted or replaced at Contractor\'s expense.

**219-4.10 SURFACE TOLERANCES.** The finished surface shall not vary
more than 3/8 inch (9 mm) when tested with a 16-ft (4.8-m) straightedge
applied parallel with or at right angles to the centerline. The
Contractor shall correct any deviation in excess of this amount, at the
Contractor\'s expense.

**219-4.11 THICKNESS CONTROL.** The completed thickness of the base
course shall be within 0.5 inch (13 mm) of the design thickness. Four
determinations of thickness shall be made for each lot of material
placed. Each lot shall be divided into four equal sublots. One test
shall be made for each sublot. Sampling locations will be determined on
a random basis in accordance with procedures contained in ASTM D 3665.
Where the thickness is deficient by more than 0.5 inch (13 mm), the
Contractor shall correct such areas at no additional cost by excavating
to the required depth and replacing with new material. Additional test
holes may be required to identify the limits of deficient areas.

**219-4.12 TRAFFIC.** Equipment used in construction may be routed over
completed portions of the base course, provided no damage results and
provided that the equipment is distributed evenly over the full width of
the base course to avoid rutting or uneven

compaction.

**219-4.13 MAINTENANCE.** The base course shall be maintained until the
base course is completed and accepted. Maintenance will include
immediate repairs to any defects and shall be repeated as often as
necessary to keep the completed work intact. Any area of the recycled
concrete aggregate base course that is damaged shall be reworked as
necessary .

### METHOD OF MEASUREMENT

**219-5.1** The quantity of recycled concrete aggregate base course to
be paid will be determined by measurement of the number of square yards
(square meters) of material actually constructed and accepted as
complying with the plans and specifications.

### BASIS OF PAYMENT

**219-6.1** Payment shall be made at the contract unit price per square
yard (square meter) for recycled concrete aggregate base course. This
price shall be full compensation for furnishing all materials, for
preparing and placing these materials, and for all labor, equipment
tools, and incidentals necessary to complete the item. Payment will be
made under:

Item P-219-6.1 recycled Concrete Aggregate Base Course -per square yard
(square meter)

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When multiple lifts are shown on the plans, each lift should be measured
and paid separately.

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### 

### TESTING REQUIREMENTS

ASTM C 29 Unit Weight of Aggregate

ASTM C 117 Materials Finer than 75J.lm (No. 200) Sieve in Mineral
Aggregates by Washing

ASTM C 131 Resistance to Abrasion of Small Size Coarse Aggregate by Use
of the Los Angeles Machine

ASTM C 136 Sieve or Screen Analysis of Fine and Coarse Aggregate ASTM D
75 Sampling Aggregate

ASTM D 693 Crushed Stone, Crushed Slag, and Crushed Gravel for Dry-or
Water- Bound Macadam Base Courses and Bituminous Macadam Base and
Surface Courses of Pavements

ASTM D 698 Moisture-Density Relations of Soils and Soil -Aggregate
Mixtures Using 5.5-lb (2.49-kg) Rammer and 12-in (305-mm) Drop

ASTM D 1556 Density of Soil in Place by the Sand -Cone Method

ASTM D 1557 Moisture-Density Relations of Soils and Soil-Aggregate
Mixtures Using 10-lb (4.5-kg) Rammer and 18-in (457-mm) Drop

ASTM D 2167 Density of Soil in Place by the Rubber-Balloon Method ASTM D
2419 Sand Equivalent Value of Soils and Fine Aggregate

ASTM D 2922 Density of Soil and Soil-Aggregate in Place by Nuclear
Methods

ASTM D 3017 Moisture Content of Soil and Soil-Aggregate in Place by
Nuclear Methods

ASTM D 3665 Random Sampling of Paving Materials

ASTM D 4318 Liquid Limit, Plastic Limit, and Plasticity Index of Soils

**END OF P-219**

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