NATURAL RESOURCES CONSERVATION SERVICE

**Idaho**

**CONSTRUCTION SPECIFICATIONS**

**FOR**

**LINED WATERWAY OR OUTLET**

**(CONCRETE LINING)**

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

(Owner/Operator)

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

(Project Title)

GENERAL

Installation shall be in accordance with an approved design and plan.
Details of construction shown on the drawings but not included herein
are considered as a part of this specification. Construction activities
shall be in accordance with applicable OSHA regulations.

FOUNDATION PREPARATION

The foundation area for the lining shall be cleared of all trees, weeds,
roots, sod, loose rock or other materials not suitable for the subgrade.
Cleared material shall be disposed of as shown on the drawings.

The waterway shall be shaped to the cross section shown on the drawings.
Fill materials shall be free of brush, roots, sod, large rocks or other
material not suited for making compacted fills. The moisture content and
methods of placing the material shall be such that a firm, stable fill
will result. The fill materials shall be placed in horizontal lifts of
such thickness that compaction density of fills is similar to adjacent
undisturbed earth materials. However, prior to compaction the thickness
of individual layers being compacted by mechanical equipment shall not
exceed 8 inches.

CONCRETE

Concrete shall be proportioned so that it is plastic enough for thorough
consolidation and stiff enough to stay in place on the side slope of the
ditch.

[Concrete compressive strength]{.underline} shall be at least 3000 psi
at 28 days. The mix design shall be in accordance with ASTM C 94 and
this specification. The concrete shall be proportioned to include not
less than 5 sacks cement per cubic yard of concrete when a water
reducing admixture is used, except fly ash may be used as substitution
for not greater than 20 percent of the Portland cement.

[Certification of concrete]{.underline}. Ready-mix concrete suppliers
can precertify their concrete mix. When a precertified mix is used the
mix number will be shown on the concrete delivery ticket. Non-certified
ready-mix suppliers shall furnish mix design and concrete cylinder test
break data for Technician approval prior to placement.

At the discretion of the responsible Technician, any concrete being used
on a lining project shall be subject to sampling and testing in
accordance with ASTM C 31 and C 39. Should the test results show that
the average 28 day compressive strength of three cylinder specimens is
less than 3000 psi, the job shall not be accepted as meeting
specifications.

[Cement]{.underline} shall be low alkali Type II or IIA Portland cement
unless otherwise specified.

[Fly ash]{.underline} shall conform to requirements of ASTM C 618 as
applicable.

[Water reducing admixtures]{.underline} shall be Type "A" meeting the
requirements of ASTM C 494.

[Coarse aggregate]{.underline} shall be maximum size of 1-1/2 inches per
designations in ASTM C 33.

##### [Air entrainment]{.underline} conforming to the requirements of ASTM C 260, shall be used. The air content shall be 5 to 7 percent.

[Concrete slump]{.underline} conducted in accordance with ASTM C 143
shall not exceed 3 inches.

CONCRETE PLACEMENT

Concrete for linings shall be placed on moist, compacted surfaces free
from debris, loose soil, mud, frozen ground or standing water. The
foundation shall be moistened to a depth of at least 1/2-inch.

FINISHING AND CURING

All concrete linings shall have a smooth and uniform finish and shall be
free of honeycombed or sandstreaked areas.

A concrete curing compound shall be applied to the concrete surface
immediately after placing and/or finishing. The sealing compound shall
meet or exceed the requirements of ASTM C 309 and shall be Type 1-D,
clear with fugitive dye or Type 2, White pigment. The sealing compound
shall be applied at a minimum rate of 1 gallon per 200 square feet of
surface area. The sealing compound shall be applied in a manner that
will insure a continuous, uniform coverage of membrane film over the
entire surface of the exposed concrete in the ditch.

In lieu of applying a curing compound, water curing by ponding water in
the lined ditch for a minimum of 5 days is acceptable.

Excessive shrinkage cracks that develop prior to final inspection shall
make the concrete lining unacceptable per these specifications, such
concrete shall be removed and replaced.

When it appears that temperatures of less than 32 degrees Fahrenheit may
occur within three days after placing of the lining, one of the
following actions shall be taken:

1.  Cover the entire length of the lining with 6 mil black plastic,
    making sure to restrict any air movement under the covering by
    blocking the ends.

2.  Cover the entire length of lining with a minimum of 6 inches of
    straw.

3.  Pond water in the waterway to its maximum capacity.

Concrete damaged by freezing shall be considered as not meeting these
specifications and must be removed and replaced.

The use of accelerators or antifreeze compounds will not be allowed.

CONTRACTION & CONSTRUCTION JOINTS

Contraction joints, at least 1/4 inch wide, shall be cut transversely in
the freshly placed concrete to a depth of 1/3 the thickness of the
lining at an average spacing of not greater than 10 feet. The maximum
contraction joint spacing shall not exceed 11 feet. Construction joints
shall be butt type, formed square with the lining surface and at right
angles to the centerline of the ditch. Contraction and construction
joints shall be tooled so that the edges have a smooth finish. It is
recommended that all joints be filled with a sealer conforming to the
requirements of ASTM D 1850.

CLEAN-UP

After construction the site shall be cleared of all unused materials.

###### ADDITIONAL SPECIFICATIONS