UNITED STATES DEPARTMENT OF AGRICULTURE

NATURAL RESOURCES CONSERVATION SERVICE

OREGON

[CONSTRUCTION SPECIFICATION]{.underline}

[CS-43 CONCRETE CANAL LINING]{.underline}

43.1 [SCOPE]{.underline}

> This construction specification is applicable for the construction and
> installation of with non-reinforced slip-formed concrete lined field
> ditches, canals and laterals. The field ditches, canals and laterals
> shall be constructed at the location and to the dimensions as shown in
> the plan.

43.2 [SITE PREPARATION]{.underline}

> The foundation area shall be cleared of vegetation, inorganic material
> and rocks with a dimension greater than 2 inches. The fill material
> shall be placed in horizontal layers with a maximum lift of 4 inches
> before compaction. The moisture content of the fill material shall be
> adequate so that a firm dense foundation can be achieved. Fill
> sections with a height of 2 feet or greater will be constructed using
> the compaction requirements of Construction Specification CS-14 or
> CS-15 for Earth Fill. Other compaction methods approved by the NRCS
> technician may be used, if the fill sections are allowed seasonal
> consolidation for at least a 6-month period.

43.3 [MATERIALS]{.underline}

> The materials required for this practice are detailed in Material
> Specifications, MS-201, Aggregate, MS-202, Portland Cement and MS-203,
> Concrete. The concrete mix shall be approved by the NRCS technician
> prior to placement.

43.4 [CONSTRUCTION]{.underline}

> a\. [Foundation]{.underline}:
>
> The foundation surface for the concrete lining shall be moist when the
> concrete is placed. The concrete shall not be placed on mud,
> excessively dry soil, non-compacted fill, ice or frozen soil.
>
> b\. [Placement]{.underline}:
>
> Slip-forms shall be operated to achieve a uniform thickness of the
> concrete lining. The minimum thickness of the concrete shall be 2
> inches.
>
> c\. [Control and Construction Joints:]{.underline}
>
> Control joints shall be 1/4" wide perpendicular of the concrete
> lining, at a depth equal to one-third of the lining thickness with a
> uniform spacing not to exceed 10 feet. Construction joints shall be
> the butt type, formed square with the lining surface and at right
> angles to the ditch or canal. Control and construction joints shall
> have smooth finishes.
>
> d\. [Curing]{.underline}:
>
> The concrete shall be cured for not less than 5 days using one of the
> following methods:
>
> 1\. Impounding water over the exposed surface.
>
> 2\. Covering with burlap or a similar material that is kept
> continuously moist.

3\. Spraying with a curing compound conforming to ASTM C-309, Liquid
Membrane Forming Compounds for Curing Concrete. The curing compound
shall be applied at a uniform rate of not less than one gallon per 150
square feet of surface area. It shall form a uniform continuous,
adherent film that will not check, crack or peel. All surfaces shall be
kept moist until the compound is applied.

> e\. [Concreting in Cold Weather]{.underline}:
>
> Provisions for placing concrete in cold weather shall apply when the
> average daily temperature is less than 40^o^F or when the maximum
> daily temperature is less than 50^o^F for 12 hours or less in a
> 24-hour period.
>
> 1\. Concrete linings shall not be placed when the ground temperature
> is less than 40^o^F.
>
> 2\. Prior to the placement of concrete all ice, snow and frost shall
> be completely removed from all surfaces to be in contact with the
> concrete.
>
> 3\. The temperature of the concrete at the time of placement shall not
> be less than 50^o^F nor more than 90^o^F. Heated water shall not
> exceed 140^o^F when cement is added to the mix.
>
> 4\. The use of antifreeze or accelerator compounds is not allowed.
>
> 5\. When the daily minimum ambient air temperature for the nearest
> weather station is predicted to be less than 40^o^F within a 3-day
> weather forecast, the concrete shall be insulated for 48 hours within
> 1 hour after placement using one of the following methods:
>
> \(a\) Eight inches of straw covered with a polyethylene film.
>
> \(b\) Two inches of sawdust or shavings covered with a polyethylene
> film.
>
> \(c\) One-inch thick mineral fiber blanket.
>
> 6\. In lieu of providing frost protection, the owner may proceed with
> the understanding that if the fresh concrete is unprotected and
> subjected to freezing temperatures within 48 hours after placement and
> the concrete lining will not be accepted as meeting this
> specification.

43.5 [DELIVERY TICKETS]{.underline}

> The delivery tickets shall identify the mix delivered to the site and
> all ingredients by weight except water and admixtures which may be
> measured by volume. If additional water is to be added at the job
> site, the volume of water shall also be identified on the delivery
> ticket. The delivery tickets shall be furnished to the NRCS
> technician.

43.6 [ACCEPTANCE]{.underline}

> The final acceptance of the work will be by inspection and to
> conformance to the requirements of this construction specification.

7.  [ITEMS OF WORK AND CONSTRUCTION DETAILS FOR THIS
    PROJECT]{.underline}