CONSTRUCTION SPECIFICATION

NE-51. CORRUGATED METAL PIPE CONDUITS

1\. [SCOPE]{.underline}

The work shall consist of furnishing and placing corrugated metal pipe
and the necessary fittings as shown on the plans.

2\. MATERIALS

Pipe and fittings shall conform to the appropriate ASTM requirements of
material shown on the drawings.

3\. HANDLING THE PIPE

The Contractor shall place the pipe without damaging the pipe or
coatings.

Whenever the pipe is damaged, it shall be repaired as provided in
Section 4.

4\. REPAIR OF DAMAGED COATINGS

Breaks, scuffs, or other damage to the various coatings shall be
repaired by thoroughly wire brushing the damaged area and cleaning with
solvent and as follows:

A. Zinc Coating and Aluminum Coating - apply two coats of one of the
following paints:

> \(1\) Zinc Dust - Zinc Oxide Primer conforming to Federal
> Specification TT-P-641, Type III.
>
> \(2\) Zinc Dust Chlorinated Rubber conforming to Federal Specification
> TT-P-1046a.
>
> \(3\) Zinc Dust Paint conforming to Military Specification
> MIL-P-21035.

B. Bituminous Coating - apply two coats of hot asphaltic paint or a
coating of cold-applied asphalt mastic. The repair coating after
hardening shall bond securely and permanently to the pipe.

C. Polymer Precoated - apply two coats of polymer coating similar and
compatible to the original polymer coating as per manufacturer\'s
recommendations, or apply two coats of cold-applied asphalt mastic.

5\. LAYING AND BEDDING THE PIPE

The pipe shall be laid to the line and grade shown on the drawings and
shall be firmly and uniformly bedded throughout its entire length.

Bedding the pipe shall be one of the following procedures:

Pipe should be laid on a moist, compacted foundation (not wet nor hard
and dry). Just before the pipe is laid, spread a 2- to 3-inch layer of
moist, loose soil for the pipe to be placed on. The pipe should make
uniform contact with the soil along its entire length.

In lieu of spreading a 2- to 3-inch layer of moist, loose soil, the
foundation should be disked along the entire pipe length to a 2- to
3-inch depth and the foundation \"crumbed\" for the pipe to be placed
on.

The pipe shall be laid with the outside laps of circumferential joints
pointing upstream and with longitudinal laps on the sides at
approximately the vertical mid-height of the pipe. Field welding of
corrugated galvanized steel pipe will not be permitted. The pipe
sections shall be joined with coupling bands.

6\. BACKFILLING

Special care shall be taken during backfill operations not to disturb
the grade and alignment.

The pipe shall be tied down or loaded sufficiently during backfilling
around the sides to prevent its being lifted from the bedding.

Backfill material shall have sufficient moisture so that optimum
compaction can be obtained. Backfill around the pipe shall be placed in
layers not more than 4 inches thick before compaction.

Each layer of backfill shall be compacted with power tampers, hand
tampers, or plate vibrators to the same density requirements as
specified for the adjacent embankment. Backfill over and around the pipe
shall be brought up uniformly on all sides and shall extend a minimum of
2 feet over the pipe before earth embankment with earth moving equipment
over the pipe is started.