2417.01 DESCRIPTION.
Corrugated culverts shall be furnished and installed in conformance with the contract documents and the following provisions. The definitions of roadway and entrance culverts shall be as defined in Article 2416.01.

2417.02 MATERIALS.
Corrugated culverts shall meet requirements of Section 4141 or 4146 when polyethylene culvert pipe is designated.

Culverts shall be round pipe, unless otherwise specified. When required, round pipe shall be elongated. When specified, culverts shall be of the pipe arch type.

When required, corrugated iron and steel culverts shall be coated according to Article 4141.02.

A paved invert may be required according to the contract documents.

2417.03 MAXIMUM AND MINIMUM SIZES.
For roadway culverts, the minimum permissible diameter shall be 18 inches (450 mm).

For entrance culverts, the minimum permissible diameter shall be 15 inches (375 mm).

The maximum diameter for corrugated culverts shall be 84 inches (2100 mm) for pipe with a 1/2 inch (13 mm) corrugation depth and 120 inches (3000 mm) for pipe with a 1 inch (25 mm) corrugation depth.

When culverts of sizes outside these limitations are specified, they will be covered by the contract documents.

2417.04 MINIMUM DEPTH OF FILL.
The minimum depth of fill over entrance culverts shall be 1 foot (0.3 m). The minimum depth of fill over roadway culverts shall be 2 feet (0.6 m) and shall be increased, if necessary to accommodate construction traffic, to the nominal diameter of the pipe or 3 feet (1 m), whichever is greater.

2417.05 INSTALLATION.
Installation of corrugated metal pipe or polyethylene pipe for roadway culverts shall be with a Class A bedding.

A. Class A Bedding.
Class A bedding shall consist of a uniform uncompacted cushion of sand as detailed in the contract documents and meeting the gradation requirements of Gradation No. 1 or 32 of the Aggregate Gradation Table referenced in Section 4109.

B. Deflection Testing for Polyethylene Pipes.
No sooner than 30 calendar days following compaction of pipe installation and backfilling, or before paving, the Contractor shall perform deflection testing on at least 10% of the pipe locations along their entire length at locations as determined by the Engineer. The internal diameter of a pipe shall not be reduced by more than 6.5% of its nominal inside diameter. If any pipe fails post installation testing, the Engineer may require the Contractor to perform post installation testing on any additional pipes or all of the remaining pipes. Pipes failing post installation testing shall be considered unacceptable. New pipe or pipe that is not damaged shall be reinstalled. The reinstalled pipe shall be tested for deflection.

1. Pipe Diameter of 30 Inches (750 mm) or Less.
Deflection testing shall be performed using a properly sized nine-point mandrel test.

2. Pipe Diameter Greater than 30 Inches (750 mm).
A measurement by the Contractor shall be made to insure the internal diameter of the entire length of the pipe is not reduced by more than 6.5% of its nominal inside diameter.

2417.06 METHOD OF MEASUREMENT.
The quantity of corrugated pipe culvert, in feet (meters), will be the measured length of culvert installed, excluding aprons, to the nearest foot (0.1 m). The quantity of pipe will be determined along the axis. Pipe laterals terminating at a tee will be measured from the point of inlet to a point 6 inches (150 mm) from the outside of the main, less the length of the apron, if any.

The quantity of aprons and other fittings will be the quantity shown in the contract documents.

The quantity of appurtenances (elbows, tees, and other fittings) will be shown on the contract documents but will not be measured for payment.

Excavation for roadway culverts will be measured in accordance with Article 2402.12, B. Excavation for entrance culverts will not be measured for payment.

When granular backfill is required and furnished, measurement will be in accordance with Article 2402.12, D.

When foundation treatment material has been placed at the written direction of the Engineer, measurement will be in accordance with Article 2402.12, E.

2417.07 BASIS OF PAYMENT.
The Contractor will be paid the contract unit price for corrugated pipe culvert of the type and size specified per linear foot (meter).  Appurtenances shall be included in the contract unit price per linear foot (meter) for the corrugated pipe culvert.

The Contractor will be paid the contract unit price for aprons of the size specified per unit.

For the quantity of excavation for roadway culverts and the quantity of extra excavation for embankments, the Contractor will be paid the contract unit price per cubic yard (cubic meter).

For entrance culverts, excavation shall be considered as incidental to the contract unit price for corrugated pipe culverts.

When Granular Backfill is required and furnished, it will be paid for in accordance with Article 2402.13, F.

The cost of deflection testing required according to the contract documents will be considered incidental to the contract unit price for polyethylene pipe.

Foundation treatment material furnished and placed will be paid for in accordance with Article 2402.13, E.