2415.01 DESCRIPTION.
The provisions of this section shall apply to all cast-in-place concrete culverts. The requirements of Sections 2401, 2402, 2403, 2404, and 2414 shall also apply.

Precast box culverts may be accepted when shown in the contract documents. These culvert sections shall meet requirements of ASTM C 1433. The contract documents will designate the span, rise, and either the design earth cover, as defined in ASTM C 1433 or the design loading, as defined in ASTM C 1433. Section 2407 shall apply to the aggregates used in the concrete. Appropriate requirements of Section 2407 shall also apply to inspection of the process of manufacture. Concrete strength will be based on cylinder tests.

2415.02 FOOTINGS.
The footings shall be constructed to the elevations shown in the contract documents unless otherwise directed by the Engineer. Footing depths may be increased when necessary to prevent undermining or scour or to secure adequate bearing. In general, footing depth shall be decreased only when solid rock is encountered at elevations above those shown. Suitable wood or metal forms shall be used to enclose all footing concrete.

2415.03 CLASS OF CONCRETE.
All concrete shall be Class C structural concrete meeting requirements of Section 2403, unless otherwise specified.

2415.04 PLACING CONCRETE.

A. Footings.
Care shall be taken to prevent dirt, mud, or other foreign material from becoming mixed with concrete which is being placed in the footing. The footings, pavements, and curtain walls between construction joints shall be constructed monolithic if practicable. A key notch of the form shown in the contract documents shall be provided between the walls and footings to insure proper anchorage. All dirt, dust, shavings, or other foreign material shall be removed from the key notch and wall forms before placing concrete.

B. Barrels of Culverts.
The sidewalls and top slab may be constructed as a monolith between construction joints, or the concrete in sidewalls may be placed and allowed to harden before the top slab is placed, at the discretion of the Contractor. If the sidewalls and top slab are constructed as a monolith, any necessary construction joints shall be vertical and at right angles to the axis of the culvert. If the sidewalls are placed and allowed to harden before the top slab is placed, appropriate keys shall be left in the sidewalls for anchoring the cover slab. Forming and reinforcement for the entire barrel section between construction joints shall be in place before any concrete is placed in the sidewalls or headwalls.

C. Headwalls.
In general, the headwalls shall be constructed monolithic. However, when construction joints are unavoidable, they shall be placed in a horizontal or vertical position and located so that no joint is visible above the roadbed. Sharp edges and corners shall be avoided by means of triangular fillet strips placed in the forms.

D. Placing Concrete in Arch Culverts.
Concrete in arch culverts shall be placed as provided in Section 2403.

2415.05 SURFACE FINISH.
All exposed parts of the wingwalls, headwalls, and railings shall be surface finished in accordance with Article 2403.21.

2415.06 BACKFILLING.
Backfilling shall be performed in accordance with Article 2402.09.

2415.07 PROTECTION RAILINGS.
Protection railings shown in the contract documents shall be furnished and installed by the Contractor. Protection railings other than aluminum or galvanized railings shall be painted as provided in Section 2508.

2415.08 METHOD OF MEASUREMENT AND BASIS OF PAYMENT.
All concrete box, arch, or circular culverts will be paid for at the contract unit price for excavation for structures, structural concrete, steel reinforcement, and other items included in the contract documents. Protection railings, when specified in the contract documents, will be paid for at the contract unit price for the railing material. These payments shall be full compensation for furnishing all materials, equipment, and labor and for performance of all work necessary to complete the structures in conformance with the contract documents or as ordered by the Engineer.