- Form the foundation by excavating or filling to the required elevation of the concrete bottom, or subbase bottom if specified. Tamp or compact the foundation to ensure stability. In cuts, make the foundation wide enough to allow placing forms and performing concrete placement and finishing. On embankments, construct the foundation at least 2 feet wider than the proposed sidewalk and extend it at least one foot beyond each end of the sidewalk.
- Unless specified otherwise, fill holes, ruts, and other depressions in the foundation with materials similar to those in the existing foundation. The contractor may use granular sub base or aggregate base.
- If the plans show, place granular sub base or aggregate base to the thickness and section the plans show.
Furnish and use wood or metal forms straight and of sufficient strength to resist springing, tipping, or other displacement during depositing and consolidating the concrete. If using wood forms, provide surfaced planks, at least 2-inch nominal thickness stock except for sharply curved sections. If using metal forms, ensure they are the engineer-approved section with a flat surface on top. Use forms as deep as the depth of the sidewalk. Securely stake, brace, and hold the forms firmly to the required line. Make the forms tight to prevent mortar leakage. Clean and oil before placing concrete against them.
Placing and Finishing Concrete - The engineer will check and approve the foundation, forms, and reinforcement if required, before placing the concrete. Place the concrete on a moist foundation, deposit it to the required depth, and consolidate sufficiently to bring the mortar to the surface, then strike-off and finish to a true and even surface. Before the mortar sets, brush or lightly broom the surface. Before performing the final surface finish, check the sidewalk surface with a 10-foot straightedge, and correct areas that vary 1/4 inch from the testing edge by adding or removing concrete while the concrete is still plastic. If the engineer allows, the contractor may construct concrete sidewalks with suitable, engineer-approved, slip-form equipment. Construct curb ramps at the locations and conforming to the details and dimensions the plans show. Embed detectable warning fields in plastic concrete conforming to manufacturer-recommended procedures.
