630PLAIN CEMENT CONCRETE CURB

630.1DESCRIPTION —This work is construction of plain cement concrete curb , plain cement concrete

depressed curb for curb ramps, and reinforced cement concrete depressed curb for driveways .

630.2MATERIAL—

• Class A Cement Concrete. Section 704

• Class A Cement Concrete (Slip-Forming). Section 704, except with a maximum slump of 1 1/2 inches

• Premolded Expansion Joint Filler. Section 705.1

• Covers for Curing and Protection. Section 711.1

• Curing Compound. Section 711.2(a)

• Mortar. Section 1001.2(d)

• Caulking Compound. Section 705.7

• Reinforcement Bars. Section 709.1(a)

630.3CONSTRUCTION—As shown on the Standard Drawings, as specified in Section 501.3, and as follows:

lines if indicated. Then, compact the material, upon which the curb is to be constructed, to a firm even surface.

curves and short tangent sections. Use forms that will not discolor the concrete.

as specified in Section 501.3(b). Place the concrete in the forms in layers not exceeding 5 inches in depth if spading, or layers not exceeding 15 inches in depth if using a vibrator to eliminate voids. Provide drainage openings through the curb, at the elevation and of the size required, where indicated or directed. Smoothly and evenly finish the top surface of the curb using a wood float. Round the edges of the face and back of the curb top while the concrete is still plastic. Place depressed curbs for drives or curb ramps, where indicated or directed. Place bars as indicated for depressed curb at drives as specified in Section 1002.3. Cure concrete as specified in Section 501.3(l).

Uniformly feed the concrete to the machine so it maintains the shape of the section without slumping after extrusion. The Representative will not allow voids or honeycomb on the surface of the finished curb. Immediately after extrusion, perform any additional surface finishing.

specified in Section 501.3(i)2. Place 3/4-inch premolded expansion joint material conforming to the cross - sectional area of the curb where indicated and at the end of the workday. Prepare and caulk joints according to caulking manufacturer’s recommendations.

Correct irregular surfaces by rubbing with a carborundum stone. Do not brush finish or plaster. Fill minor

defects with mortar.

front and back of the curb, using acceptable embankment material, as specified in Section 206.3(b)4. Complete embankments in back of raised curbs, as indicated, and as specified in Section 206.3, except carefully compact the embankment by means of mechanical tampers, or rollers, if allowed, not exceeding 8 tons. Replace existing pavement and sidewalk damaged or removed during construction. Dispose of unsuitable and surplus material.

where indicated or directed. Drill holes and insert dowel bars with non-shrink mortar, as required.

reinforcement bars to extend the entire length of the depressed curb and sloped sides.

across the curb width as indicated or directed. Construct the depressed curb flush with the adjacent roadway surface elevation. Install depressed curb for all curb ramps and at median or traffic refuge island access openings where the opening meets adjacent roadway pavement. The contractor may place cement concrete for depressed curb monolithically with curb ramps, side flares or both. Do not place cement concrete curb monolithically with other cement concrete sidewalk.

630.4MEASUREMENT AND PAYMENT —Depressed curb will be measured and paid for as full depth

curb of the type indicated. If depressed curb is placed monolithically with curb ramps, side -flairs or both, the depressed curb will be measured and paid separately from the curb ramps and side flairs.