Section 02510 Concrete Walkways - Laserfiche WebLink

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02510 - 4/5 2. Form contraction joints by any of the following methods: a. Place one half inch thick steel separators after concrete has taken its initial set, but before final finishing. b. Cut a groove in the fresh concrete to a depth of at one quarter the section thickness by use of a jointer having a radius of one half inch and thickness not exceeding one half inch. c. Saw the hardened concrete before shrinkage cracking occurs. Depth of cut not less than one quarter the section thickness and width of key not to exceed three sixteenths inch. B. Expansion Joints: 1. Construct at the following locations: a. Locations as indicated. b. All points of curvature and points of tangency of curves having a radius of 100 inches or less and at intervals not exceeding 60 inches in tangent section. c. Locations where curb abuts other structures and slabs. 2. Stake, support, and secure preformed joint filler in position to prevent displacement during and finishing operations. 3. Round edges of joints with an edging tool of one quarter inch radius. C. Construction Joints: 1. Locate to coincide with contraction, expansion or key joints. 2. When concrete placement is interrupted between joint locations for a sufficient time for the concrete to take its initial set, remove concrete to the nearest joint location before resuming placement. 3.08 STRAIGHTEDGING AND SURFACE CORRECTIONS A. After floating has been completed and the excess water removed, but while the concrete is still in a plastic state, the surface of the concrete shall be tested for trueness with an accurate 10 foot straightedge. The straightedge shall be furnished by the CONTRACTOR. The straightedge shall be held in successive positions parallel to the road center line, in contact with the surface, and the whole area tested from one side of the slab to the other as necessary. Any depressions shall be immediately filled with freshly mixed concrete and struck-off, consolidated and refinished. High areas shall be cut down and refinished. Straightedge testing and surface correction shall continue until the entire surface appears to conform to the required grade and cross section. 3.09 FINAL FINISH: As soon as the water sheen has disappeared from the surface of the pavement and just before the concrete becomes nonplastic, a light broom finish shall be given to the surface. 3.10 EDGING A. After the final finish has been applied, but before the concrete has become nonplastic, the edges of the pavement along each side of the strip being placed, on each side of construction joints and along any structure extending into the