13 - Annual Concrete Demolition and Construction Bids

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strength of not less than 3,000 pounds per square inch at 28 days. Reinforcing steel shall be #3 bars on 18" centers both ways located two inches (2") below the top surface of the sidewalk. As soon as the concrete has obtained its initial set, a white pigmented approved curing compound shall be applied. B. Construction Procedure: In general, the grade of the sidewalks shall be established with respect to the curb. Forms shall be set for all sidewalk and shall be true to line and grade. Forms shall be set to provide a minimum cross slope of '/ inch per foot across the sidewalk toward the street. All forms shall remain in place at least twenty-four (24) hours. The plane of all joints shall make a right angle with the surface of the pavement. No joints shall have an error in alignment of more than one-half (1 /2") inch at any point. The edges of the slab at all joints, except where joints are sawed, shall be rounded with an edger having a radius of one- quarter (1/4") inch, except as otherwise shown on the plans. The edging shall also be done symmetrically on each section with plane of the joint. Longitudinal expansion joints, joints used to separate new from old concrete, and joints around all fire hydrants shall be made of conventional one-half (1/2") inch asphalt expansion joint material extending completely through the concrete unless otherwise specified on the plans. Contraction joints shall be made in the sidewalk at regular intervals, such intervals generally being equal to the width of the sidewalk. The contractor shall grade or fill, as necessary, along the sidewalk to match the existing ground. Care Ai 11 be used to insure that adjacent property outside the right-of-way line is protected. 6. Curing: All concrete shall be cured by protecting it against loss of moisture for a period of not less than seventy-two (72) hours. Immediately after the surface water sheen has disappeared, impervious membrane curing compound shall be applied uniformly to the surface of the pavement. The membrane curing compound shall be sprayed in one application at a rate of not less than one gallon to one hundred eighty (180) square feet of pavement area. The concrete surface to which membrane curing compound is applied shall be protected from abrasion or damage which results in perforation of the membrane film during the first seventy-two (72) hours after application. After removal of forms, the sides shall be coated with membrane curing compound prior to the banking of earth against them. The curing method as herein specified does not preclude the use of any of the other commonly used methods of curing, and the Engineer may approve them if so requested by the contractor. Payment for curing is considered subsidiary to other bid items in this contract. 7. Approved bidder is responsible for the demolition, disposal and cleanup of existing curb/gutter, driveway approaches or sidewalk. 8. Approved bidder is responsible for the construction of new curb/gutter, driveway approaches or sidewalk. All construction must comply with American Disabilities Act and standard TXDOT specifications, except as amended by the project specifications or drawings to be provided by the City.