147. Expansion Joints.—After the laying of both courses of concrete is completed expansion joints at right angles to the sidewalk, and not more than four (4) feet apart shall be constructed in the sidewalk in the following manner: the joint will be located by a line on the surface of the sidewalk and a straight-edged cutting tool one-fourth (¼) inch thick will be used to cut entirely through both courses of concrete, accurately along the line marked out, entirely across the sidewalk, after which a T-shaped trowel or tool shall be used to smooth and compact the cut surfaces for a depth of one inch, and to round off the corners of the sidewalk blocks to a radius of one-fourth (¼) inch.[[86]]

Where the ends of the sidewalk abut against the curbing a clear expansion joint one and one-fourth (1¼) inches wide shall be left between the sidewalk and the curb.

148. After the concrete laying is completed it shall be protected from use or injury until the concrete is set hard enough to withstand travel, and it shall be kept continuously damp for at least five days after the concrete is laid.

149. Weather.—Concrete in sidewalks shall not be laid in freezing weather nor shall frozen materials be used in the work. Completed work must be securely protected from frost for at least seven days after the concrete is laid. Any concrete sidewalk that shall become frozen within that period of time shall be wholly taken up and replaced with new work, at the expense of the contractor.

150. Regrading.—Directly after the concrete is completed, the forms removed, and the work inspected by the engineer, the space between the outer edge of the sidewalk and the street curb shall be excavated or filled up and dressed to a plane one inch below the top of the sidewalk and the top of the street curb; and the space on the inner side of the sidewalk shall be graded to a plane one inch below and parallel to the surface of the sidewalk for a distance of two feet back from the edge of the sidewalk and completed with a slope of one and one-half to one to the natural surface of the ground. Where this regrading requires filling up the filling material, for a depth of four inches from the surface, shall be good, rich surface soil.

151. Should any defects due to faulty material or workmanship develop in the sidewalk within one year after the completion of the same the contractor shall repair or reconstruct all such defective places at his expense, doing the work in accordance with these specifications.

152. Measurement and Payment.—Concrete sidewalk will be measured and paid for by the square foot of completed sidewalk surface, and the unit price per square foot shall cover the entire cost of the work, including grading, drainage work, all material and labor, forms, and the regrading or dressing up after the completion of the concrete work; except that the drain pipe used will be paid for per linear foot at the price named in the contract which price shall cover the cost of furnishing and putting the pipe in place complete.

PART II
INSTRUCTIONS TO INSPECTORS ON STREET PAVING WORK

INTRODUCTORY NOTE

Any general code of instructions for inspectors on street paving work must necessarily be little more than tentative or suggestive, as applied to any one city.