(a) The sidewalk shall consist of one course concrete of not less than four inches in thickness, mixed in the proportion of one part of Portland cement to two parts of fine aggregate and three parts of coarse aggregate. All materials shall be accurately measured in manner to be approved by the Inspector. When the location of driveways is known, the thickness of the walk shall be increased to not less than six inches, and mixed in the same proportions as for four inch sidewalks.
(b) The ingredients of the concrete shall be thoroughly mixed until each particle of fine aggregate is coated with cement and each particle of coarse aggregate is coated with mortar. The consistency of the mixed concrete shall be such that separation of the ingredients take place and some tamping is necessary to bring the mortar to the surface.
(c) The freshly mixed concrete shall be placed immediately on the prepared subbase and tamped sufficiently to produce a uniform slab. It shall then be struck off with a straight edge resting upon the side forms and advanced with a crosswise sawing motion. It shall then be floated with a wooden float until the surface is true and the concrete is thoroughly compacted. The placing of concrete shall not be suspended for forty-five minutes or longer except at the end of the slab. No concrete shall be placed when the temperature is liable to be within twenty-four hours, below thirty-five degrees Fahrenheit, except with the written permission of the Inspector.
(d) The walk shall be divided into separate rectangular slabs, by means of strips of paper or division plates. No plain concrete slab shall have an area of more than thirty-six square feet. The division plates shall be removed only after the concrete has set sufficiently to avoid breaking the edges or corners of the slabs. The surface edges of each slab shall be rounded to a radius of about one quarter inch.
(e) As soon as the concrete has set sufficiently, it shall be sprinkled with water and kept moist until it has set sufficiently to be opened to traffic. The contractor shall protect the concrete from damage by rain, pedestrians and animals by means of suitable barricades and coverings, and by red lights at night.
(Ord. 1973-6. Passed 2-22-73.)