One-course sidewalks shall be constructed as follows: A subgrade shall be prepared by cutting down or filling up the surface of the ground to an elevation which, after being thoroughly compacted, shall be five inches (5") below the sidewalk grade. Wherever filling is necessary, it shall be done with earth, or other material equally as good for filling purposes, free from animal or vegetable matter, thoroughly compacted, and placed in layers not more than twelve inches (12") in thickness.
Upon the subgrade shall be placed a layer of Portland cement concrete five inches (5") in thickness. The concrete shall consist of one part Portland cement, two (2) parts torpedo sand and three (3) parts crushed stone or gravel measuring not less than one-fourth inch (1/4") nor more than one and one-half inches (11/2") in any dimension, all of which shall be free from dust, loam and dirt or other foreign substance. The materials shall be thoroughly mixed with water in a batch mixer or mixed by hand, in which event the cement and sand shall be thoroughly mixed dry, into which shall be incorporated the three (3) parts of stone as specified herein, after which the mixture shall be moistened with water and the whole mass thoroughly mixed and placed on the foundation and rammed until solid. The concrete shall be struck off and finished in such a manner as to ensure a smooth and even surface. (Ord. 27, 1928)