Sidewalks shall not be less than four inches in thickness and expansion paper shall be placed in the joints. Sidewalks at driveway crossings shall be not less than six inches in thickness. All concrete used in sidewalk construction shall, 28 days after placement, be capable of resisting a pressure of 3,500 pounds per square inch without failure. The City Manager may establish additional detailed specifications in addition hereto and not inconsistent herewith.
(1981 Code § 4.64)