A. Longitudinal construction joints shall be tied with number four deformed tie bars, thirty inches long at thirty-inch intervals. Sawed contraction joints at twenty-foot intervals.
B. The concrete shall meet the following requirements:
1. Have a compressive strength of three thousand five hundred pounds per square inch in fourteen days or a modulus of rupture equal to six hundred fifty pounds per square inch in fourteen days;
2. Have a minimum of six bags of cement per cubic yard of concrete;
3. Have a workable slump approved by the city engineer, but in no instances greater than three inches;
4. Mix shall be submitted to the city engineer for approval prior to beginning construction operations; test data must accompany the mix proportions to verify the strength of the proposed mix;
5. Be field tested for strength by the certifying engineer or independent testing laboratory during construction by taking beam or cylinder specimens at the minimum rate of two per five hundred feet per lane or two per day, whichever is greater;
6. Be cured by standard procedure, as approved by the city engineer;
7. Be finished with a finishing machine approved by the city engineer, the machine shall be self-propelled, capable of striking off, consolidating and finishing the concrete of the consistency required to the proper crown and grade;.
8. Be air-entrained (five percent to seven percent) and field tested to verify this air-entrainment.
C. The subgrade shall be prepared properly so that after compaction it will conform to the alignment, grade, and cross-section shown on the approved plans. Soft and unstable material that will not compact shall be removed and replaced with material approved by the city engineer. The entire subgrade shall be compacted to not less than ninety-five percent of the standard laboratory density.
(Ord. 81-10 § 8.1 (B), 1980).