1904.3 Concrete properties.
BC § 1904.3
Concrete mixtures shall conform to the most restrictive requirements of ACI 318, Section 19.3.2, based on the exposure classes assigned in Section 1904.2 of this chapter. Exception: For occupancies and appurtenances thereto in Group R occupancies that are in buildings less than four stories above grade plane, normal-weight aggregate concrete is permitted to comply with the requirements of Table 1904.3 of this chapter in lieu of the requirements of ACI 318, Table 19.3.2.1. Table 1904.3Minimum Specified Compressive Strength (f 'c) Location of Concrete Construction Minimum Specified Compressive Strength(f 'c at 28 days, psi)Basement walls, foundation walls, exterior walls and other vertical concrete surfaces, basement slabs, interior slabs on grade except for garage floor slabs, and foundations not exposed to the weather3,000 aDriveways, curbs, walks, patios, porches, carport slabs, steps and other flatwork exposed to the weather, and garage floor slabs3,500 bStructural concrete exposed to weather4,500 For SI: 1 pound per square inch = 0.00689 MPa. a. Concrete in these locations that can be subjected to freezing and thawing during construction shall be of air-entrained concrete in accordance with Section 1904.2. b. Concrete shall be air entrained in accordance with Section 1904.4.1.
