ACI Code Deflection Requirements-Time for a Change?

Abstract

The paper presents a critical examination of the current American Concrete Institute's (ACI) Building Code Requirements for Structural Concrete (ACI 318-02) that controls flexural deflection in reinforced concrete members, with a focus on two-way non-prestressed slabs. Current code deflection criteria require the computation of deflections only to justify slab thicknesses less than those specified as minimum in the code. The paper recommends that the code should require deflection computations and conformance in all cases, and to eliminate or modify the minimum thickness criteria in the code.