Comparison of minimum thickness provisions for concrete beams in building codes and standards

Building codes and standards generally include provisions for deflection control of beams and slabs. These provisions usually include prescriptive methods for computing deflection as well as minimum thickness or span-depth limitations. In this paper, results of a study comparing minimum thickness provisions in several codes and standards including the Canadian (CSA A23.3) and American (ACI 318) provisions are presented. These results are in turn compared with results obtained based on a minimum thickness equation proposed by the authors. The results show that the CSA and ACI provisions have limited applica- tion and the proposed equation is recommended for adoption.