Contribution of R/C Floor Slabs in Resisting Lateral Loads

Abstract

The effective width of slab to be used for the case of lateral loading has not been explicitly addressed in design codes. Ignoring the slab contribution to the flexural capacity of the beams leads to a significant underestimation in structural strength. It may also lead to a failure mechanism different than that anticipated. Tests were conducted on three one‐half scale reinforced concrete beamcolumn‐slab subassemblages to determine the influence of the torsional stiffness of the transverse beam elements on the effective width of slab participating as a tension flange to the longitudinal beam. The effect of initial damage due to loading in the transverse direction was also investigated for one of the models. All of the models were subjected to the same cyclic lateral load history. It was concluded that the effective width of slab was greater for the models with increased transverse torsional stiffness. The difference in strength among the models was larger at the earlier loading cycles. At the maximum load condition, the difference was less than 10%.