EFFECT OF SLAB ON INELASTIC RESPONSE OF R C BUILDING/

Tests on beam-to-column connections have shown that the presence of a slab significantly increases the flexural resistance of the beam under bending, which causes tension in the slab. The analytical beam models should, therefore, be able to simulate this behavior in the inelastic dynamic analysis of buildings. A multispring beam model modified to r ecognize different strengths and stiffnesses of the beam in the slab-i n-tension and slab-in-compression directions of bending is presented. Analysis of a typical multistory building with the proposed method of beam-slab representation indicates significant increases in story acce lerations and base shear. The curvature ductility demand at the two en ds of the beam is affected by the increasing participation of the slab . Furthermore, by recognizing the increased capacity of the beam-slab section, the demands placed on the columns can be estimated more reali stically to assure a strong-column and weak-beam mechanism.