Hasan MOGHADDAM - Professor, Sharif University of Technology, Tehran, Iran
Mojtaba HARATI - Lecturer, University of Science and Culture, Rasht, Iran

Nowadays, RC structural sy stems are being used in construction industry w orldwide. The observed response of medium rise building, based on post-earthquake damage assessment reports, during the latest earthquakes in the USA, Chile, Me xico and Japan have indicated that buildings in cluding shear walls and dual structural systems behave considerably better during strong shaking. The viewp oint that shear walls are inherently brittle is still held in many countries (correspondingly in the codes) as a c onsequence of failures in poorly detailed RC walls. In this investigation, several RC frames, with and w ithout shear walls, are designed according to the seismic codes, and then their nonlinear duplicates are ex posed to a set of severe quakes. The time history nonlinear analyses results of these prototypes are then us ed to probe the effect of the existence of shear walls through using performance based design method. It is concluded that in general the existence of shear walls result s in a noteworthy decline in the seismic deformation demand. These changes happened in both the plastic rotations in main RC structural members and t he inter story drifts ratio. Hence, it is concluded that the exist ence of shear walls mostly improves the safety of medium rise RC frames within the assessment framework of performance based design codes such as ASCE4 1 (2006).

Moment Resisting Frame (Mrf), RC Shear Wall, Performance Based Design.