EVALUATION OF TALL STEEL STRUCTURES WITH DUAL SYSTEM (SMRF RC SHEAR WALL) IN NEAR-FIELD GROUND MOTIONS BY PERFORMANCE BASED DESIGN METHOD

摘要

This paper discusses performance of tall steel structures with dual system (comprised of SMRFs and Intermediate RC shear walls) in near-fault ground motions according to acceptance criteria introduced in FEMA356 and ATC40. Achieving this purpose and in comparison with far-fault ground motions and evaluating acceptability of push-over analyses in performance based design method, some nonlinear time history analyses under near-field and far-field records and some nonlinear static analyses are performed. There after acceptance criteria of structures is checked. The results show that despite of appropriate performance of dual system under far- fault excitations, structural performance is not acceptable under near-fault ground motions because of inadmissible story drifts. Deficiency of Iranian code (Standard No. 2800) in exhibition of critical load combination for column's seismic design and inadequacy of push-over analysis in demonstrating tall buildings performance are other results of this study.