نسبت تغییر مکان غیر الاستیک برای سازه های در معرض زلزله های پالسگونه حوزه نزدیک

In this paper, the results of a statistical study on inelastic displacement ratio for structures subjected to pulse like near fault ground motions were presented. This study is important because, the results can used for evaluating inelastic displacement demand of structures with known lateral stiffness and strength subjected to near fault ground motions. Inelastic displacement ratio were computed from the response of single-degree-of-freedom systems having 6 level of strength reduction factor when subjected to 61 pulse like near fault records. The influence of period of vibration normalized by period of peak spectral displacement, strength reduction factor, period associated with velocity pulse TP, earthquake magnitude and distance to the source, post-yield stiffness and hysteresis behavior of structure on inelastic displacement are evaluated. Results indicate that strength and stiffness degrading in short period region increase inelastic displacement demands. Finally, a simply equation for estimate the mean of the inelastic displacement ratio for structures subjected to pulse like near fault ground motions is proposed.