Seismic response assessment of reinforced concrete structures based on displacement, force and energy criteria, considering soil-structure interaction

Abstract

ABSTRACTSeveral 3D nonlinear models consisting RC moment-frame and dual frame-wall systems were developed using generic structures’ algorithm. A realistic nonlinear modelling of ductile behaviour for RC elements was performed in combination with the sub-structuring method to take into account SSI. Nonlinear pushover and nonlinear response history analyses were conducted to evaluate displacement-based ductility and damage indices of the structure, normalised stories shear forces and overturning moments, normalised story inertial forces and kinetic energy, as well as foundation rocking motion. The effects of different paramters including the foundation flexibility, the seismic force-resisting system, directivity effect of near-filed earthquakes, story strength distribution, uni-directional vs. bi-directional excitation, and number of stories on the structures' seismic respones were considered. The results indicated the seismic response values were noticeably affected by the directionality factor which is itself influenced by the ratio of pulse period to the structure period for near-field earthquakes. Besides, the distributions of the responses along the height of the structure was mainly controlled by both the lateral resisting system type and number of stories. Both of these parameters also had a significant effect on the role of SSI in modifying the ductility factors and the foundation rocking motion.