Dynamic Gravity Load Collapse of Low-ductility RC Frames Subjected to the 1999 Chi-Chi Near-fault Earthquake Records

Dynamic Gravity Load Collapse of Low-ductility RC Frames Subjected to the 1999 Chi-Chi Near-fault Earthquake Records

During the September 21(local time) 1999 Chi-Chi Taiwan earthquake, a large number of older buildings built before 1982 sustained severe damage and many others suffered from complete failure. These old buildings, having low ductility RC columns, are known to have poor seismic performance in terms of ductility and energy dissipation capacity during severe seismic events. Therefore, it is the main concerns of structural engineers and, at the same time, benefit of building owners how to retrofit these old buildings to match more strict requirements of the next generation building code to get better odds to survive probable future earthquake events. To reach this goal, dynamic nonlinear behaviors of these low ductility columns must be first thoroughly studied. Shake table tests using near-fault input motions, therefore, were conducted to yield experimental data on structural post-peak behaviors involved in global collapse mechanism. In addition, image processing technique was employed in this study to monitor large displacements of test specimens.