NONLINEAR DYNAMIC ANALYSIS OF TWO STOREY RC BUILDING MODEL

Abstract

Peninsular Malaysia lies in a low seismic zone, but its building structures had come across the concrete deterioration due to the seismic ground motion originated from far or near field. Notably, most of the building structures in this country are designed based on wind load only. Moreover, current practice to analyze or design a building such as FEMA 368 and EC8 underestimated the effect of repeated excitations. These guidelines only considered single vibrations to evaluate the framed structure. Therefore, the objective of this study was to assess the performance of private educational institute reinforced concrete building with generic 3D two storey frame structure under multiple seismic motions. Structural model was examined under series of earthquake motions which include pre-shock, main shock and aftershock scenario. Total of 7 seismic ground motions were selected to quantify the structural frame model by nonlinear dynamic time history analyses. Pseudo-dynamic ground motions were recorded on shaking table ranging from 0.18 g to 0.82 g were applied onto the building model for assessment. The outcome of this study has identified that the low-rise building model survived at higher PGA values. Moderate damages (0.25 ≤ DI < 0.40) were recorded after passing through multiple ground motions. Moreover, low seismic vibrations with large ground movement had caused ground floor storey act as soft storey. The study concluded that low rise building model had higher tendency to absorb lower to higher ‘g’ values and resist the earthquake loading due to the strength of framed structure.