Time history shaking table test and seismic performance analysis of Industrialised Building System (IBS) block house subsystems

Abstract

An Industrialised Building System (IBS) block house was innovated from safe room or hurricane shelter designs developed by the Federal Emergency Management Agency (FEMA) in the United States. This IBS block house is made by a pre-cast reinforced concrete block system designed for the purpose to protect inhabitants from natural disasters and other unpredictable events. To investigate its dynamic seismic performance, time history testing on a shaking table with 1:5 downscaled block house column and sub-frame models were carried out. Sabah earthquake 2015 with a PGA of 0.126 g was used as the input signal for the time history shake table test. The dynamic response and structural behaviour of the models subjected to increasing seismic intensities were investigated via the analysing of time history test data and the observed cracking pattern of the scaled models. Different dynamic parameters such as acceleration, displacement, and hysteresis responses were evaluated. Based on all the analysed parameters, it can be concluded that no severe damages occurred on either model even when the vibration is increased to PGA 1.0 g. Both tested models were classified in a serviceability stage after the experiment. Dynamic Finite Element Analysis (FEA) of the models was also conducted. Compared with experimental results, the FEA results show good agreement with high R2 values of 0.9612 and 0.9771 for column and sub-frame models respectively. Hence, both time history testing and numerical analysis give a better understanding on the seismic performance and dynamic behaviour of IBS block house models under real time earthquake.