Model validation of carbon-fiber and glass-fiber reinforced elastomeric isolators using finite element method

Abstract

Fiber Reinforced Elastomeric Isolators (FREI) is a base isolation innovation for low-rise buildings suitable for developing countries with high earthquake intensity, for instance, Indonesia. The extension of the basic natural fundamental period by FREI will result into a reduction in floor acceleration when an earthquake occurs, thereby it will be reducing the inter-story drift movement in the superstructure. The FREI mass structure is lighter for low-rise buildings due its components consist of a layer of rubbers and a sheet of fibers. This study investigated numerically the use of fiber materials (glass and carbon fibers) for FREI reinforcement using ABAQUS program. The analysis results were evaluated based on mechanical characterization, including vertical and horizontal stiffness, effective horizontal stiffness, and damping ratio. The mechanical characterization in numeric research will be compared with experimental research as a research validation to ensure the input material variables are reliable and valid. Based on the analysis of numeric research results, CFREI and GFREI indicated that hysteresis curves and mechanical characterization were quite close to experimental research. Calculation of mechanical characterization in CFREI and GFREI refers to the regulations of BS_EN_1337:2005 and BS_EN_15129:2009. A deviation of mechanical characterization on numeric research of both specimens against the experimental research, including effective horizontal stiffness and damping ratio, indicated a fairly small deviation with less than 10%. The deviation between the maximum effective horizontal stiffness in CFREI and GFREI was 4.733% and 0.672% respectively, meanwhile the maximum damping ratio in CFREI and GFREI indicated the larger deviation that was 0.812% and 8.679% individually.