Numerical Study of Potential Indonesian Rubber for Elastomeric Base Isolators in Highly-Seismic Zones

Indonesia is located in high seismic zones. Therefore, earthquake dissipated devices such as elastomeric base isolator is needed to minimize building's damages when an earthquake occurs. In this study, a numerical two-stage analysis was carried out to evaluate the behaviour of elastomeric base isolators. First, elastomeric base isolators were modelled in the finite element software to obtain vertical and horizontal stiffness and damping values based on local rubber of mechanical properties that is obtained from the previous tests. Second, the values of vertical and horizontal stiffness and damping values were analysed in a case study of a ten-stories hospital building located in Padang, West Sumatra, Indonesia using nonlinear time history analysis of seven different ground motion values. The studied results showed that the structure with base isolators using a local rubber base material can reduce damage caused by the earthquake with an indication of an increase in time period, decreased base shear, and also a decrease in displacement of the structure. Therefore, the use of local rubber for elastomeric base isolators is promising a good future for the advancement of the construction industry in Indonesia.