Evaluasi Kinerja Struktural dari Base Isolator Berbasis Finite Element Modeling pada Struktur Bangunan Beton Bertulang Eksisting Akibat Beban Gempa

Abstract

This study aims to examine the structural behavior of existing buildings against earthquakes, analyze the effective dimensions of base isolator and investigate the performance of base isolator using finite element modeling (FEM). By limiting research to the Muhammadiyah 5 Junior High School building located in Surabaya. In this study, a reliability evaluation of building earthquake resistance will be carried out, as well as structural analysis to determine the effective type of base insulator and also compare structural performance using base isolator and without using base isolator (fixe base). The results of checking the existing structure model that the existing structure meets the reliability of earthquake resistance with SNI 1726,2019 regulations and meets the Strong Column-Weak Beam (SC-WB) concept with SNI 2847,2019 regulations. Results of structural performance level analysis based on ACSE 41-13 NSP, FEMA-440 and ATC-40 performance levels of existing building structures at Immediate Occupancy (IO). The results of the analysis showed that the HDRB base isolator type HH090X6R provide better performance, where the displacement efficiency reached 90.56% for the x direction and 95.87% for the y direction. The results of the analysis of the performance of the base isolator, that the HDRB base isolator HH090X6R experienced a displacement of 410.79 mm with a shear force of 865653 N. The results of the comparison of fix base and base isolator, with the structure using base isolator can increase the period of the structure by X direction by 34.68% and for Y direction by 56.33% of the structure without base isolator. With a structure using a base isolator, it can reduce the base shear force with for the X direction by 24.86% and for the Y direction by 26.12% from the structure without the base isolator.