Structural evaluation of existing buildings using surface ground motions

Abstract

Research on new seismic sources and seismic data has already performed in 2016 to 2017. Four new shallow crustal fault sources were observed surrounding the city of Semarang, the capital city of Central Java Province, Indonesia. The seismic parameters related with the seismic mechanism (reverse fault) and the maximum magnitude prediction (6.5 Mw) for each seismic sources was also released based on the 2017 research. Following this research, structural evaluation especially for buildings that was designed and constructed based on 2002 Indonesian Seismic Code was also performed. The spectral acceleration design of 2002 seismic code was developed based on subduction source located at the southern of Java island. The structural evaluation was performed for all university buildings located at the Diponegoro University. This paper describes the seismic hazard analysis results of the university area and an example results of building evaluation located at this area. The seismic hazard analysis was performed based on the 2002 Probability Seismic Hazard Analysis/PSHA of the code and the Deterministic Seismic Hazard Analysis (DSHA) of four seismic sources. Two different structural analysis were conducted for all buildings such as structural deformation and drift ratios. Based on the seismic hazard analysis results, all buildings located at the university area were strong enough in resisting the surface ground motion (Peak Ground Acceleration/PGA) due to shallow crustal fault earthquake scenarios having magnitude 6.5 Mw. The buildings deformation and drift ratios calculated using 2002 Indonesian seismic code are greater compared to the same analysis calculated based on deterministic model of shallow crustal fault sources.