Development of a Land Subsidence Fragility Curve in Bandung Basin: a Preliminary Result

Abstract

Abstract Land subsidence has been historically detected and observed using the Global Positioning System (GPS) observations since the year 2000. At present, the Interferometric Synthetic Aperture Radar (InSAR) method is used to monitor the ongoing subsidence in the Bandung Basin. Due to its significant subsidence rate, reaching up to -20 cm/year, much evidence of its impact has been found in this area, e.g., damaged buildings. This study aims to develop a land subsidence fragility curve for damaged buildings, which is very beneficial for estimating economic losses and developing a risk map of land subsidence. The study area will be focused on Bandung District Area. Field surveys are carried out in areas that experience large land subsidence. More than 200 buildings are surveyed to estimate the damage to buildings due to land subsidence. Damage classification is divided into four categories: heavy, medium, low, and no subsidence. The classification is based on subsidence slope and cracks in the building. Survey results showed that damage occurred in all these categories. The modeling of the fragility curve shows the tendency of the increasing subsidence slope to cause more severe damage. However, this study only shows the preliminary result of a land subsidence fragility curve in the Bandung district and will be further investigated for optimal results.