Estimating Public Building Damages along the South Coasts of Sumatra Due to Impacts of Potential Tsunamis Generated from the Enggano and the Sunda Strait Megathrust Segments

Tsunamis are among the major disasters in Indonesia, including the south coasts of Sumatra. Among the anticipated tectonic megathrusts around this area is the Sunda Megathrust Segment, which could generate an earthquake at 8.9 Mw at the largest. However, a limited number of studies still investigated the potential damage to public buildings in this area due to tsunamis. This study aims to estimate building damages and economic losses on the Southern coasts of Sumatra (The Lampung Province) based on probable tectonogenic tsunamis generated from the Sunda Megathrust Segment. A series of tsunami numerical simulations were performed using the Cornell Multi Grid Coupled Tsunami (COMCOT) model using 6 layers of simulations. To estimate the impacts/damage ratios on the buildings, a set of tsunami fragility curves (which were later converted to a vulnerability curve) were adopted. Three types of buildings’ functions were included in the analysis, namely the government buildings (offices), educational buildings (schools), and healthcare facilities (hospitals and community clinics). The buildings’ structural types were classified based on Hazards United States (HAZUS) classifications. It is estimated that the Sunda Strait megathrust segment will cause severe impacts on 95 public buildings in Lampung should an-8.7 Mw earthquake occur from the segment and generate a tsunami.