Analisis Amplifikasi Dan Indeks Kerentanan Seismik Di Kawasan Fmipa Ugm Menggunakan Metode HVSR

Abstract

Yogyakarta Special Region is a basin area that is composed of thick material deposits and is an active seismic area. Seismic waves that is trapped in thick sedimentary layers can cause severe damage to buildings in the earthquake event. Mapping of seismic hazard in the FMIPA UGM area is important because in that area many new buildings are built. Analysis of amplification and natural frequency was processed using the HVSR (Horizontal to Vertical Spectra Ratio) method, so that the seismic hazard index was generated in the study area. Based on the resuts of the study, It was found that the natural frequency (fo) value in the study area ranged from 0.636 -0.943 Hz, amplification (Ao) ranged from 2.196 – 3.446 and seismic hazard index (Kg) ranged from 5,291 -18,677. Based on the results of data processing obtained, it can be concluded that the subsurface of the FMIPA UGM region is composed of thick sedimentary layers with a thickness of ≥30m. This is associated with the DIY area which is arranged on basin with volcanic deposits. Based on the fo, Ao, and Kg values, it is known that the highest seismic values are found in the mathematics building of FMIPA UGM area. Keywords: HVSR method; fo; Ao; Kg.