One of the mitigation efforts in the context of reducing natural disasters, particularly
earthquakes, was by developing earthquake hazard maps in the form of acceleration maps in
bedrock and acceleration maps at the ground surface. The spectrum of acceleration at the ground
surface was very important for estimating earthquake risk, both against damage to building
structures, economic loss, and fatalities. The goal of this study was to calculate the earthquake
hazard at bedrock and at the ground surface, subsequently, calculate those amplification factors.
The calculation uses the Classical PSHA method with the help of OpenQuake software developed
by the Global Earthquake Model (GEM). The seismic sources and GMPEs used in this study were
derived from the latest data in the calculation of Indonesia Seismic Hazard Maps 2017. The
amplification factor obtained from the calculation is compared with the amplification factor
according to the National Standard for Earthquake Resistance Planning for Building and Non-
Building Structures of Indonesia (SNI 1726:2019) and ASCE 7-16. Calculations were carried out
in the area of Java Island, for the type of measurement of intensity for Peak Ground Acceleration
(PGA), short periods of 0.2sec SA(0.2) and for periods of 1.0sec SA(1.0) for 2475 year return
period. The results of the study show that most of the amplification factors at intensity
measurement of PGA, SA(0.2), and SA(1.0) corresponded to site coefficient in building code (SNI
1726:2019 and ASCE 7-16). The factor of amplification in PGA, the comparability was well suited
to all ranges of PGA at all site classes, except for the site class SD for 0.1g< PGA<0.2g, produced
the amplification factor about 13% lower than the amplification factor in the building code, and a
little bit higher in PGA range of 0.4g to 0.6g. The computation results in short period SA(0.2), the
amplification factor at almost all ranges of Ss values at all site classes was matching, except for the
SD site classes for 1.0g
Volume 12 | Issue 6
Pages: 3100-3112
DOI: 10.5373/JARDCS/V12I6/S20201275