Development of Nationwide Vs30 Map and Calibrated Conversion Table for Indonesia using Automated Topographical Classification

Abstract

Abstract.A nationwide Vs 30 map for Indonesia was developed based on automated topographic classification from 90-m grid digital elevation data and their correlation with Vs 30 . Automated topographic classification has been proposed by Iwahashi and Pike (2007) and a procedure to convert topographic class into Vs 30 maps has been developed by Imamura and Furuta (2015) based on Vs data from J-SHIS (Japan Seismic Hazard Information System). In order to be suitable for Indonesia, calibration work according to Imamura and Furuta's procedure should be conducted since the geotechnical conditions in Japan may not be the same as in Indonesia. This paper presents adjustment of the Vs 30 correlation by Imamura and Furuta to convert topographic class into Vs 30 and construct a Vs 30 map of Indonesia. This correlation was calibrated by using Vs data from BMKG (Indonesian Agency for Meteorological, Climatological, and Geophysics) as well as standard penetration test logs that were collected by the authors. Utilization of local field measurement data will certainly enhance the reliability of the Vs 30 map. The developed nationwide Vs 30 map will be very useful for disaster mitigation programs and for preliminary design of earthquake resistant buildings and infrastructure in Indonesia.

Methodology and Assessment of Proxy-Based Vs30 Estimation in Sichuan Province, China

“…This approach had been applied to characterize V s30 in California, United States, where each geomorphic type was assigned a mean V s30 value (Yong et al 2012) (Table 5). Irsyam et al (2017) also developed a nationwide V s30 map for Indonesia based on this approach from 90-m grid digital elevation data and their correlation with V s30 .…”

Development of Nationwide Surface Spectral Acceleration Maps for Earthquake Resistant Design of Bridges Based on National Hazard Maps of Indonesia 2017

“…The nationwide Vs30 map for Indonesia was obtained from [5]. It was developed based on the correlation between automated topographic classification by [9] and field Vs measurement by the Indonesian Agency for Meteorological, Climatological and Geophysics (BMKG).…”

“…Initially, [4] proposed a correlation table and a Vs 30 map for Indonesia, which was developed from Vs data from Japan and a previous correlation study [12]. Later, [5] conducted an analysis on 136 Vs data by BMKG and modified the correlation table that was previously proposed by [4], which yielded a new correlation and a new Vs 30 map based on Indonesian data. The Vs 30 map from [5] can be translated into a site class map in accordance with the criteria from SNI ( Figure 6).…”

“…The process was intended to obtain image files of Indonesia where every pixel has a value that is mathematically calculable. The proposed Vs 30 map of Indonesia by [5] in Figure 6 was also prepared in the same way and classified based on the Vs 30 criteria in [2]. Calculation of the amplification factors was based on Table 1, i.e.…”

“…The response spectra at surface for each city are presented in Figure 14. Figures 8 to 10 are amplification factor maps based on different variables: the site class maps from [5], the amplification factor table from [2], and the hazard at bedrock obtained from [3]. The expected output are maps with distinctive differences between one another, even though the F PGA map in Figure 8 and the Fa map in Figure 9 have similar visual profiles.…”