STUDI MIKROTREMOR DENGAN METODE HVSR DI DISTRIK HERAM, KOTA JAYAPURA
DOI:
https://doi.org/10.31957/sains.v16i2.271Abstract
A study about microtremor was developed for Heram District, Jayapura City. This research was purposed to determine predominant frequency, predominant period and amplification of ground motion values based on microtremor recording. Direct measurement in field method was used for this research by using microtremor equipment. Microtremor signal recording was analysed by using HVSR (Horizontal to Vertical Spectral Ratio) method.
Microtremor analysis with HVSR method can use to determine ground layer characteristic. The result shows that predominant frequency, predominant period and amplification of ground motion values have variation at every measuring point. The lowest ground predominant period value is 0,0792 s, it means have higher predominant frequency value is 12,6325 Hz at measuring point IX (JPR 50) was located in around of church GPdI Ekklesia Padang Bulan, Hedam Village. The higher ground predominant periode value is 1,5725 s, it means have lowest predominant frequency value about 0,63594 Hz, at measuring point VII (JPR 48) was located in boarder of Yoka Village (Jayapura City) and Puai Village (Jayapura Regency). The higher ground motion amplification factor value is 2,46712 at measuring point VII (JPR 48) was located in boarder of Yoka Village (Jayapura City) and Puai Village (Jayapura Regency). The lowest amplification value is 1,33306 at measuring point IV (JPR 45) was located in around of Beautiful Pemda Housing, Waena Village.
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Key words : Microtremor, HVSR, frequency, periode, amplification,Hedam DistrictDownloads
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