Microtremor analysis to evaluate BMKG region III building, Bali, Indonesia

Subject Areas : Geophysics

Muh  Sarkowi ¹ (Geophysical Engineering, Engineering Faculty, Universitas Lampung, 35145, Bandar Lampung, Lampung, Indonesia)
Rahmat  Wibowo ² (Geophysical Engineering, Engineering Faculty, Universitas Lampung, 35145, Bandar Lampung, Lampung, Indonesia)
Ida Bagus  Yogi ³ (Geophysical Engineering, Engineering Faculty, Universitas Lampung, 35145, Bandar Lampung, Lampung, Indonesia)
Mahmud  Yusuf ⁴ (Research & Development Center BMKG, Jakarta, Indonesia,)
Yohana  Boka ⁵ (Geophysical Engineering, Industry and Production Technology Department, Institut Teknologi Sumatera, 35365, South Lampung, Lampung, Indonesia)

Received: 2020-12-21 Accepted : 2021-05-05 Published : 2021-05-05

Keywords: vulnerability building, Natural frequency, resonance, Microtremor, Bali,

Abstract :

Bali Island has experienced more than 6 significant earthquakes (magnitude > 6) since 1815, which caused extensive damage to buildings and casualties. The microtremor data analysis in the building of Indonesian meteorology, climatology and geophysics agency (BMKG) Region III Denpasar aims to reduce the risk of building damage and casualties due to the earthquake. The analysis was conducted by measuring microtremor and processing the data to obtain the natural frequency of the soil (f0s HVSR) and building (f0b HVSR), resonance, soil (Kg), and building vulnerability index (Kb) so that the safety of the building can be known in the event of an earthquake. The processing and analyzing results the characteristics of microtremor data get the f0b has a greater value than the f0s value so that the building is relatively safe from resonance. The resonance value of the building with the ground has an (R) value of 6.67% - 13.3%, with an average resonance value of 8.89% which is included in the medium resonance. The location of the building is in an area with a Kg of 8.20 – 10.81, which is included in the category of low to moderate soil vulnerability index, and the Kb has a value of 0.4827x10-6 – 7.9771x10-6, with the first floor having an index highest vulnerability. The f0s, f0b, R, Kg, and Kb show that the building is in the safe category in the event of an earthquake.

References:

1. Akkaya İ (2020) Availability of seismic vulnerability index (Kg) in the assessment of building damage in Van, Eastern Turkey. Earthquake Engineering and Engineering Vibration, 19(1): 189–204.


2. Abdialim S, Hakimov F, Kim J, Ku T, and Moon SW (2021) Seismic site classification from HVSR data using the Rayleigh wave ellipticity inversion: a case study in Singapore. Earthquakes and Structures 21(3):231-8.


3. Wangsadinata W (2002) Standar Perencanaan Ketahanan Gempa untuk Struktur Bangunan Gedung (SNI 1726-2002). National Standardization Agency, Jakarta.


4. Bekler T, Demirci A, Ekinci YL, Büyüksaraç A (2019) Analysis of local site conditions through geophysical parameters at a city under earthquake threat: Çanakkale, NW Turkey. Journal of Applied Geophysics, 163: 31-39.


5. Büyüksaraç A, Bektaş Ö, Yılmaz H, Arısoy MÖ (2013) Preliminary seismic microzonation of Sivas city (Turkey) using microtremor and refraction microtremor (ReMi) measurements. Journal of Seismology 17(2): 425–435.


6. Daryono, Sutikno, Sartohadi J, Dulbahri,  Brotopuspito KS (2009) Efek tapak lokal di Graben bantul berdasarkan pengukuran mikrotremor. International Conference Earth Science and Technology, Yogyakarta: 6-7.


7. Daryono (2011) Identifikasi Sesar Naik Belakang Busur (Back Arc Thrust) Daerah Bali Berdasarkan Seismisitas dan Solusi Bidang Sesar. Artikel Kebumian, Badan Meteorologi Klimatologi dan Geofisika 5 January.


8. Fergany E, Omar K (2017) Liquefaction potential of Nile delta, Egypt. NRIAG Journal of Astronomy and Geophysics 6(1): 60–67.


9. Gallipoli MR, Mucciarelli M, Castro RR, Monachesi G,  Contri P (2004) Structure, soil-structure response and effects of damage based on observations of horizontal-to-vertical spectral ratios of microtremors. Soil Dynamics and Earthquake Engineering 24(6):487–495.


10. Gosar A (2007) Microtremor HVSR study for assessing site effects in the Bovec basin (NW Slovenia) related to 1998 Mw5.6 and 2004 Mw5.2 earthquakes. Engineering Geology 91(2-4):178-93.


11. Gosar A, Rošer J, Motnikar BŠ,  Zupančič P (2010) Microtremor study of site effects and soil-structure resonance in the city of Ljubljana (central Slovenia). Bulletin of Earthquake Engineering 8(3): 571–592.


12. Hadiwidjojo PMM, Samodra H, Amin TC (1998) Geological Map of The Bali Sheet. Geological Research and Development Centre of Indonesia, Bandung 1(1):12-21 .


13. Herak M (2008) ModelHVSR—A Matlab tool to model horizontal-to-vertical spectral ratio of ambient noise. Computers and Geosciences 34: 1514–1526.


14. Kanai K (1983) Engineering Seismology. University of Tokyo Press.


15. Konno K, Ohmachi T (1998) Ground-motion characteristics estimated from spectral ratio between horizontal and vertical components of microtremor. Bulletin of the Seismological Society of America 88(1): 228–241.


16. Kurniawan R, Eva MN, Marjiyono M, Sismanto S (2017) Pemetaan daerah rawan resiko gempa bumi menggunakan metode hvsr di kotamadya denpasar dan sekitarnya, bali. Kurvatek 2(1): 21–30.


17. Lantada N, Pujades LG, Barbat AH (2009) Vulnerability index and capacity spectrum based methods for urban seismic risk evaluation. A comparison. Natural Hazards 51(3): 501–524.


18. Moon SW, Subramaniam P, Zhang Y, Vinoth G, Ku T (2019) Bedrock Depth Evaluation from Microtremor Measurement at Weathered Granite Formation in Singapore. Journal of Applied Geophysics 171:103866.


19. Mucciarelli M, Herak M, Cassidy J (2007) Increasing Seismic Safety by Combining Engineering Technologies and Seismological Data 148.


20. Murdiantoro RA, Sismanto S, Marjiyono M (2016) Pemetaan Daerah Rawan Kerusakan Akibat Gempabumi Di Kotamadya Denpasar dan Sekitarnya dengan Menggunakan Analisis Mikrotremor, Studi Kasus : Gempabumi Seririt 14 Juli 1976. Jurnal Fisika Indonesia 20(2):36-41.


21. Nakamura Y (1989) A Method For Dynamic Characteristic Estimation Of Surface. Quarterly Reports of The Railway Technical Research Institute, 9.


22. Nakamura Y (1997) Seismic vulnerability indices for ground and structures using microtremor. World Congress on Railway Research, 1–7.


23. Nakamura Y (2000) Clear identification of fundamental idea of Nakamura's technique and its applications. Proceedings of the 12th World Conference Earthquake Engineering, Auckland, New Zeland: 1-8.


24. Över S, Büyüksaraç A, Bektaş Ö, Filazi A (2011) Assessment of potential seismic hazard and site effect in Antakya (Hatay Province), SE Turkey. Environmental Earth Sciences 62(2): 313-326.


25. Prakosa PT, Ibad MI, Kafi MS, Burhanudin MA,  Rahmania A (2015) Earthquake Microzonation and Strength Building Evaluation at Gelora Bung Tomo Stadium Surabaya Using Micro-Tremor Method. Proceedings of the 2014 International Conference on Physics and Its Applications 1: 14–20.


26. Pratama IPD, Priyanto DK,  Negara PKGA (2020) Ambient Seismic Noise Analysis of Nyepi Cellebration Day in Denpasar , Bali Using Horizontal-to-Vertical Spectral Ratio ( HVSR ). Jurnal Geofisik 18(1):23-6.


27. Sato T, Nakamura Y, Saita J (2008) the Change of the Dynamic Characteristics Using Microtremor. World Conference on Earthquake Engineering, October 12-17.


28. Sungkono, Warnana DD, Triwulan, Utama W (2011) Evaluation of Buildings Strength from Microtremor Analyses. International Journal of Civil and Environmental Engineering IJCEE-IJENS 6:8.


29. Tokimatsu K (1995) Geotechnical site characterization using surface waves. 1st Intl. Conf. Earthquake Geotechnical Engineering: 1333–1368.


30. Triwulan, Utama W, Warnana, DD, Sungkono (2010) Vulnerability Index Estimation for Building and. International Seminar on Applied Technology, Science and Arts: 1–5.


31. Wulandari A, Suharno S, Rustadi R, Robiana R (2018) Pemetaan mikrozonasi daerah rawan gempabumi menggunakan metode hvsr daerah painan sumatera barat. Jurnal Geofisika Eksplorasi 4(1):31-45.