Reliability Study of Spectral Acceleration Designs Against Earthquakes in Bengkulu City, Indonesia
Published at : 25 Oct 2018
Volume : IJtech
Vol 9, No 5 (2018)
DOI : https://doi.org/10.14716/ijtech.v9i5.621
Mase, L.Z., 2018. Reliability Study of Spectral Acceleration Designs Against Earthquakes in Bengkulu City, Indonesia . International Journal of Technology. Volume 9(5), pp. 910-924
| Lindung Zalbuin Mase | Department of Civil Engineering, Faculty of Engineering, University of Bengkulu, WR. Supratman Rd, Kandang Limun, Muara Bangkahulu, Bengkulu 38371, Indonesia |
This paper presents a reliability study of spectral acceleration designs against earthquakes in Bengkulu City. Seismic Hazard Analysis of 1,968 events is performed to define the controlling earthquake event. Furthermore, the controlling earthquake is used as the scale factor to generate five input motions for one-dimensional seismic response analysis. The spectral accelerations resulting from the analysis are then compared to the updated spectral acceleration design. The results show that spectral acceleration designs are still able to cover the spectral acceleration of seismic response analysis. However, for the short period, the spectral acceleration of seismic response analysis exceeds the designed spectral acceleration. This is a matter of concern, since most of the building natural period in Bengkulu City is still categorized as short. In general, this study brings awareness to the design aspect considering earthquakes in Bengkulu City in order to reduce the possible impact on structures in the future.
Earthquakes; Seismic hazard analysis; Seismic response analysis; Spectral acceleration
It is known that earthquakes are a natural hazard which could trigger massive damage to a region such as Indonesia (Kanata et al., 2014; Sukanta et al., 2015). In 2000, a 7.90 Mw earthquake occurred in Bengkulu Province, Indonesia. It resulted in destructive damage, including collapsed buildings, fatalities, and injuries. The earthquake also triggered other catastrophic hazards, such as landslides and liquefactions in mountainous and coastal areas in Bengkulu. Seven years later, another big earthquake with a magnitude of 8.6 Mw hit the area (Mase, 2017a). This earthquake also resulted in structural damage and other geotechnical phenomena, such as ground failure and liquefaction. During both events, Bengkulu City suffered more serious impact than other cities and regencies in Bengkulu Province, due to the fact that the released energy of the earthquakes in 2000 and 2007 was very large (Mase, 2017a). Learning from these earthquake events, this earthquake study of Bengkulu Province is focused on Bengkulu City. Large earthquake events have not only happened in Bengkulu Province, but also in many other provinces in Indonesia, such as Nangroe Aceh Darussalam in 2004, North Sumatra in 2005, and West Sumatra in 2009. Those earthquakes also triggered massive structural damage, which revealed that the seismic design code in Indonesia needs to be evaluated. Considering these earthquake events, the Indonesian Government revised the previous seismic design code (SNI 03-1726-2002) to a new one (SNI 03-1726-2012). The updated seismic design code is now becoming the reference for local engineers in Indonesia for construction design (Mase & Somantri, 2016), and should be considered as design practice for buildings all over Indonesia.
In this study, a seismic response analysis due to earthquakes is presented. The study aims to check the reliability of the updated seismic design code (SNI 03-1726-2012) with regard to earthquakes in Bengkulu. The ground motion is propagated from the surface of engineering bedrock through the soil layer. At the ground surface, it is further transferred to the spectral acceleration curves, which are compared to the updated seismic design code. In addition, the amplification factor between the propagated ground motion and the ground motion analyzed at the ground surface is also presented. In general, the study is expected to provide better understanding of seismic ground response analysis in Bengkulu City, as well as to provide suggestions to local engineers in consideration of spectral acceleration design for construction design in Bengkulu City.
The results show that the designed spectral
acceleration is still able to cover the spectral acceleration resulting from
the wave propagation of the controlling earthquake. However, for Tn < 0.2s, 0.2s<
Tn < 0.7s, the
designed spectral acceleration for three site classes (soft soil, medium soil
and stiff soil) are exceeded by the spectral acceleration of the seismic
response analysis. In addition, the great case needs to be taken when
designing earthquake loads for the buildings. This study also brings a
recommendation to study liquefaction in the investigated sites, since the sandy
soils are generally found in the investigated sites. The numerical analysis as
performed by Mase et al. (2017a) and the experimental study as performed by
Mase (2017b) can be performed in the future.
The author would be grateful for the earthquake data from National Agency for Meteorology, Climatology and Geophysics, or BMKG, which are used in this study.
Abrahamson, N.A., Silva W.J., Kamai, R., 2014. Summary of the ASK14 Ground Motion Relation for Active Crustal Regions. Earthquake Spectra, Volume 30(3), pp. 1025–1055.
Atkinson, G.M., Boore, D.M., 2003. Empirical Ground-Motion Relations for Subduction Zone Earthquakes and Their Application to Cascadia and Other Regions. Bulletin of the Seismological Society of America, Volume 93(4), pp.1703–1729
Badan Meteorologi Kimatologi dan Geofisika (BMKG), 2017. Earthquake Data in 2000–2009. BMKG. Available online at http://www.bmkg.go.id [in Bahasa]
Boore, D.M., Stewart, J.P., Seyhan, E., Atkinson, G.M., 2014. NGA-West 2 Equations for Predicting PGA, PGV, and 5%-Damped PSA for Shallow Crustal Earthquakes. Earthquake Spectra, Volume 30(3), pp. 1057–1085
Campbell, K.W., Bozorgnia, Y., 2014. NGA-West2 Ground Motion Model for the Average Horizontal Components of PGA, PGV, and 5% Damped Linear Acceleration Response Spectra. Earthquake Spectra, Volume 30(3), pp. 1087–1115
Chiou, B,S-J., Youngs, R.R., 2014. Update of the Chiou and Youngs NGA Model for the Average Horizontal Component of Peak Ground Motion and Response Spectra. Earthquake Spectra, Volume 30(3), pp. 1117–1153
Dahle, A., Climent, A., Taylor, W., Bungum, H., Santos, P., Ciudad Real, M., Linholm, C., Strauch, W., Segura, F., 1995. New Spectral Strong Motion Attenuation Models for Central America. In: Proceedings of the Fifth International Conference on Seismic Zonation, Nice, 17–19 October, France
Google Earth, 2017. Bengkulu Province Region. Available online at http: www.google.co.id
Hwang, H., Huo, J.R., 1997. Attenuation Relations of Ground Motion for Rock and Soil Sites in Eastern United States. Soil Dynamics and Earthquake Engineering, Volume 16(6), pp. 363–372
Idini, B., Rojas, F., Ruiz, S, Pastén, C., 2017. Ground Motion Prediction Equations for the Chilean Subduction Zone. Bulletin of Earthquake Engineering, Volume 15(5), pp. 1853–1880
Ishihara, K., Tatsuoka, F., Yasuda, S., 1975. Undrained Deformation and Liquefaction of Sand under Cyclic Stresses. Soils and Foundation, Volume 15(1), pp. 29–44
Kanata, B., Zubaidah, T., Ramadhani, C., Irmawati, B., 2014. Changes of the Geomagnetic Signal Linked to Tohoku Earthquake on March 11th 2011. International Journal of Technology, Volume 5(3), pp. 251–258
Kataoka, S., Satoh, T., Matsumoto, S., Kusakabe, T., 2006. Attenuation Relationships of Ground Motion Intensity using Short Period Level as a Variable. Doboku Gakkai Ronbunshuu A, Volume 62(4), pp. 740–757
Kinasih, I.P., Wiriasto, G.W., Kanata, B., Zubaidah, T., 2014. Lesser Sunda Islands Earthquake Inter-occurrence Times Distribution Modeling. International Journal of Technology, Volume 5(3). pp. 242–250
Lu, J., Elgamal, A., Yang, Z., 2006. Cyclic1D: A Computer Program for Seismic Ground Response, Report No. SSRP-06/05, Department of Structural Engineering, University of California, San Diego, La Jolla, CA, USA
Mase L.Z., 2017a. Liquefaction Potential Analysis along Coastal Area of Bengkulu Province due to the 2007 Mw 8.6 Bengkulu Earthquake. Journal of Engineering and Technological Sciences, Volume 4(6), pp. 721–736
Mase L.Z., Tobita, T., Likitlersuang, S., 2016. Liquefaction Potential in Chiang Rai Province, Northern Thailand due to the 6.8 Mw Earthquake on March 24, 2011, In: Proceeding of the 36 conference on earthquake engineering, JSCE, paper No. 0905 (CD ROOM), Kanazawa, 17–18 October, Japan.
Mase L.Z., Tobita, T., Likitlersuang, S., 2017. One-dimensional Analysis of Liquefaction Potential: A Case study in Chiang Rai Province, Northern Thailand. Journal of Japanese Society of Civil Engineers, Ser A1 (Structural Engineering/Earthquake Engineering), Volume 73(4) pp. I_135–I_147
Mase, L. Z., Likitlersuang, S., Tobita, T. 2018a. Non-linear Site Response Analysis of Soil Sites in Northern Thailand during the Mw 6.8 Tarlay Earthquake. Engineering Journal, 22(3), 291–303
Mase, L. Z., Likitlersuang, S., Tobita, T. 2018b. Analysis of Seismic Ground Response Caused During Strong Earthquake in Northern Thailand. Soil Dynamics and Earthquake Engineering, Volume114, pp. 113–126
Mase, L.Z., 2010. Analysis of Damage Intensity Based on MMI and Frequency of Earthquake Occurrence in Province of Bengkulu, Bachelor Thesis, University of Bengkulu, Bengkulu, Indonesia [in Bahasa]
Mase, L.Z., 2017b. Shaking Table Test of Soil Liquefaction in Southern Yogyakarta. International Journal of Technology, Volume 8(4), pp. 747–760
Mase, L.Z., Somantri, A.K., 2016. Development of Spectral Response Design for Bengkulu City Based on Deterministic Approach. In: Proceeding of the 20th Annual Meeting of Indonesian Society for Geotechnical Engineering. 15-16 November, Jakarta, Indonesia, pp. 147–152
National Earthquake Hazards Reduction Program (NEHRP), 1998. Recommended provisions for seismic regulation for new buildings and other structures, 1997 Edition, FEMA 302, USA
Parra, E., 1996. Numerical Modelling of Liquefaction and Lateral Ground Deformation Including Cyclic Mobility and Dilation Response in Soil Systems, PhD Thesis, Rensselaer Polytechnic Institute, New York, USA
Pender, M.J., Orense, R.P., Wotherspoon, L.M., Storie, L.B., 2016. Effect of Permeability on the Cyclic Generation and Dissipation of Pore Pressures in Saturated Gravel Layers. Geothechnique, Volume 66(4), pp. 313–322
Pezeshk, S., Zandieh, A., Tavakoli, B., 2011. Hybrid Empirical Ground-Motion Prediction Equations for Eastern North America using NGA Models and Updated Seismological Parameters. Bulletin of the Seismological Society of America, Volume 101(4), pp.1859–1870
Prevost, J.H., 1985. A Simple Plasticity Theory for Frictional Cohesionless Soils. International Journal of Soil Dynamics and Earthquake Engineering, Volume 4(1), pp. 9–17
Refrizon, Hadi, A.I., Lestari, K., Octari, T., 2013. Analysis of Peak Ground Acceleration and Seismic Vulnerability in Ratu Agung Bengkulu City, In: Proceeding of Semirata FMIPA UNILA, Lampung, 10-12 May, Indonesia [in Bahasa]
Reiter, L., 1990. Earthquake Hazard Analysis: Issues and Insight, Columbia University Press, New York, USA
Shoushtari, A.V., Adnan, A.B., Zare, M., 2016. On the Selection of Ground-Motion Attenuation Relations for Seismic Hazard Assessment of the Peninsular Malaysia Region due to Distant Sumatran Subduction Intraslab Earthquakes. Soil Dynamics and Earthquake Engineering, Volume 82(1), pp. 123–137
SNI 03-1726-2002, 2002. Standard of Earthquake Resistance Design for Building, Ministry of Public Works, Jakarta, Indonesia [in Bahasa]
SNI 03-1726-2012, 2012. Standard of Earthquake Resistance Design for Building, National Standardization Agency, Jakarta, Indonesia [in Bahasa]
Sukanta, I.N., Prakoso, W.A., Ilyas, T., Irsyam, M., 2015. Development of an Extended Hara Model for Mw Determination of Moderate-Magnitude Earthquakes. International Journal of Technology, Volume 6(3), pp. 380–387
Tjokrodimuljo, K., 2000. Earthquake Engineering. Department of Civil Engineering, Gadjah Mada University, Yogykarta, Indonesia [in Bahasa]
Toro, G.R., 2002. Modification of the Toro et al. (1997) Attenuation Equations for Large Magnitudes and Short Distances. Technical Report Risk Engineering Inc., pp. 4-1–4-10
Wood H.O., Neumann, F., 1931.
Modified Mercalli Intensity of 1931. Bulletin
of the Seismological Society of America, Volume 21(4), pp. 277–283
Yang, Z., 2000. Numerical
Modelling of Earthquake Site Response
Including Dilation and Liquefaction, PhD Dissertation, Columbia University, New York, USA