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Effective Depth of Soil Column for Site Response Analysis of Deep Soil Sites
Background: Seismic site response analyses are routinely performed for shallow soil deposits. In the seismic site response studies, depth of input motion which is also called as the depth of half-space or bedrock and is one of the important parameters which influence the amplification and attenuation characteristics of any particular site. Objectives: Finding the exact location of bedrock for deep soil deposits is difficult and uneconomical. Hence, there is a need to identify the effective depth of soil column for deep soil sites to get representative site response parameters. Statistical Analysis: In the present study, recorded bedrock and surface earthquake data with soil profiles is used to identify the matching modulus and damping curves for widely available deep soil types and investigated the depth of half-space for site response study of deep soil sites. Eleven deep soil profiles having minimum depth of 100m and maximum depth of 800 m with different sets of recorded earthquake time histories from Kiban Kyoshin network are used for the study. Nonlinear site response analyses were carried out using the program DEEPSOIL. Suitable shear modulus and damping curves are identified by a parametric study of varying shear modulus and damping curves for a matching computed response spectrum with the measured response spectrum. Soil properties and model curves are frozen for each profile, which are further used to identify the depth of half space. Findings: Perfect matching layer having shear wave velocity and depth has been analysed, the study indicated that location of half-space is independent of depth factor. However, it is noticed in the study that computed response spectrum is close to the measured response spectrum when input is given for layer having shear wave velocity of 760 m/s±100.This layer represents a depth of half space for site response analysis of the deep soil column. Application: We can utilize the finding to perform for better accuracy and consistent results based on current findings and same can be used for site response studies.
Earthquake, Effective Depth of Soil Column, Input Motion, Response Spectrum, Site Response.
- NIED Strong Motion Seismograph Networks. Date Accessed: 01/01/2013. Available at: http://www.kyoshin.bosai.go.jp.
- Lee Hong-Sung, Yun Se-Ung, Park Duhee, Kim In-Tai. Estimation of Nonlinear Site Effects of Soil Profiles in Korea, Journal of the KGS. 2008 Mar; 24(3):13−23.
- Kumar A. Seismic Microzonation of Lucknow Based on Region Specific GMPE’s and Geotechnical Field Studies.PhD Thesis, Indian Institute of Science, Bangalore, 2013, p.1−32.
- Yu Huang, Weimin Ye, Zhuchang Chen. Seismic Response Analysis of the Deep Saturated Soil Deposits in Shanghai, Environmental Geology, 2009 Jan; 56(6):1163−69.
- Chen AT. Transmitting Boundaries and Seismic Response, Journal of Geotechnical Engineering. 1985 Feb; 111(2):174−80.
- Shean-Der Ni, Raj V. Siddharthan, John G. Anderson Characteristics of Nonlinear Response of Deep Saturated Soil Deposits, Bulletin of the Seismological Society of America. 1997 Apr; 87(2):342−55.
- LukeB. A., Matasovic N, Kemnitz M. Evaluating Seismic Response of Deep Sandy Soil Deposits, Bulletin of the Seismological Society of America. 2001 Dec; 91(6):1516−25.
- Hashash YMA, Park D. Non-linear One-Dimensional Seismic Ground Motion Propagation in the Mississippi Embayment, Eng. Geology, Amsterdam. 2001; 62:185−206.
- Manne A. Site Characterization and Ground Response Analysis for Vijayawada Urban. M. Tech Thesis, Earthquake Engineering Research Centre International Institute of Information Technology, Hyderabad, 2013.
- Seed HB, Idriss IM. Soil Moduli and Damping Factors for Dynamic Response Analyses, 1970 Report EERC 70-10, University of California, Berkeley, 1970.
- Electrical Power Research Institute, EPRI Guidelines for Determining Design Basis Ground Motions, Report No. EPRI TR-102293, Electrical Power Research Institute, Palo Alto, CA. Date Accessed: 1993 Nov. Available at: http://peer2.berkeley.edu/ngaeast_wg/wp-content/ uploads/2010/09/TR-102293-V2.pdf .
- Kokusho T. Cyclic Triaxial Test of Dynamic Soil Properties for Wide Strain Range. Soils and Foundations. 1980; 20:45−60.
- Seed HB, Sun JH. Implication of Site Effects in the Mexico City Earthquake of September 19, 1985 for EarthquakeResistance-Design Criteria in the San Francisco Bay Area of California. Report No. UCB/EERC-89/03, University of California, Berkeley, California, 1989.
- Vucetic M, Dobry R. Effect of Soil Plasticity on Cyclic Response, Journal of Geotechnical Engineering. 1991 Jan; 117(1):89−107.
- Seed HB, Wong RT, Idriss IM, Tokimatsu K. Moduli and Damping Factors for Dynamic Analyses of Cohesion less Soil, Journal of Geotechnical Engineering. 1986 Oct; 112(11):1016−32.
- Rollins KM, Evans M, Diehl N, Daily W. Shear Modulus And Damping Relationships for Gravels, Journal of Geotechnical and Geo-environmental Engineering, 1998 May; 124(5):396−405.
- Schnabel PB. Effects of Local Geology and Distance from Source on Earthquake Ground Motions. Ph.D. Thesis, University of California, Berkeley, 1973.
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