2d nonlinear site response analysis of shallow bedrock sites using integrated subsurface profiles

Chandran, D and Anbazhagan, P (2020) 2d nonlinear site response analysis of shallow bedrock sites using integrated subsurface profiles. In: Annals of Geophysics, 63 (4). pp. 1-23.

PDF ann_geo_63-04_1-23_2020.pdf Restricted to Registered users only Download (8MB) | Request a copy

Abstract

In this study, an attempt has been made to generate the subsurface profiles using integrated geophysical approach and a site-specific 2-D nonlinear site response analysis at shallow bedrock sites in Peninsular India. The site selected for the study is Tarapur, India in which three survey lines were selected for the sub-surface mapping. The subsurface profiling of these three locations was done by an integrated geophysical approach by carrying out Multichannel Analysis of Surface Waves-2D survey, Ground Penetrating Radar survey, and conventional drilling borehole and measurement of Standard Penetration Test N values. Thirteen intraplate recordings from all around the world are selected for the site response analysis. The subsurface profiles generated by the integrated geophysical approaches are modeled in FLAC-2D nonlinear module and site response parameters are estimated. Further 1D site response analyses are carried out at selected points in 2D profiles using the program DEEPSOIL and the 2D site response results are compared. Results of site response analysis are expressed in terms of short-period amplification factor (Fc) and long period amplification factor (Fs) and the results show that the 2D geometry of sub-surface is more sensitive to the higher frequency content of ground motion especially for subsurface with more heterogeneities. Also, a parametric study has been done on a synthetic 2D profile to quantitatively evaluate the effect of different ground motion characteristics like amplitude and frequency content on 2D site response analysis. The parametric study shows that underground heterogeneity is very sensitive to the ground motions with high-frequency content and low amplitude. © 2020 the Istituto Nazionale di Geofisica e Vulcanologia. All rights reserved.

Item Type:	Journal Article
Publication:	Annals of Geophysics
Publisher:	Editrice Compositori s.r.l.
Additional Information:	The copyright of this article belongs to Editrice Compositori s.r.l.
Keywords:	amplitude; bedrock; finite element method; ground motion; ground penetrating radar; nonlinearity; penetration test; response analysis; seismic response, India; Maharashtra; Tarapur
Department/Centre:	Division of Mechanical Sciences > Civil Engineering
Date Deposited:	16 Nov 2020 05:08
Last Modified:	16 Nov 2020 05:08
URI:	http://eprints.iisc.ac.in/id/eprint/66697

Actions (login required)

View Item