Title: Seismic fragility analysis of a pile-supported wharf using capacity spectrum method

Authors: Dhara Shah; Bharat Shah

Addresses: Faculty of Technology, CEPT University, Kasturbhai Lalbhai Campus, University Road, Navrangpura, Ahmedabad-380009, Gujarat, India ' Applied Mechanics Department, L.D. College of Engineering, University Road, Navrangpura, Ahmedabad, 380015, Gujarat, India

Abstract: In this study, seismic fragility curves are derived for an existing pile-supported wharf, for three levels of earthquake motions, i.e., serviceability earthquake (SE), design-based earthquake (DBE) and maximum considered earthquake (MCE). The wharf is modelled using nonlinear platform along with soil structure interaction. Pushover analysis is performed to obtain its capacity curve. Site-specific spectrum is constructed and correspondingly seismic events are selected to represent demand. Using capacity spectrum method, maximum displacements at deck level are obtained to create response matrix. Damage states are established. Based on damage states and response matrix, fragility curves of wharf are constructed. It is observed that the port site has higher ground motions than specified in Indian standard. Indian standard thus underestimates the fragility of wharf, stating it to be functional for DBE and MCE. The site-specific spectrum clearly finds the wharf deficient, requiring urgent repairs to be serviceable and to resist future seismic events.

Keywords: seismic fragility analysis; fragility curves; pile supported wharf; site-specific spectra; capacity spectrum method; CSM; wharves; earthquakes; seismic motions; modelling; soil structure interaction; pushover analysis; warf damage; ground motion; India; ports.

DOI: 10.1504/IJEIE.2016.081754

International Journal of Earthquake and Impact Engineering, 2016 Vol.1 No.3, pp.311 - 331

Received: 14 May 2016
Accepted: 06 Jul 2016

Published online: 24 Jan 2017 *

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