Seismic Performance Evaluation of Essential Facilities Building in Dhaka City by Inelastic Time History Analysis

Abstract

Structures suffer significant inelastic deformation under a strong earthquake and dynamic characteristics of the structure change with time, so investigating the performance of a structure requires inelastic analytical procedures accounting for these features. Inelastic analytical procedures help to understand the actual behavior of structures by identifying failure modes and the potential for progressive collapse. Among the various inelastic procedures, the inelastic time history analysis is the most accurate method to predict the force and deformation demands at various components of the structure and hence, the application of inelastic time history analysis to evaluate the seismic performance of Secretariat Clinic Building located at the Secretariat of Government of Bangladesh, Dhaka is the focus of this thesis. Due to the unavailability of any strong ground motion record applicable for Dhaka city in the literature, artificial time history record generated based on response spectrum of Bangladesh National Building Code (BNBC,1993) has been used for analysis purpose in nonlinear finite element package, SeismoStruct-V5.2.2 (2011). The analysis reveals that the case study building possesses much greater stability in the longitudinal direction compared to the shorter direction in terms of energy dissipation capacity. It was also observed that storey sway mechanism develops in the bottom and top floors in both the directions under the input artificial time history records which may be attributed to the open ground floor for parking purposes and reduced steel area in columns at top floor from gravity load considerations.