A Comparison between Linear and Equivalent Linear Ground Response Analysis of the Sub-Soil of Ganakbari, Dhaka, Bangladesh

Abstract

Site-specific dynamic response analysis is the key step to ensure site safety against probable seismic hazards. One-dimensional(1-D) ground response analysis is widely used in engineering practices to predict the dynamic response of a site. This paper deals with the comparison of two frequency-dependent methods of 1-D ground response analysis-Linear and Equivalent Linear for ground response analysis of the sub-soil of Ganakbari, Savar, Dhaka. SPT N values were collected from the literature published earlier by various researchers. Shear wave velocity was determined by using a universal correlation of Shear wave velocity and Standard Penetration Test values.[6]. Analyses were performed using DEEPSOIL software for both linear and equivalent linear methods. As input motion, Kobe earthquake, Kocaeli earthquake, Northridge earthquake, Nahanni Earthquake, and Parkfield earthquake was used. The Response spectrum, the Peak Ground Acceleration, maximum strain, maximum stress ratio, and the amplification factor was determined and represented in this paper from both linear and equivalent linear analysis. Linear analysis results were compared with those of the equivalent linear method. Differences were found between the site responses predictions from linear and equivalent linear methods though both are 1-D frequency domain-based analysis methods.