Sharif University of Technology Scientia Iranica 1026-3098 28 4 2021 08 01 Stochastic nonlinear ground response analysis: A case study site in Shiraz, Iran 2070 2086 22130 10.24200/sci.2021.55997.4507 EN A. Johari Department of Civil and Environmental Engineering, Shiraz University of Technology, Shiraz, Iran 0000-0002-5988-6964 A. H. Amjadi Department of Civil and Environmental Engineering, Shiraz University of Technology, Shiraz, Iran A. Heidari Department of Civil and Environmental Engineering, Shiraz University of Technology, Shiraz, Iran Journal Article 2020 05 19 This study attempts to investigate the influence of the dynamic soil properties uncertainties on ground response analysis via a case study site. For this purpose, nonlinear time-domain ground response analysis and uncertainties in soil parameters are coupled simultaneously using a coded program in MATLAB. To take full advantage of the real data, two investigation boreholes are drilled in the site. The analysis is performed deterministically and then extended to the stochastic context in order to take into consideration the variability of Plastic Index, shear wave velocity, and unit weight of the soil. In a part of this study, the capability of the three different methods for predicting the stochastic fundamental period of the site including modal analysis, approximate method, and nonlinear method, is investigated. To achieve the advantage of the stochastic analysis, the maximum Coefficient of Variation (COV) of the peak ground motion parameters, fundamental period, response spectrum, and amplification factor are calculated. The results demonstrate that the heterogeneity of the soil parameters has a significant effect on the variation of the surface Peak Ground Displacement (PGD). Among the other stochastic responses, the fundamental period has received the least effect from soil parameters’ uncertainty. https://scientiairanica.sharif.edu/article_22130_d72250f6161cc82e0327ee56b2c3d974.pdf