Dynamic Modeling of Soil-Structure Interaction for Seismic Performance Evaluation of Reinforced Concrete Building

This study focuses on the effect of soil-structure interaction on the dynamic behavior of structures subjected to seismic movements. A 2D model of a simple minaret, 18.4 meters tall with a width and length of 3.5 meters, was analyzed using the SAP2000 V21 finite element software. Two types of seismic loading were applied: the response spectrum of Algerian seismic regulations (RPA 99 version 2003) for low seismicity (zone: Z1), and accelerograms measured at the Keddara site in Boumerdès, Algeria, in 2003. The soil foundation is classified as type S3 (loose soil), and the analysis included conditions both with and without soil-structure interaction. The results indicate significant impacts of soil-structure interaction: the inclusion of soil effects led to a 25% reduction in base shear and a 15% increase in the fundamental period of the structure compared to the reference model without soil interaction. Additionally, nodal horizontal displacements at the top of the building increased by 40% when accounting for soil-structure interaction, affecting the overall stability and design considerations. This study underscores the importance of incorporating soil-structure interaction in the design process, as neglecting these effects could lead to underestimating the seismic demand and potentially compromise structural integrity.