Evaluation of the Influence of Floor Plan Geometry of Reinforced Concrete Buildings on the Soil-Structure Interaction Mechanism

Resumo

This study aims to evaluate the effect of floor plan geometry of reinforced concrete buildings on the soil-structure interaction (SSI) mechanism. Two three-dimensional finite element models were developed using the SAP2000 software: (i) a model with a square floor plan and (ii) a model with a rectangular floor plan. Both fixed (rigid) supports and elastic (spring) supports were employed in the analyses to simulate foundation behavior. The results indicate that both models exhibit similar SSI responses, with noticeable redistribution of internal forces when interaction is considered. Peripheral columns experienced increased axial demands, while central columns showed a reduction. Additionally, there was an increase in positive bending moments at mid-spans and negative moments at the peripheral supports of the central ground floor beam. These findings highlight that neglecting settlement effects - by disregarding SSI in the design process - can result in bending moment diagrams that deviate from design assumptions, potentially leading to localized plastic hinges in beams. It is also noteworthy that the rectangular floor plan exhibited higher differential settlement values, making the influence of SSI even more significant in the structural and foundation design.