Structural Analyses of Rc Buildings With Various Support Types

Abstract

The seismic design of buildings is performed based on dynamic analyses by considering fixed-base supports. The effect of soil’s elastic behavior is usually ignored during the analysis and design phases of buildings. Due to differences in the seismic responses of rigidly and elastically supported buildings, it is essential to study the impact of the elastic behavior of soil on overall building design. In this study, the structural behavior of rigid basement walls with various support conditions will be investigated. For this purpose, a parametric study will be conducted on a total of 60 reinforced concrete buildings with two different layouts. For this purpose, five support types will be studied. These supports types in their correct order are as follows: (1) vertical area springs at the base coupled with horizontal area springs all around the basement walls, (2) fixity at the base coupled with horizontal joint springs only at the ground floor level, (3) vertical joint springs at the base, (4) only fixity at the base with no joint or area springs, and (5) vertical joint springs at the base coupled with horizontal joint springs only at the ground floor level. The results revealed that the buildings with support type 2 exhibited the most rigid behavior, while the buildings with support types 1 and 3 exhibited the most flexible behavior. The fundamental periods from support type 5 were always smaller than those from support type 1, pronouncing the significance of the presence of horizontal springs. Based on the results, it was also concluded that the choice of support type had almost no impact on the design of a mat foundation. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.