Beneficial Effects of Infill Walls on the Structure and Foundation Lateral Performance Under the Effect of Seismic Loads

Abstract

Reinforced concrete structures with infill walls are the most common in practice and construction in seismic zones around the globe, these structures are vulnerable to additional loads from earthquakes that may cause structure failure and collapse. The infill walls are considered as nonstructural components in the design process, the influence of its mass is considered, while neglecting its mechanical properties such as stiffness and strength leads to negative significances. Therefore, this study aims to investigate the effect of infill walls on the performance of structure, foundation, and confined soil during earthquakes. For this purpose, a full-scale model with and without walls was investigated under the effect of seismic loads. The numerical analysis program PLAXIS 3D was conducted in this current study. A residential building consisting of nine stories and a basement with a raft foundation resting over dense sand soil was modeled as a three-dimension model with and without infill walls. Results confirmed that walls improved the structure stability and increased the structure and foundation resistance to horizontal displacement. Results showed that the maximum reduction in the structure displacement and acceleration with walls was 71% and 50% respectively compared to the bare structure. Also, the infill walls reduced the foundation's horizontal displacement and vertical settlement by 38%. Finally, wall presence has a vital role in the adjustment and modification of the soil's dynamic properties. So, considering the contribution of infill walls behavior is very important as a novel technique to improve the structure resistance and dissipate seismic energy.