Rigid, Semi Rigid, and Flexible Diaphragms for Horizontally Asymmetric Building

Abstract

The development of architectural design has increased numerous types of irregularities in structures, one of them is a T-shape building. The asymmetrical plan structure can induce a more unstable response due to earthquake loads. Buildings are generally designed using a rigid diaphragm rather than a semi rigid and flexible diaphragm. This study aimed to analyze the effects of diaphragm flexibility on structural response such as natural period, deformation, and base shear forces. The gravity and seismic loads on the buildings were based on SNI 1727:2013 and SNI 1726:2019. The finite element software program was used for modeling and running the analysis of structure. The results reveal that the rigid diaphragm structure has higher stiffness and generates smaller story displacement and base shear force than semi rigid and flexible diaphragm structures. The flexibility on irregular structure also affects the structural mode shape significantly.