Simplified Formulation for Modeling the Nonlinear Behavior of Confined Masonry Walls in Seismic Analysis: Fid-Bau Portal

Simplified Formulation for Modeling the Nonlinear Behavior of Confined Masonry Walls in Seismic Analysis

Ranjbaran, Fariman / Hosseini, Mahmood / Soltani, Masoud

Past earthquakes have shown the vulnerability of masonry of buildings in several cases; however, experimental results represent ductile behavior of structural elements of such buildings, specifically confined masonry walls. Design of buildings of this type is usually performed in a prescriptive manner without numerical modeling and performed out of the framework of an analysis-designing process. The purpose of this research is to identify the major factors affecting the behavior of the confined walls against lateral and vertical forces and to then present a simplified behavioral model precise, as much as possible, and simple enough to be used by professional engineers. The proposed model can show the wall behavior before and after cracking. A series of nonlinear static analyses in parametric form has been performed using a wide range of effective factors on confined masonry walls with or without opening. Then, based on the numerical results, some simple formulas have been proposed to express the relationships between the lateral strength of the confined wall and the wall specifications, including the initial stiffness, the secondary stiffness after cracking, the ultimate strength, and ductility, to be used in engineering programs such as SAP, which are widely implemented in engineering firms, by practicing engineers.