Allowable Torsional Eccentricity for the Simplified Method for the Seismic Analysis of Low-Rise Confined Masonry Shear-Wall Buildings of Mexican Codes

Abstract

A parametric study devoted to assess the limiting value for the static eccentricity (es) for the application of the simplified method for seismic analysis (SMSA) of bearing-wall confined masonry structures of Mexican Building Codes is presented. Based upon the results of a comprehensive parametric study, limiting values for es for the use of the SMSA are proposed for three different performance levels for the structure: (a) elastic response, (b) completely nonlinear (cracked) response of all walls along the building height and, (c) partially nonlinear (cracked) response along the height. The criterion used to propose limiting values for es was that the underestimation of shear forces predicted for the first story walls with the SMSA was within reasonable limits with respect to those shear forces computed with a rigorous 3D static analysis using an equivalent linearization for the nonlinear (cracked) response of the walls, in order to insure reasonably safe designs of such structures.