Structural Reliability of Non-Slender Loadbearing Concrete Masonry Members under Concentric and Eccentric Loads

Abstract

Although the reliability levels of structural steel and reinforced concrete structures designed to the Canadian codes and standards have been investigated substantially in the past four decades, studies on the reliability of masonry structures are limited. Based on some preliminary studies in 1980s, the design of masonry structures using the limit states method was introduced in the 1994 edition of the Canadian standard S304 in order to provide more uniform and economical design guidelines. However, the limit states design criteria were not supported by a rigorous reliability-based analysis. The investigation reported herein was carried out to contribute to filling the gap in our knowledge on the reliability of structural masonry members designed using the limit states method, to establish reliability levels for masonry comparable to other structural materials and to help remove any unnecessary conservatism in the masonry design process. The first order reliability method was used to assess the reliability of unreinforced and reinforced non-slender concrete masonry walls under combined axial load and out-of-plane bending. In this research, only non-slender walls having a slender ratio (kh/t) not requiring consideration of second order effects are considered. Nevertheless, the procedure for performing the reliability analysis for walls with larger kh/t is proposed and explained.