ABSTRACT
Procedures regarding slender masonry wall strength capacity design in the Canadian Standard for Design of Masonry Structures (2014) are overly conservative. In the determination of secondary moment the calculated effective stiffness term, EIeff, is believed to be a significant source of error. The lateral deflections of concrete block walls tested by Hatzinikolas et al. (1978a) are compared to deflections calculated following the Standard to predict the error of EIeff. It is found that EIeff is quite inaccurate at low vertical axial load eccentricities. Using data provided by Hatzinikolas et al. (1978a), the relationship between EIeff and axial load (P/Pcr) is plotted, with some plots suggesting several slender walls with low load eccentricities are failing in compression rather than by buckling. It is proposed that the vertical axial load eccentricity be considered in addition to the slenderness ratio (kh/t) in defining walls for which buckling must be considered in design.
