Masonry shear walls are the main structural elements that resist in-plane lateral loads applied to a masonry building. The current Canadian Code assumes the shear resistance of a masonry wall to be the sum of two components: the shear resistance of the masonry and the shear resistance of horizontal reinforcement. This assumption is a point of debate with respect to other codes and design expressions. The results of estimating the shear resistance with the Canadian Code design formula are very conservative as they significantly underestimate the shear resistance of walls.
In the current study, the behaviour of sixty six concrete masonry walls with the same aspect ratio but with different methods of reinforcement, axial stress, methods of construction and grouting was investigated. The aim of the study was to understand the shear behaviour of concrete masonry walls better and to investigate the influence of changing each variable on the shear strength of the walls. In this study, the results were analyzed using different statistical methods to identify the significance of the variation between the results obtained.
Finally, based on the results, a new formula for predicting the shear strength of concrete masonry walls with aspect ratios less than 2 is proposed. The formula was examined against test results reported in literature and the results of the tests described in the thesis.
The formula proved on average to estimate the shear resistance of all the walls better than other code and design expressions and with less variability.