Reinforced masonry shear walls with boundary elements (RMSW+BEs) have emerged as a reliable seismic force-resisting system (SFRS) under the Canadian Standards for the Design of Masonry Structures (CSA S304-14) and the National Building Code of Canada for 2015 (NBCC 2015). While reinforced concrete (RC) core walls are commonly used as an SFRS in RC structures due to their ability to allocate staircases and elevators conveniently. The reinforced masonry core walls with boundary elements (RMCW+BEs) remain underexplored in seismic performance studies. The conservative shear strength calculations in CSA S304-14 limit the height of RM ductile shear walls as specified by NBCC, highlighting the need for further research into RM shear strength with varying design parameters.
This research is divided into two phases. Phase I, titled "Seismic Performance Evaluation of the System-level Response of RMCW+BEs," introduces the Applied Element Method (AEM) as a modeling technique to capture the cyclic behavior of fully grouted RM shear walls and the dynamic response of RM buildings. A new structural layout for RM buildings is proposed, with RMCW+BEs as the primary SFRS. The phase evaluates the seismic response of RMCW+BEs designed per CSA S304-14 provisions and examines the effect of higher modes of vibration on seismic performance of RM structures. The ductility and overstrength of the proposed system are quantified using nonlinear pushover analysis following FEMA P695 guidelines, and incremental dynamic analysis (IDA) is used to assess seismic collapse risk and to develop system-level-based fragility curves.
Phase II, titled "Experimental Investigation of the Component-Level Response of RMCW+BEs," includes diagonal tension tests on 41 masonry assemblages to evaluate the impact of different vertical and horizontal reinforcement ratios on RM shear strength. A quasi-static cyclic test on a C-shaped RMCW+BEs was conducted to simulate the first story response of a 12-story prototype building’s core wall.
The research demonstrates enhanced performance of RMCW+BEs under design-level earthquakes, meeting the ductility, overstrength, and deformation capacity requirements for a ductile SFRS. The findings support the adoption of RMCW+BEs as an effective SFRS in future North American masonry design standards.