Seismic performance of shear-critical prefabricated reinforced masonry shear walls with innovative vertical joint connections

Abstract

The in-plane seismic behavior was investigated for five single-story reinforced masonry shear walls (RMSWs) (four prefabricated and one cast-in-place) subjected to an axial compressive load and reverse lateral excitation. An innovative vertical joint connection method for the prefabricated RMSWs was developed. The variables under study were the level of axial compressive stress, horizontal reinforcement ratio, and construction method. The experimental results showed that all walls had a similar failure mode with diagonal cracking. However, the crack distribution depended strongly on the construction method. The bearing capacity of the walls increased with the applied axial compressive stress and amount of horizontal reinforcement. The prefabricated walls showed better post-cracking performance than the cast-in-place wall. The wall secant stiffness decreased rapidly to approximately 60% of the initial stiffness when the first major diagonal crack occurred. The idealized equivalent elastic–plastic system indicated that the prefabricated RMSWs had greater displacement ductility of 2.6–4.7 than the cast-in-place RMSW. The equivalent viscous damping for the walls was 0.10–0.20 at 0.32% drift, which indicates that RMSW buildings can be expected to provide a high level of damping to reduce the seismic demand.