Design and Construction of Hybrid Concrete-Masonry Structures Informed by Cyclic Tests

Abstract

Reinforced concrete buildings with masonry infill are vulnerable in earthquakes primarily because the masonry walls often fail due to out-of-plane forces and can trigger soft-story collapses. In order to prevent these failures, many engineers in the Caribbean have partially reinforced the infill walls and connected them to the reinforced concrete frame. This forms a hybrid concrete-masonry structure. Hybrid concrete-masonry structures have the potential to improve the seismic performance of many structures across the globe, as they are an easy adaptation from traditional unreinforced masonry infill. However, there is little codified guidance for this type of structure, and the influence of the masonry infill and dowel connections on the in-plane behavior of the frame is often neglected. This paper summarizes the current design and construction practices for hybrid concrete-masonry structures and assesses their seismic performance via cyclic tests on full scale test specimens. Based on the results of the experiment, a method is proposed to account for the dowel connections and the partially reinforced infill when designing hybrid concrete-masonry structures in earthquake zones.