Experimental analysis of timber inclusions effect on paraseismic behavior of earth masonry walls

Abstract : This research aims at the seismic assessment and understanding of a traditional loadbearing system incorporating horizontal timber elements into earth brick masonry walls. In order to characterize the global behavior of the loadbearing device, an experimental campaign was performed on the constituents (i.e. bricks and mortar) and on masonry samples. Compression tests were carried out on four geometries of earth brick samples and three geometries of earth mortar samples. As the methods to obtain the compressive strength of earth material are still discussed within the scientific community, a focus was made on different configurations tested. Uniaxial compression tests were performed on two earth brick wallets. Then, two brick walls (with and without horizontal timber reinforcement) were submitted to lateral quasi-static cyclic load. A LVDTs system and a stereo correlation image system were coupled to study the experimental response of the reinforced and unreinforced walls. This investigation led to estimate the lateral strength, the stiffness degradation and the dissipated energy of both reinforced and unreinforced masonry walls. Moreover, it allowed the comparison between the failure modes of the two types of wall. This analysis brings light on the mechanical impact of the horizontal reinforcement.