Experimental cyclic testing of masonry pier-spandrel substructures reinforced with engineered cementitious composites overlay

This paper experimentally investigated the in-plane seismic behavior of perforated masonry walls (pier-spandrel substructures) retrofitted using engineered cementitious composites (ECC). One unreinforced masonry (URM) specimen and two ECC-reinforced masonry substructures were prepared and subjected to pseudostatic cyclic lateral loads. The failure mode, hysteretic curves, strength, deformability, stiffness, and energy dissipation capacity of three specimens were compared and discussed. The results revealed that the failure pattern of masonry pier-spandrel substructure was improved by the ECC layer with shear failure of masonry piers changing to bending failure. Multiple thin cracks were observed on the surface of ECC overlay. Moreover, the external ECC layer effectively increased the load-carrying capacity and ultimate deformation of the substructures, with maximum increases of 104% in strength and 72% in ultimate displacement, respectively. Finally, the excellent energy dissipation capacity was obtained by ECC overlay, which can improve the collapse resistance of masonry structures subjected to strong earthquake action.