In-plane cyclic tests of unexplored URM walls: “Doppio UNI” and “header bond” clay brick typologies

This paper presents the results of two experimental tests performed at the EUCENTRE Foundation (Pavia, Italy). The aim of these tests was to assess the in-plane behaviour of two distinct unreinforced masonry typologies commonly encountered in the existing building stock, which have not been previously investigated through experimental research. The first typology consisted of solid clay bricks and lime mortar arranged in a “header bond” pattern, while the second involved typical Italian hollow clay “doppio UNI” units and cement-lime mortar arranged in a “Flemish bond” pattern. To thoroughly examine these masonry typologies, a comprehensive characterization was conducted. Following the characterization, two full-scale specimens, one for each masonry typology, were subjected to cyclic in-plane pseudo-static tests to investigate the shear response of the walls. Various seismic performance parameters, such as energy dissipation, elastic and secant stiffness, lateral strength and displacement capacity, were evaluated and compared with the provisions outlined in the current European seismic codes.