Out-of-plane shaking table tests on URM single leaf and cavity walls in two-way bending

Abstract

Damage observations from recent seismic events have confirmed that the activation of out-of-plane (OOP) local mechanisms is one of the major causes of structural collapse in unreinforced masonry (URM) buildings. Such failures are mostly due to the attainment of displacement levels incompatible with equilibrium configurations for the kinematic chain of the considered mechanism rather than the exceedance of stress capacity in structural elements. However, very little research can be found currently in literature regarding the two-way bending OOP failure mechanism of walls involving at least one restrained vertical edge despite it being one of the most commonly reported and surveyed cause of structural damage. The paper takes a step towards addressing this lack of knowledge in the form of dynamic testing of full-scale URM masonry walls. In particular, results of three of these tests are reported in this paper: a test on a specimen representing the calcium silicate inner/loadbearing wall, a test representing the clay outer wall, and a cavity wall composed of both leaves together.