Shear-Compression Test on Masonry Walls with an Innovative Experimental Setup

The behavior and failure mechanism of a masonry wall subject to in-plane shear depends on several factors, such as the wall geometry, the boundary conditions, the acting stresses, and the masonry mechanical parameters. The objective of this research was the study of the in-plane shear behavior of full-scale masonry panels through an innovative experimental setup, purposely designed to reproduce a double fixed boundary condition in order to induce a diagonal cracking failure mode. Such a boundary condition was ensured by the presence of an upper horizontal rigid steel beam, combined with the possibility of modulating the compressive load applied to the masonry panel, while increasing the horizontal displacement. Nonlinear numerical simulations were carried out to analyze the capability of the experimental setup of reproducing the desired loading and restraint conditions and to predict the shear behavior of a clay brick masonry panel. A finite element model was realized, in which all the components of the experimental setup were included to account for all possible failure modes, and the masonry panel was modelled according to a macro-modelling approach. The results of the numerical predictions were compared with the results of a shear-compression test on a masonry panel, which will be presented in the paper. The good agreement obtained between the numerical and the experimental results, both in terms of load vs displacement curve and development of the cracking process, confirmed the suitability of the setup in reproducing the assumed boundary conditions and shear failure mode.