Testing masonry blockwork panels for orthotropic shear strength

In this paper the problem of evaluation of the structural response of 1.20 m × 1.20 m blockwork masonry panels under monotonic shear and diagonal-compression tests is investigated. The digital image correlation technique was used to detect the initiation and propagation of damage. The experimental findings were analyzed and simulated also by means of accurate finite element non-linear analyses. The results revealed the non-isotropic shear response of the masonry panels, which is related to the meso-scale structure. The shear response along the two principal directions, when investigated by a test configuration which recall the Iosipescu method, proved to be quite different, being the shear strength parallel to the bed joints mainly dependent on the mortar properties, while the shear strength perpendicular to the bed joints is affected by the bond pattern. The standard diagonal compression tests, on the other hand, showed an intermediate response, even if the orthotropy of shear response could not be explicitly manifest.