Experimental characterization of AAC masonry in shear: Effect of block density, mortar, and test setup

The paper discusses the results of an experimental program devoted to the characterization of AAC masonry in shear, by studying the effect of different key parameters: test setup, block density, and mortar type. As for ordinary masonry assemblages, shear parameters of AAC masonry can be determined from either shear tests on triplets or diagonal compression tests. However, the extension of these methodologies to AAC blocks with low densities is not so straightforward and highlights some critical issues. To evaluate the influence of block density (and block strength) on the shear parameters and on the observed modes of failure, masonry triplet and diagonal compression tests were performed for AAC blocks characterized by two different densities (300 and 480 kg/m3). Moreover, for the higher density class, tests were repeated by also varying the mortar type. Although most of Standard codes mainly relates the shear resistance of thin-layer masonry to the block material, the obtained results highlight that also the mortar type and the surface treatment before mortar application may have a not negligible influence on the final behavior.