Splitting Test on Masonry Cores and modeling of the Confined mortar behavior based on fracture energy

Document Type : Research Article


Department of Civil Engineering, Engineering Faculty, Razi University, Kermanshah, Iran.


The in situ evaluation of the masonry's mechanical properties is a very complicated task. A viable alternative is based on the use of brick cores including a central mortar layer lying on a symmetry plane. In fact, these specimens can be extracted very easily by cutting cores spanning two bricks at least. The obtained core is then subjected to a splitting test with a setup providing a different inclination of the mortar layer with respect to the loading plane. This type of test is similar to a diagonal wallet test and induces a mixed compression–shear stress state in the central mortar layer. Here, This test is used for masonry with sand and cement mortar. By using a Mohr-Coulomb failure criterion the test result can be interpreted in order to obtain all the mechanical properties of the masonry. This test can be a good alternative to other semi-destructive tests, especially the shove test. The latter test has a defect, that’s due to the lack of effect of dilatancy in the shear behavior of mortar in the shove test, the values ​​obtained in terms of cohesion and friction angle will be greater than the actual value. In the following, a 3D continuous micromodel is presented in order to predict unreinforced masonry behavior. Due to the difference in the modulus of elasticity, the Poisson ratio and the thickness of the brick and mortar, several efforts have been made to simulate the compressive behavior of the masonry using different models with different goals and results. To examine this behavior, which is influenced by the interaction of units and mortar, in one hand, two-dimensional models are not able to consider the 3D confined effect. On the other hand, the three-dimensional models are not able easily to control the effect of 3D confined and dilatation explicitly. The proposed model is based on the concept of micro-plane and is developed to model failure in masonry structures.


Main Subjects

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