Numerical modelling of unreinforced masonry walls using contact elements

This paper presents numerical implementation of an interface model for modeling the behavior of mortar joints in masonry walls. Its theoretical framework is fully based on the plasticity theory. The finite element formulation is based on eight node isoparametric element and six node contact element. Von Mises criterion is used to simulate the behavior of the brick unit. The interface laws for contact element are formulated in order to simulate the softening behavior of mortar joints under tensile stress; also a normal linear cap model is used for simulation of crushing of mortar joint in compressive stress. The formulation is verified by comparing numerical results with the results of available test data on shear wall. The numerical prediction base on new tension-compression stress cut off model correlate very well with test data. © Civil-Comp Press, 2010.