M. S. Karimi - Ph.D., Dept. of Civil Eng., Semnan University

In this paper examples of Discrete Element analyses of unreinforced single leaf clay brick/concrete block masonry shear walls with or without opening, under a non-proportional confined vertical and monotonic lateral loadings are presented. In this semi-detailed Discrete Element modelling, units (bricks/blocks) are modelled as conventional continuum elements, while an interface contact law (instead of mortar joints) is used to capture masonry failure mechanisms in the 2D plane-strain analyses. A multi-surface plasticity algorithm of the contact law includes softening for tension, shear and compression modes. A general layout of the physically tested models has been given together with the comparison of the DEM results with the experimental ones and other numerical modellings (in the literatures), to assess validation of the used contact law model. Under the plasticity model for the unit material, DEM was greatly able to trace entire response of the masonry shear walls in their path loads (up to and beyond the peak load until total degradation of strength), crack pattern and deformation, and also the failure process, all in a good and reasonable estimate of the experimental results. It is also able to get a limit load by DEM even in lack of any non-linearity for the unit material. The increase of vertical resultant force in the supports demonstrates the dilatant behaviour is also reproduced well by this method.

Masonry wall, Shear Load, Discrete Element Method