Yield strength of masonry-like structures containing thin adhesive joints: 3D or 2D-interface model for the joints?

It is shown in this Note that the use of a 2D-interface model for the joints in the limit analysis of a structure made of bricks which are bounded with adhesively thin joints leads to an upper bound estimate of the bearing capacities of the structure, as the thickness of the joints goes to zero. Considering the compression in the vertical direction of a running bond masonry made of Drucker-Prager bricks and mortar, it is found that the use of the interface model overestimates by 15 percent the compressive strength of the masonry computed with 3D finite elements. Moreover, comparisons with compression test results show that the damaging behavior of the bricks has an important effect on the actual compressive strength of the masonry. (C) 2011 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.