THE EFFECTS OF BRICK AND MORTAR WATER CONTENT DURING CONSTRUCTION ON THE SEISMIC STRENGTH OF BRICK WALLS

An important factor affecting the strength of a masonry wall is the capacity of the bond between the mortar and the bricks to transfer the loads within the wall. The main parameter affecting the bond strength is the water content of the bricks and mortar during the construction and post-construction moisture curing of the wall. Using dry bricks and mortars invariably results in weak bonds and therefore a weak wall. In this paper, the results of a number of tests conducted on typical Iranian wall construction will be presented. The walls are constructed using the traditionally made, solid bricks and the fine aggregate used for making mortar. Four walls are tested in total. Two walls are tested for the out-of-plane bending strength investigations and the other two for the in-plane shear capacity. Of each pair of walls, one is made using the usual dry bricks and mortar mixes and no post-construction curing and the other is made using the bricks in a surface dry state, a standard mortar consistency and moisture curing the wall for 28 days. The walls are tested using step-by-step pushover loading of the walls to destruction. The strength and seismic performance parameters of the walls are then extracted from the pushover test results and compared to drive at a quantitative conclusion at the effects of the material water content and method of curing on the seismic strength of typical Iranian wall construction.