9523023 Colville The objective of the research is to investigate the enhancement of the flexural tensile bond strength of masonry mortars by the use of latex additives in the mortar mix. The research builds on a previous project which identified several areas of potentially significant research. These include the effect of polymer content, effect of lime, curing procedure and flow, type of plasticizer, and moisture content of masonry. This research will provide approximately 1000 test values on brick masonry prisms constructed with a variety of latex additives that have already been proven to have considerable potential on increasing the tensile bond strength of clay masonry construction. The study will be directed into three phases. Phase 1 will evaluate 9 polymer types in detail (588 tests). Phases 2 and 3 (336 tests) will focus on those 16 contributions from the 36 mortar batches tested in Phase 1 that are shown to provide the greatest enhancement in flexural bond strength. The research will provide for the first time, a comprehensive data base on the enhancement of the flexural bond strength of polymer modified mortars. This is in itself significant since there is no current data available that indicates whether or not the traditional weal link masonry (i.e., the bond between mortar and masonry unit) can be significantly improved through the use of such additives. The recent enhancements in concrete strength and durability through the use of various additives and superplasticizers in the concrete mix, cannot be applied directly to masonry mortars. The potential impact of such bond strength enhancement on the use of unreinforced masonry construction has important implications both in retrofitting and strengthening existing masonry construction and in the design of new construction. ***
