LAUSR

Cracking of masonry and plastering mortars of clay brick wall was a major problem in the hot climate area. The problem was the worst for the wall made of lightweight blocks. In this research, masonry and plastering mortars made from Portland cement, fly ash, expanded perlite, mortar plasticizer, and sand were tested. The testing program included the determination of water demand, setting time, water retention, compressive strength, splitting tensile strength, density, and elastic modulus. For the masonry mortar, the mixes with high calcium fly ash with or without plasticizer could be used with required properties and reduced cost. The mix of expanded perlite gave water retention over the required 70%. The mix containing fly ash and 0.2% plasticizer gave water retention slightly less than 70%. It was recommended that the mix with expanded perlite should be used for indoor plastering and the mix with fly ash and plasticizer should be used for outdoor plastering.