Research On Using Cfbc Fly Ash And High Titanium Slag To Prepare Ordinary Wet-mixed Mortar

Somewhere in Sichuan province is facing up the serious shortage of natural sand resource and the dispose of a vast amount of industrial waste which is represented by CFBC fly ash and high titanium slag. In this paper, CFBC fly ash and high titanium slag coming from somewhere in Sichuan province were used as the main raw materials to prepare the ordinary wet mixing mortar, that holp to solve the above problems and the feasibility of that based on the following three reasons. First,CFBC fly ash possesses the prominent pozzolanic activity and the high gelling ability if it is motivated by alkali, so CFBC fly ash has the potential to act as the cementitious component of mortar. High titanium slag possesses good chemical stability and the grain composition similar to natural sand, so high titanium slag has the potential to act as aggregate of mortar. Second, technical requirements of the ordinary wet mixing mortar are more appropriate for the mortar system. Third, raw materials have the advantage of using local materials.The ordinary wet mixing mortar which was prepared in this project includes ordinary wet surfeace mortar, ordinary wet masonry mortar and ordinary wet flooring mortar. Influences of fineness of CFBC fly ash, cement-sand ratio and carbide slag content on properties of wet mortar were studied by orthogonal and individual factor experiments, therefore, the fiducial mix proportion of wet mixing mortar could be determined. For improving properties of mortar further, influences of cement concent,the substitution rate of high titanium slag, the type and dosage of water reducing agent, the type and dosage of water-retaining admixture and the type and dosage redispersible powder on properties of wet mixing mortar were also studied, therefore,the optimal mix proportion of wet mixing mortar was determined. Simultaneously, part microcosmic physical properties and durabilities of wet mixing mortar were tested.The results prove that the sequence of three factors effecting properties of wet mixing mortar is cement-sand ratio, carbide slag content and fineness of CFBC fly ash.Cement-sand ratio affects mainly water-retention rate, wet densities and compressive strength of mortar. Carbide slag content affects mainly compressive strength of mortar.Fineness of CFBC fly ash water-retention rate and compressive strength of mortar. The fiducial mix proportion of wet mixing mortar is: CFBC fly ash(gringing for 20minutes): carbide slag: high titanium slag=0.267:0.067:0.666(w.t.%). Under the fiducial mix proportion, there are some flaws in the properties of wet mixing mortar, for example, the development rate of early strength is slow, and bond strength is woefully inadequate and so on. Cement is conducive to improving the early strength of wet mixing mortar. Using river sand can improve wet densities and compressive strength of wet mixing mortar. Water reducing agent has no a significant influence on properties of wet mixing mortar. Water-retaining admixture can enhance water-retention rate and peaceability of wet mixing mortar, but it can also reduce wet density and compressive strength of wet mixing mortar. Redispersible powder can enhance bonding strength, water-retention rate and peaceability of wet mixing mortar, especially the bonding strength, but it can also reduce wet density and compressive strength of wet mixing mortar. Ordinary wet surfeace mortar(M5),ordinary wet masonry mortar(M15,M20,M25) and ordinary wet flooring mortar(M15,M20,M25) were prepared by CFBC fly ash and high titanium slag as main raw metarials which derived from somewhere in Sichuan province, and properties of this mortar satisfy the requirement of Standard JG/T 25181-2010, and the durability of them is well.