Effect of matrix components with low thermal conductivity and density on performances of cement-EPS/VM insulation mortar

Abstract

Cement-EPS/vitrified (CEV) microsphere (VM) insulation mortar was prepared by using sulphoaluminate cement as cementitious material, and EPS and VM as insulation aggregates. The performance of matrix with insulation aggregates could not only determine the mechanical property of CEV mortar, but also affect its thermal conductivity. In this paper, the effects of matrix components, such as SCM, including fly ash (FA), superfine slag (SS) and paper sludge ash, with low thermal conductivity, OPC with low cost, polypropylene (PP) fiber with low density, on the mechanical property and dry density of CEV mortar were investigated. Under satisfying the standard requirement of CEV mortar, 8–20 % of FA and 3–5 % of SS can decrease effectively its thermal conductivity and density. Similarly, the addition of 10–30 % of paper sludge ash has similar effects of CEV mortar. Twenty percent of OPC will decrease significantly the cost of CEV mortar. 0.2 % of PP fiber can improve obviously the flexural strength and decrease its dry density of CEV mortar.