Study on improving properties of desulfurized gypsum based cementitious materials

Abstract

Two kinds of inorganic reinforcing materials, single Portland cement clinker, compound Portland cement clinker and mineral powder, were used to analyze the effects of desulfurized gypsum on the properties of desulfurized gypsum based cementation material. The results show that either single Portland cement clinker or compound Portland cement clinker and mineral powder can effectively improve the mechanical properties and softening coefficient of the material, and the effect of compound mixing is better. The optimum dosage of Portland cement clinker is 10%, the 7d and 28d bending strength of cementing material is 2.5MPa and 4.1MPa, the compressive strength is 4.6MPa and 9.8MPa, and the softening coefficient is 0.61. The appropriate composite content of Portland cement clinker and mineral powder is: Portland cement clinker 5%~10%, mineral powder 10%~15%, gelling material 7d, 28d bending strength of 3.0~3.5MPa, 6.3~7.4MPa, compressive strength of 5.4~6.7MPa, 12.1~13.6MPa, softening coefficient of 0.58~0.62.