Modified supersulfated cements

Abstract

The paper presents the results of experimental studies of the possibility of obtaining modified supersulfate cements (SSC) with improved physical and mechanical properties on lowalumina blast-furnace granular slags. It has been shown in comparative experimental tests of the effect of admixtures of various sulfate activators that the highest strength of cements is achieved when using a phosphogypsum neutralized with lime. An additional activating effect has been established for supersulfated cements with the introduction of admixtures fluorides and, in particular, fluorides of magnesium, calcium and sodium silicofluoride. The additional introduction of hardening accelerators and their compositions with a superplasticizer into the SSC composition makes it possible to increase the compressive strength of cements at 28 days of age up to 60-65 MPa while achieving high strength at an early age. Along with standard tests, experiments were performed using mathematical planning with obtaining adequate regression equations.