矿物掺合料对机制砂水泥基自流平砂浆性能的影响

Influence of Mineral Admixtures on the Properties of Machine-made Sand Cement-based Self-leveling Mortar

试验选用普通硅酸盐水泥、硫铝酸盐水泥与半水石膏的三元胶凝体系,选用机制砂作为细集料,制备全机制砂水泥基自流平砂浆。选用粉煤灰、石粉与硅灰作为矿物掺合料,并研究矿物掺合料对全机制砂制水泥基自流平砂浆流动度、抗压抗折强度与尺寸变化率的影响。研究结果表明:矿物掺合料的火山灰效应对自流平砂浆力学性能的发展产生积极影响,自流平砂浆流动度随硅灰掺量的增加而减小。通过正交试验优化自流平砂浆配方,得到最优矿物掺合料掺量为粉煤灰7%、石灰石粉4%、硅灰1.0%。

The test uses a ternary cementing system of ordinary Portland cement,sulphoaluminate cement and hemihydrate gypsum,and chooses machine-made sand as fine aggregate to prepare fully machine-made sand cement-based self-leveling mortar;chooses fly ash,stone powder and silica Ash as a mineral admixture to study the influence of mineral admixtures on the fluidity,compressive and flexural strength and dimensional change rate of cement-based self-leveling mortar made of fully machine-made sand.The pozzolanic effect of mineral admixtures has a positive impact on the development of the mechanical properties of self-leveling mortar,and the fluidity of self-leveling mortar decreases with the increase of silica fume content.The formula of self-leveling mortar is optimized through orthogonal experiments,and the best content of the excellent mineral admixture:fly ash 7%,limestone powder 4%,silica fume 1.0%.