多组分工业废渣水泥砂浆的热稳定性及力学性能研究

Thermal stability and mechanical properties of multicomponent industrial slag cement mortar

采用测长法进行热膨胀性能试验,评价胶凝体系及不同组分工业废渣水泥砂浆的热稳定性,通过热稳定性、高温力学性能试验优选砂浆配合比,并分析其耐热机理。结果表明:矿物掺合料有利于改善胶凝体系的热稳定性,其中粉煤灰掺入效果相对明显;废渣集料对砂浆热稳定性的影响主要与集料自身的热膨胀性能有关,钢渣砂的热膨胀系数小于天然砂,对其具有可替代性;矿物掺合料与集料的合理搭配能够优化砂浆的高温力学性能;粉煤灰复掺玄武岩水泥砂浆试件的耐热性能较好,其线膨胀系数稳定,室温~450℃的平均线膨胀系数为7.93×10^(-6)/℃,450℃高温后抗压强度达到60.4 MPa。

The thermal expansion performance test was carried out using the length measurement method to evaluate the thermal stability of the cementitious system and industrial waste slag cement mortar with different components.The thermal stability and high temperature mechanical properties tests were used to optimize the mortar mix ratio and analyze its heat resistance mechanism.The results show that the mineral admixture is beneficial to improve the thermal stability of the gelation system,and the effect of fly ash incorporation is relatively obvious;the effect of waste slag aggregate on the thermal stability of the mortar is mainly related to the thermal expansion performance of the aggregate itself.The coefficient of thermal expansion of steel slag sand is less than that of natural sand,which indicates that natural sand is replaceable by steel slag sand;the reasonable combination of mineral admixtures and aggregates can optimize the high-temperature mechanical properties of the mortar;the heat resistance performance of the fly ash mixed basalt cement mortar specimens is superior,whose linear expansion coefficient is stable,and the average linear expansion coefficient in the temperature range from room temperature to 450℃is 7.93×10^(-6)/℃,and the compressive strength after 450℃reaches 60.4 MPa.