热活化煤矸石对水泥基材料性能影响研究

Effect of heat-activated coal gangue on the properties of cement-based materials

将热活化煤矸石用作辅助胶凝材料,替代部分水泥,制备水泥砂浆,研究热活化煤矸石掺量对水泥砂浆抗压强度和抗折强度的影响,及热活化煤矸石增强水泥基材料机械强度的机理。结果表明,在利用热活化煤矸石替代部分水泥制备砂浆过程中,适量热活化煤矸石具有良好的火山灰效应和微集料效应,可促进砂浆基体中相互交联网状C—S—H凝胶的形成,增强砂浆基体中孔隙的填充效果,改善砂浆基体的微观结构,进而提升水泥基材料机械强度。当热活化煤矸石掺入量为20%时,砂浆试样水化28 d的抗压强度可达46.2 MPa,抗折强度达6.79 MPa,其机械强度与纯水泥砂浆相当,完全可以满足一般建筑行业使用要求。

Thermal activated coal gangue as an auxiliary cementing material to replace part of cement to prepare cement mortar,systematically studies the effects of different amounts of thermal activated coal gangue on the compressive strength and flexural strength of cement mortar,and the mechanism of thermal activation of coal gangue to enhance the mechanical strength of cement-based materials was explored.The results show that in the process of using thermally activated coal gangue to replace part of cement to prepare mortar,proper amount of thermally activated coal gangue has good pozzolanic effect and micro aggregate effect,which can promote the formation of cross-linked network C—S—H gel in mortar matrix,enhance the filling effect of pores in mortar matrix,improve the microstructure of mortar matrix,and then achieve the purpose of improving the mechanical strength of cement-based materials.When the amount of thermal activated coal gangue is 20%,the compressive strength and flexural strength of the mortar sample for 28 d after hydration can reach 46.2 MPa and 6.79 MPa,and the mechanical strength is equivalent to that of pure cement mortar,which can fully meet the requirements of the general construction industry.