大掺量矿渣-水泥复合胶凝材料体系的性能研究

Properties of cement pastes containing high volume granulated blast furnace slag(GBFS)

研究了不同细度矿渣对水泥基复合胶凝材料性能的影响,分析了复合胶凝材料体系的力学性能,并采用扫描电子显微镜(SEM)、压汞法(MIP)、热分析(TG-DTG)测试了矿渣-水泥复合胶凝材料体系的微观结构及水化产物,结果显示:矿渣的掺量对复合胶凝材料体系性能具有较大影响,具体表现为50%~70%矿渣掺量范围内,随掺量的增大,硬化浆体孔渗流程度增大,力学性能降低,且该趋势与细度无关;矿渣细度降低,可细化硬化浆体孔结构,降低孔的渗流程度,水化产物显著增多,微观结构更加密实,从而对力学性能起到正效应。

The effect of slag fineness on the properties of cement-based composite cementitious materials was investigated.The mechanical properties of the composite cementitious material system were analyzed.The microstructure and hydration products were analyzed by scanning electron microscope(SEM),mercury intrusion porosimetry(MIP)and thermal analysis(TG-DTG).The results showed that the slag dosage significantly influences the properties of the cementitious materials.The seepage degree of pores increases with the increment of slag dosage in the range of 50%~70%,regardless of slag fineness.The pore structure of hardened pastes was refined when the fineness of slag decreases.Meanwhile,the seepage degree of pores reduces due to more hydration products,which generates more compact microstructure and benefits the mechanical properties of cementitious materials.