关键词: 烧结烟气脱硫灰, 粉煤灰, 铁尾矿, 矿相调整, 化学激发, 水化硅酸钙（C—S—H）

Abstract: To improve the utilization rate of solid wastes produced in metallurgy industry,a solid waste based cementitious material was prepared by mixing the steel slag powder with sintering flue gas desulfurization ash.Fly ash was used to adjust the Si/Al minerals composition of solid waste based cementitious material,and triisopropanolamine (TIPA) was used to activate its hydration activity.Firstly,the mechanical properties,hydrates assemble,hydration product morphology,pore structure and hydration heat release were investigated,so the effect of fly ash and TIPA on the hydration progress of steel slagdesulfurized ash based cementitious materials were studied.Secondly,the mechanical properties and interface transition zone (ITZ) characteristic of mortars prepared by steel slagdesulfurized ash based cementitious materials and iron tailings sand were investigated.Conclusion were made as follow:Single blending of 20% fly ash obviously promoted the formation of C—S—H and increased the 14 day compressive strength of paste by 1.86 times,but the 3 and 7 day compressive strength decreased when the fly ash content increased to 50%.Using TIPA alone increased the 3 day compressive strength from 0.52 MPa to 11.44 MPa,and its complexation to iron ions also promoted the hydration of steel slagdesulfurized ash based cementitious materials with high fly ash content (50%),which obtained a 3.69 MPa compressive strength at 3 day.The Ca(OH)2 grew among the C—S—H but did not directly contact the aggregates.Ettringite grown vertically on the surface of the aggregates were observed when fly ash was added for minerals phase adjustment.