摘   要：选择三个级配区域的铁尾矿砂单独或者组合替代天然砂制备石膏基自流平砂浆，研究其工作性能和力学性能，并与天然砂制备的石膏基自流平砂浆的工作性能和力学性能进行对比，分析铁尾矿砂颗粒形貌及颗粒级配对石膏基自流平砂浆的影响机理。结果表明，用0.3～0.5 mm、0.1～0.3 mm、0～0.1 mm三个颗粒级配区域铁尾矿砂组合全部替代天然砂制备的石膏基自流平砂浆虽然会提高15%用水量，但其工作性能和力学性仍能满足JC/T 1023—2007《石膏基自流平砂浆》对工作性能和力学性能的要求。铁尾矿砂和天然砂的颗粒形貌差异较大导致了石膏基自流平砂浆流动性降低，调整铁尾矿砂及整个石膏基自流平砂浆颗粒级配组合可以提高石膏基自流平砂浆的强度。

Abstract: Three gradations of iron ore tailings are selected to prepare gypsum-based self-leveling mortar for replacing natural sand alone or in combination. The working performance and mechanical performance of the gypsum-based self-leveling mortar are studied. The mechanisms of particle shape and particle gradation of iron ore tailings on gypsum-based self-leveling mortar are analyzed. The results show that the water requirements of gypsum-based self-leveling mortar prepared by 0.3～0.5 mm, 0.1～0.3 mm and 0～0.1 mm iron ore tailings in combination instead of all natural sand is 15% higher than prepared by natural sand. The working performance and mechanical performance of the surface mortar for gypsum-based self-leveling mortar prepared by 0.3～0.5 mm, 0.1～0.3 mm and 0～0.1 mm iron ore tailings in combination instead of all natural sand can meet requirements of standard JC/T 1023—2007 Gypsum hased self-leveling floor compound. The difference of particle shape between iron ore tailings sand and natural sand leads to the decrease of fluidity of gypsum-based self-leveling mortar prepared by iron ore tailings. The flexural strength and compressive strength of gypsum-based self-leveling mortar can be improved by adjusting the particle gradation of iron ore tailings sand and gypsum-based self-leveling mortar.