目的目的针对矿山充填材料成本高,工业固废堆积占地等问题,研制了一种含工业固废的新型矿山充填材料。方法方法用氟石膏和粉煤灰代替水泥作为胶凝材料,通过正交实验法探究氟石膏基充填材料的最优配比,并对其力学特性、水化产物、水化作用机理和微观结构进行研究。结果结果结果表明,最优配比材料充填体的1,7,28d强度分别可以达到1.41,4.11,6.47MPa,可满足矿山充填基本要求;膏体坍落度、扩散度、泌水率分别为22.7cm,42.6cm,2.58%,膏体流动性较好,便于运输。氟石膏含量、粉煤灰含量和浆料浓度为材料配比中的3个变量因素,其中对充填体1d强度影响最大的因素为浆料浓度,对充填体7,28d强度和泌水率影响最大的因素为粉煤灰含量,对膏体坍落度和扩散度影响最大的因素为氟石膏含量。充填体的单轴破坏形式为剪切破坏,破坏后内聚力和内摩擦角分别为2.02MPa,32.6°。水化产物包含钙矾石、二水硫酸钙和水化硅酸钙凝胶,水化过程中氟石膏固结体由无水相转化为二水相,其中钙矾石和水化硅酸钙凝胶的增多会形成致密结构,有利于提升充填体抗压强度。结论结论用氟石膏和粉煤灰替代水泥制备的充填材料具备可行性,且成本较低,固废用量占比90%以上,有显著的经济效益,应用前景广阔。

Objectives Aiming to address the high cost of mine filling material and the land occupation issues caused by the accumulation of industrial solid waste, this study developed a new type of mine filling material that included industrial solid waste. Methods The optimum ratio of fluorine gypsum-based filling material was determined through orthogonal experiments. The study examined the material’s mechanical properties, hydra‐tion products, hydration mechanism, and microstructure. Results The results showed that the compressive strengths of the optimal ratio material at 1, 7, and 28 days can reach 1.41, 4.11 and 6.47 MPa, respectively, which met the basic requirements of mine filling. The slump, diffusion and bleeding rate of the paste were 22.7 cm, 42.6 cm and 2.58%, respectively. The paste had good fluidity and was easy to transport. Fluorogypsum content, fly ash content and slurry concentration were the three variable factors in the material ratio. Among them, the factor that had the greatest influence on the 1-day strength was the slurry concentration, while the  7-day and 28-day strengths, and bleeding rate were most affected by the fly ash content. The factor that had the greatest influence on the slump and diffusion of the paste was the fluorogypsum content. The uniaxial failure of the backfill was shear failure, with cohesion and internal friction angles of 2.02 MPa and 32.6°, respectively. The hydration products included ettringite, calcium sulfate dihydrate and calcium silicate hydrate gel. During the hydration process, the fluoropgypsum consolidated body was transformed from an anhydrous phase to a di‐hydrous phase, where the increase of ettringite and calcium silicate hydrate gel formed a dense structure, im‐proving the strength of the backfill. Conclusions The filling material prepared with fluoropgypsum and fly ash instead of cement was feasible and had a low cost. The solid waste content exceeded 90%, bringing significant economic benefits and promising application prospects.