高掺量粉煤灰注浆材料在采空区治理中的应用

为减少矿山在综合治理工作中的成本问题,进行“粉煤灰掺量水泥注浆材料配比”实验研究。设计正交实验进行粉煤灰-水泥注浆材料析水率、结实率、抗压强度研究,对各实验方案可行性进行研究,优选出最优方案并进行现场工业实验研究。研究表明:固相比为单轴抗压强度的主要影响因素,水固比为析水率、结实率的主要影响因素,水玻璃掺量对试件抗压强度无显著影响;进行不同固相比、水固比、养护龄期条件下强度的变化模型构建,固相比、水固比、养护龄期与强度呈正相关,固相比系数值最大,表明固相比对强度的影响最为显著;选择使用二级粉煤灰,固相比4∶6、水固比1∶1.4的方案最优,并进行工业实验,均满足现场需求。目前该矿山正逐步将此法推广到矿山其他充填接顶区域。

Application of high content fly ash grouting material in goaf treatment

In order to reduce the cost of mine in comprehensive treatment work, the experimental study of "the proportion of cement grouting material with fly ash content" was carried out. The orthogonal experiment was designed to study the water precipitation rate, seed setting rate and compressive strength of the fly-ash - cement grouting material. The feasibility of each experimental scheme was studied and the optimal scheme was selected and the field industrial experiment was conducted. The results show that the solid ratio is the main influencing factor of uniaxial compressive strength, the water-solid ratio is the main influencing factor of water extraction rate and seed setting rate, and the water glass content has no significant influence on the compressive strength. The strength change model was carried out under the conditions of different solid ratio, water-solid ratio and curing age. Solid ratio, water-solid ratio and curing age were positively correlated with strength, and the value of solid ratio coefficient was the largest, indicating that solid ratio had the most significant influence on strength. Second grade fly ash, solid ratio 4:6, water solid ratio 1:1.4 and water glass content 0% were selected as the optimal scheme, and industrial experiments were conducted to meet the site requirements. At present, this method is gradually applied to other filling roof areas in the mine.