粉煤灰基胶结充填材料试验研究

黑龙江科技大学 矿业研究院,黑龙江 哈尔滨 150022

充填材料; 粉煤灰; 活化剂

Experimental research on fly-ash-based cement filling material
LI Feng-yi,CHEN Wei-xin,LIU Shi-ming,GUAN Xian-hua

(Mining Research Institute,Heilongjiang University of Science and Technology,Harbin 150022,China)

filling material; fly ash; activator

DOI: 10.13800/j.cnki.xakjdxxb.2015.0412

备注

针对目前性能优良的矿用胶结充填材料价格较高的问题,通过试验室正交实验的方法得到粉煤灰未经活化的最佳组分配比,而后通过对比实验找到1种粉煤灰活化剂,这种活化剂与粉煤灰、水搅拌陈放4~8 h后,能有效激发组分配方中粉煤灰的早期活性,活化后粉煤灰掺入组分配比后得到水灰比接近1:1,粉煤灰占充填材料固体质量80%以上,8 h抗压强度大于0.8 MPa,1 d抗压强度大于3 MPa,3 d抗压强度大于4 MPa,初凝时间在90~120 min之间的材料配方。结果 表明:材料8 h即形成大量针状钙矾石,3 d时产生C-H-S(水化硅酸钙)凝胶,7 d后钙矾石已被胶凝包裹。最后,按配方比例在桃山矿井下采空区进行充填工业试验,该材料虽掺入大量粉煤灰但仍能适应井下环境,具有快凝、早强、接顶率高等特点。

Aimed at the high price of better cementing filling material in the mine,the paper got the best ratio of fly-ash without activation by orthogonal experiment,then found a activator for fly-ash by comparative experiment,which mixed with fly-ash and water after 4 hours to 8 hours can excite the early activity of fly ash efficiently.When the activited fly ash would be mixed component Formulation,the optimum formula was obtained that the water-solid ratio approached to 1 and fly ash accounted for over 80% of solid mass in filling material; the compressive strength was more than 0.8 MPa after 8 h,more than 3 MPa after 1 d,and more than 4 MPa after 3 d; initial setting time is about 90 min to 120 min.Micro-analysis results showed that the materials formed a lot of needle ettringite after 8 hours and produced C-H-S gelation(calcium silicate hydrate)after 3 d,ettringite was wrapped by gelling after 7 d.The scheme is tested by backfill mining in underground of Taoshan mine according to the ratio formula,which proves that the material with large amounts of fly ash can adapt the environment in underground mine with advantages of rapid solidification,early strength and high rate of supporting,which can satisfy the basic requirements of filling coal.