薄煤层充填开采超高水材料配比及充填工艺优化

Super High-water Material Ratio and Optimization of Filling Technology in Thin Coal Seam Filling Mining

为解决超高水材料在现场施工过程中易出现浆液泌水、甚至不凝固影响充填体强度等问题,进行优化材料配比试验,并在此基础上进行泌水率测试和不同搅拌工艺试验,以提高现场充填效果。试验结果表明:B料中石膏∶石灰比例为4∶1时,超高水材料的抗压强度最大;搅拌工艺对材料泌水率存在较大影响,合理的增加混合浆液搅拌时间能有效减少泌水率,进而减少添加剂掺量、减少成本。将改善后的材料配比及充填工艺应用于田庄煤矿薄煤层充填开采工作面,通过现场取样测试充填体强度和监测得到的实时顶底板移近量数据,充填体强度高于实验室强度,顶底板移近量仅为96 mm,取得了良好的充填效果。

In order to solve the problems such as the occurrence of slurry bleeding and even the impact of non-solidification on the strength of backfill in the field construction of ultra-high water materials,based on this,the optimized material ratio test was carried out,and on the basis of the bleeding rate test and different mixing process tests to improve on-site filling results.The test results show that:when the proportion of gypsum and lime of B material is 4∶1,the compressive strength of super high-water material was the largest;the stirring process had a great influence on the bleeding rate of the material,and reasonable increase of the mixing time of mixing slurry could effectively reduce bleeding rate,which could greatly reduce the amount of additives.The improved material ratio and filling process were applied to the thin coal seam filling mining face of Tianzhuang Coal Mine.The strength of backfill was tested by field sampling and the real-time data of top and floor displacement obtained by monitoring showed that the strength of backfill was higher than that of the laboratory,and the top and floor displacement was only 96 mm,achieving a good filling effect.