高浓度胶结材料在空洞型采空区中的堆积扩散规律试验研究

Experimental study on accumulation and diffusion laws of high concentration cementitious materials in gobs of large caverns

以大空洞采空区充填治理技术为出发点,选取水泥为胶凝材料,标准砂为骨料,对不同骨料和胶凝材料配比条件下高浓度充填浆液的堆积扩散性能进行研究。结果表明,堆积密度测定仪、倒置混凝土塌落度试验仪、常规混凝土塌落度筒测定的同种参数配比的高浓度浆液的堆积形态可分别概化为"凸"字形、"凹"字形和圆弧形。随着骨胶比的增加,浆液的堆积时间呈增加趋势,浆液塌落度明显减小,浆液堆积高度呈增加趋势,堆积浆液底面直径呈减小的趋势。骨胶比在2.6~3.0时,某一骨胶比下,注浆高度越小,注浆孔孔径越小,浆液堆积高度越大,浆液堆积体底面扩散直径越小,所形成的"凸"字形堆积体更有利于大空洞采空区充填治理中结构的稳定和材料的节约。

Taking the filling treatment technology of large hollow gobs as the starting point, cement was selected as the cementitious ma- terial, and standard sand was the aggregate. The accunmlation and diffusion properties of high-concentration filling slurry under different mixing ratios of aggregates and cementitious materials were studied. Test results show that, the accumulation forms of the high-concentration slurrywith the same parameter ratio can be generalized into convex, concave and arc type by bulk densitometer, inverted concrete slump tester,and conventional concrete slump tester. With the increase in the ratio of aggregates and cementitious materials, the accu- nmlation time of the slurry shows an increasing trend, the slump of the slurry reduces significantly, the accumulation height of the slurry increased, and the diameter of the bottom surface of the slurry decreases. When the ratio of aggregates and cementitious materials is in the range of 2. 6 - 3.0, at a certain ratio, the smaller the grouting height, the smaller the hole diameter of the grouting hole, the larger the slurry accumulation height, and the smaller the diffusion diameter of the bottom of the slurry accumulation body. The convex accumula- tion body formed at this time are more conducive to the structural stability and saving materials in the filling treatment of gobs in large caverns.