渗流作用下软弱覆岩相似模拟实验研究

Study on Similar Simulation Experiment of Weak Strata Under the Action of Seepage

针对含水层下采场软弱覆岩破坏特征及透水机理问题,利用二维物理相似模拟实验对其综放开采过程进行探究,分析了导水渗流区域的形成机理,探讨了导水优势路径的判断依据。实验探究表明:渗流作用下覆岩受采动破坏影响出现裂隙发育区,裂隙压实区和潜在裂隙区等裂隙运移区域。地表至煤层方向,自上而下覆岩裂隙率逐渐增大,水体沿着裂隙率较大的导水优势裂隙渗流至采空区。渗流区域在隔水层之上呈"漏斗状"分布,在隔水层下大致沿着岩层断裂线所形成的"破坏拱"分布,水流渗透痕迹由"破坏拱"从内至外逐渐消散。煤层走向方向上,涌水量的相对大小关系为开切眼一侧>采空区上覆岩层>停采面一侧。

Aiming at the failure characteristics and the water permeation mechanism of the weak overburden in the aquifer, in this paper, two-dimensional physical similarity simulation experiment is used to explore the mining process. The formation mechanism of the seepage flow area is analyzed, and the judgment basis of the dominant route of water diversion is discussed. The experimental study shows that under the action of seepage, the fractured area of fissure development area, fissure compacting area and potential fissure area are affected by mining failure. From surface to coal seam direction, overburden fissure gradually increased from top to bottom, the water seeps along the fissures with larger crack rate into goaf. The seepage area is distributed in the＂funnel＂distribution above the aquifer, and the＂broken arch＂is formed along the fault line of the formation. The trace of water flow gradually dissipated from the inside of the＂broken arch＂to the outside. In the direction of coal seam, the relative size of the gushing water is the side of the open-off cut 〉the overburden area of the goaf area the side of the stop mining face.