Control of Water Inrush from Longwall Floor Aquifers Using a Division Paste Backfilling Method

Abstract

Aiming at the problem of the safety mining problems of longwall paste filling working face under buildings on high confined water in the Daizhuang Coal Mine, the paste filling mining method was used. A series of theoretical analyses, numerical simulations, and field measurements were applied. The results showed that when the filling interval of the working face increases from 1.2 m to 3.6 m, no significant change is found in the depth of the perforated plastic zone of the floor strata. According to the types of water-conducting cracks in the floor strata of the working face 11607, the floor strata are divided into the floor intact area, the structure developed area, and the floor weak area. Based on that, the measures for preventing and controlling the floor failure in the paste filling working face are proposed. Furthermore, the failure depth of the floor of the test working face was detected by the on-site water injection method, and the results showed that the maximum failure depth of the floor of the test working face was about 3 m.

Fully Mechanized Mining Technology and Practice of Water Conservation with Large Gravity Filling of Aeolian Sand‐Like Paste

“…Compared with strip mining, thickness limiting mining, and other water conservation mining methods [1,2] that reduce the degree of overburden damage at the cost of reducing resource recovery, the back ll mining achieves the e ect of controlling mining damage without losing coal resources by back lling solid or cemented lling materials to the goaf, which is an ideal environment-friendly mining method. In recent years, the back ll mining technology with waste gangue and power plant y ash as the main lling materials has been rapidly developed and applied in coal mining under buildings (structures) and near water in mining areas in central and eastern China [3][4][5][6][7][8][9][10][11][12], which has achieved remarkable economic and environmental bene ts and had a demonstration e ect. In view of the urgent demand of water conservation mining in Northwest Mining Area and the characteristics of extensive occurrence of aeolian sand on the surface, it is imperative to use local materials and use Aeolian sand as filling material to carry out filling mining.…”