Study on stability of overlying rock structure in fully mechanized top coal caving mining under loess gully landform

Abstract

In view of the obvious characteristics of mining pressure in Wangjialing Coal Mine under the loess gully landform, the Get Data software was used to extract the elevation data within the mining range, and Surfer was used to process the data to construct the loess gully three-dimensional landform; based on numerical simulation technology, the influence of loess gully landform on the stability of overburden structure in fully mechanized top coal caving mining was studied. The results show that the loess gully landform has a significant effect on the original rock stress in the mining area, and the effect gradually decreases with the increase of mining depth; it shows that the shallow original rock stress is mainly affected by the loess gully landform, and the deep original rock stress is mainly related to the buried depth of rock strata. Under the influence of loess gully landform, with the advance of mining face, the overlying strata are subjected to more and more force, the key strata begin to lose stability and fracture, the arch area with the most serious subsidence of goaf continues to lag behind the geometric middle of goaf, and the concentration degree of advance abutment pressure of working face is obviously affected by the thickness of overlying loess layer.

Keywords

• loess gully landform
• fully mechanized top coal caving
• overburden structure
• flac
• original rock stress field