Study on Influence Laws of Strata Behaviors for Shallow Coal Seam Mining beneath Gully Terrain

Zhiqiang Wang,Zhen Li,Jiao Zhang,Hengzhe Qu,Chao Wu,Jingkai Li,Peng Wang,Wenyu Lv,Xuepeng Zhang

doi:10.1155/2021/3954659

Zhiqiang Wang, Zhen Li + Show 7 more

Open Access

https://doi.org/10.1155/2021/3954659

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Abstract

The study on influence laws of strata behaviors is the basic guarantee of safety mining for shallow coal seam beneath gully terrain. Taking 3302 mining face of Zhujiamao Coal Mine as the engineering background, the laws of strata behaviors for shallow coal seam mining beneath gully terrain are studied by field detection, theoretical analysis, and numerical simulation. The strata pressure observation and the hydraulic support working resistance show that the dynamic strata behaviors appear violently during mining beneath the gully bottom. The theoretical analysis shows that the rotation and breaking of key stratum beneath gully bottom under nonuniform load is the fundamental cause of strong dynamic strata behaviors. The numerical simulation of overburden movement and fissure development characteristics shows that the strata behaviors beneath the gully bottom are stronger than the strata behaviors beneath other areas. Additionally, according to the laws of dynamic strata behaviors, the safety measures for mining beneath gully bottom are put forward.

Highlights

In China, the coal in the eastern region has been nearly mined out, and the coal mining has been transferred to the western region, which is rich in coal reserves and has become a new energy base [1,2,3,4]
In order to provide theoretical basis and technical support for shallow coal seam mining beneath gully terrain, this paper studies the mechanism and laws of strata behaviors on the basis of previous research achievements
The advancing distance is different, the fissures are dominated by longitudinal fissures and the degree of fissures development is obviously improved during mining beneath gully bottom, which fully indicates that the strong dynamic strata behaviors are caused by the breaking of the key stratum

Summary

Introduction

In China, the coal in the eastern region has been nearly mined out, and the coal mining has been transferred to the western region, which is rich in coal reserves and has become a new energy base [1,2,3,4]. Erefore, it is necessary to study the influence laws of strata behaviors for shallow coal seam mining beneath gully terrain. In order to solve the above technical problems, for shallow coal seam, the identification method of key strata has been modified [30], the mechanical model of stope roof has been established [31], the concept of water retaining mining has been put forward [32], the development law of “three zones” has been studied [33], and the safety mining technology of close-distance seam group has been explored [34]. In order to provide theoretical basis and technical support for shallow coal seam mining beneath gully terrain, this paper studies the mechanism and laws of strata behaviors on the basis of previous research achievements. The safety measures for shallow coal seam mining beneath gully bottom are put forward

Study Site

Field Detection

15 Upper support Middle support Lower support Weighting criterion

Numerical Simulation

Findings

Conclusions