# Research on the required width of a fault waterproof coal pillar based on underground pressure control theory

• Longqing Shi
• Ying Wang
• Mei Qiu
• Lu Han
• Yunping Zhao
ISMSSE 2018
Part of the following topical collections:
1. Mine Safety Science and Engineering

## Abstract

Based on underground pressure control theory, this paper expounds the distribution characteristics of abutment stress and the resulting damage to a coal seam in front of a working face. In addition, the distribution and propagation features of vertical underground pressure in floor strata is characterized by simulation results obtained from 2D-σ finite element analysis software. Numerical simulation reveals that the peak stress line of the vertical underground pressure is inclined toward the coal mining direction of the working face. Based on the establishment of a mechanics model for water inrush from floor aquifer through a fault in a stope, a formula for calculating the distance between the bottom of the coal seam and the intersection point of the peak stress line with the fault is derived. The condition allowing water inrush from a floor aquifer through a fault is described as follows: the destroyed floor depth caused by underground pressure is not less than the distance between the bottom of the coal seam and the intersection point of the peak stress line with the fault. The water inrush pathway is composed of the fault and the floor strata destroyed by underground pressure. Based on gray multivariate nonlinear regression analysis, the formula for calculating the destroyed floor depth with four main factors is deduced: these factors are the mining depth, dip angle of the coal seam, inclination width of the working face, and Platts’ coefficient of the floor strata. According to the mechanics model for water inrush from a floor, the formula for a fault waterproof coal pillar in a stope is presented, and the rationality of the model and formula has been verified by cases of water inrush from floor aquifers in the Suncun Coal Mine and the Xiaoyun Coal Mine, China.

## Keywords

Abutment stress distribution characteristics Water inrush model through a fault Destroyed floor depth Fault waterproof coal pillar

## Notes

### Funding information

This study received financial support from the National Natural Science Foundation of China (no. 41572244, no. 51804184, no. 41807283), the Scientific Research Foundation of Shandong University of Science and Technology for Recruited Talents (2017RCJJ033), the Open Fund Research Project of State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology (MDPC2017ZR05), and Taishan Scholars’ Special Funds for Construction Projects.

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© Saudi Society for Geosciences 2019

## Authors and Affiliations

• Longqing Shi
• 1
• Ying Wang
• 1
• Mei Qiu
• 1
• 2
Email author
• Lu Han
• 1
• Yunping Zhao
• 1
1. 1.State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and TechnologyShandong University of Science and TechnologyQingdaoChina
2. 2.Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Minerals, College of Earth Sciences & EngineeringShandong University of Science and TechnologyQingdaoChina