Disaster Control of Roof Falling in Deep Coal Mine Roadway Subjected to High Abutment Pressure

Abstract

The roof falling accident is a serious threat to the lives of miners in deep coal mining, especially when the coal mine is more than 1000 meters deep. In regard to the 5306 coalface in the Tangkou coal mine, Shandong, China, the depth of coal seam is 992.8 m and the stress concentration coefficient of the roadway surrounding rock is 3.33. This leads to a serious deformation of the roadway roof, thereby producing a high risk of the roof falling disaster. In this pursuit, based on the mechanical analysis of roadway roof subjected to a high abutment pressure, the mathematical expressions of the setting load and movable column length of supports were introduced. Furthermore, the stability control mechanism of the roadway roof was analyzed and the optimized support parameters of supports are provided. The results showed that the longtime effective support of the roadway roof required the strength and deformation coupling of supports and anchored surrounding rock. The support length of the belt roadway should be at least 57.7 m, with 0-30 m away from the coalface supported by hydraulic supports and 32-57.7 m supported by single props. In addition, the maximum setting load and movable column length of hydraulic supports were 21.67 MPa and 280.3 mm and 12.44 MPa and 177.1 mm for single props, respectively. By applying the optimized support parameters of supports to the belt roadway of the 5306 coalface, the effective control of the roadway roof and the disaster control of roof falling were realized.

Dynamic Pressure Manifestation Mechanism and Control Techniques for Roadways with Large Mining Heights and Intense Mining: A Case Study

“…Since roadways are a key component of the production and transportation system in coal mines, improving their safety, reliability, and stability is of great importance for coal mine production. With the recent increase in coal mining depths and intensity; however, dynamic pressure phenomena such as rib spalling, floor heave, and roof fall have appeared frequently in roadway surrounding rock, posing serious threats to safety and efficient production [1][2][3][4]. In response, many scholars have intensively studied the dynamic pressure manifestation in coal mine roadways.…”

Mining-Induced Stress Control by Advanced Hydraulic Fracking under a Thick Hard Roof for Top Coal Caving Method: A Case Study in the Shendong Mining Area, China

“…Roof accidents have a high incidence and fatality rate, and are the first of the five major disasters in coal mines, especially in the mining of coal seams under thick hard strata [1,2]. However, more than 50% of coal mines are currently operating under thick hard rocks with high strength, undeveloped joints and fissures, good integrity and strong energy storage capacity in China [3][4][5].…”

Optimization of Grouting Material Mixture Ratio Based on Multi-Objective Optimization and Multi-Attribute Decision-Making

“…With the depletion of shallow coal resources, deep coal mining in China is becoming more and more prevalent [7,8]. However, the deep mining of coal resources usually comes with more mine pressure, more complex surrounding rock stress state, greater deformation, and more roof and rib falling risks, which threatens coal mine workers' lives and safety and affects mine production [9][10][11][12][13]. The stability of the roadway surrounding rock is of great significance to the safe production of coal mines.…”