The Optimized Roadway Layouts and Surrounding Rock Control Technology of the Fully Mechanized Mining Surface with Large Mining Heights in High-Gas Mines

Abstract

Many problems exist in the layout of working surfaces in high-gas mines, such as the low efficiency of roadway excavation, difficulties in maintenance after excavation, and serious resource wastes due to difficulties in recovering coal pillars between roadways. Taking the project profile in the west wing mining area of Sihe Coal Mine as the background, this work proposed an optimization plan for the staggered-layer arrangement of roadways. The minimum retained size of the coal pillar was calculated through theoretical analysis, and the plastic failure and deformations of surrounding rocks under different coal pillar sizes and roadway layouts were compared based on finite difference numerical simulations. The reasonable retained size of the coal pillar was determined to be 45 m, and the roadway layout was determined according to the distribution of coal and rock strata in the mining field. The technical measures of base angle pressure relief blasting and strengthening support were proposed to ensure the safety and stability of surrounding rocks of roadways during the service period after the layout plan was optimized. Similar simulation tests were used to study the damage deformations and stress changes of the blasting pressure relief floor. On-site tests showed that the optimized roadway layout greatly improved the recovery rate of coal resources. In addition, surrounding rocks had good stability, and they could be simply repaired or serve the next working surface directly without being repaired. These research results provide a scientific basis and useful reference for similar projects.

Study on Characteristics of Front Abutment Pressure and Rational Stop-Mining Coal Pillar Width in Large Height Working Face

“…Based on the limit equilibrium theory and engineering practice [29,30], when the main roadway has just been disturbed, the width of the SMCP is the sum of the excavation stress field range Lr of the main roadway and the range Lw of the FAP (Figure 3). The range of FAP includes the widths of the plastic zone x 1 and the elastic zone x 2 , which can be calculated using the following formulas [31,32].…”

Optimal Layout Methods for Deep Chamber to Separate Coal and Gangue Based on the Weak Stratum Horizon

“…According to the similarity theory, test models should ideally be similar to all physical quantities in engineering practices [24]. However, it is difficult to achieve in testing.…”

Controlled reconstruction and application research of lateral overlying strata structure in high-gas mines with thick-hard roofs for a fully-mechanized top-caving face

“…With increasing mining depths and intensifying mining activities coupled with complex and variable coal seam occurrences in certain areas, significant challenges have arisen during mining operations, such as severe strata behavior, substantial roadway deformation, and excessive corner gas concentration. These challenges pose major obstacles in achieving safe and efficient mining operations [ 4 , 5 ]. To address these issues, extensive research has been conducted by experts and scholars on the dynamic behavior of overlying strata during mining, roadway surrounding rock control, and gas extraction and management.…”