Application of Gob-Side Entry Driving in Fully Mechanized Caving Mining: A Review of Theory and Technology

Abstract

China has abundant coal resources, and the distribution of coal seams is complex. Thick coal seams account for more than 45% of all coal seams. Fully mechanized top coal caving mining has the advantages of large production, high efficiency, and low cost. In fully mechanized caving mining, especially in fully mechanized caving mining of extra-thick coal seams, the mining space is ample, the mine pressure is severe, and the roadway maintenance is complex. As a result, it is necessary to summarize and discuss the gob-side entry driving of fully mechanized caving in theory and technology, which will help to promote the further development of fully mechanized caving gob-side entry driving technology. First, in recent years, the research hotspots of gob-side entry driving have focused on the deformation mechanism and the control method of the roadway surrounding rock. Secondly, this paper discusses the theoretical models of the “triangle-block” and “beam” for the activity law of the overlying strata in gob-side entry driving, including the lateral breaking “large structure” model, compound key triangle block structure model in the middle and low position, the high and low right angle key block stability mechanics model, elastic foundation beam model, low-level combined cantilever beam + high-level multilayer masonry beam structure model, and the vertical triangular slip zone structure model. It introduces the “internal and external stress field theory” and the “stress limit equilibrium zone model”. Thirdly, it summarizes several numerical simulation analysis methods in different conditions or research focuses and selects appropriate constitutive models and simulation software. Finally, it introduces surrounding rock control technology, including two ribs, the roof, and under challenging conditions. It provides a method reference for support in similar projects.

Control Effect Analysis and Engineering Application of Anchor Cable Beam-Truss Structure on Large-Deformation Roadway in Deep Coal Mine

“…According to the position and principle of surrounding rock control of coal mine roadway, the basic support forms of roadway can be divided into fve types [32,33], as shown in Figure 1, namely:…”

The J2 evolution model and control technology of the main roadway surrounding rock under superimposed influence of double-coal seam mining

“…Along with mining, gradually using mature gob-side entry-driving technology is an useful technical means to improve the resource collection efficiency of coal under safe mining 5 , 6 . When applying the technology of digging roadways along the air, the coal pillar’s width to be protected should be reduced as much as possible to guarantee safety; the reasonable design of the coal pillar’s width is the technology’s critical point.…”