From the following equation (10), it is obvious that Δu is related to H, M, and KP, where h0 is the thickness of the immediate roof, m; KP is the loosening coefficient of the broken rock seam, 1.5. Then, the calculation of a can be given with the geometric relationship after the...
The fracture of rocks surrounding the floor roadway during the mining of the working face of a coal mine is a complicated spatiotemporal process due to the superimposed action of multiple stress fields on the surrounding rock mass. Using the surrounding
The invention relates to a method for controlling deformation of a large broken rock zone roadway by using a multi-steel stranded wire combined supporting device. The method includes the steps of determining damage conditions of surrounding rock of the roadway by combining various methods, building ...
The discontinuity of rock materials (such as joints, cracks, bedding and different mineral compositions) cause continuum mechanics to exhibit significant deficits. Compared with the finite element method (FEM), the discrete element method (DEM) not only can represent the broken states and the strong...
integrity of the coal body is basically unchanged and the fracture is not extended after blasting. In other words, the blasting had no effect on the coal body. In contrast,kv→ 0 shows that the coal body is severely broken after blasting, and the blasting had a strong effect on the coal...
It is required to have a kind of high-strength support material with an anchorage range larger than the depth of the penetrating plastic zone and not broken during the deformation process. 5. Field Application and Effect Analysis According to the plastic zone penetration development of the ...
The two sides of the reserved roadway at 1523103 are mostly fractured bodies or even broken bodies. The mine pressure characteristics of the surrounding rock of the reserved roadway mainly depend on the occurrence and development of the deformation and failure of the two sides of the coal body....
The single hydraulic prop is often equipped with a hinged top beam (one or cross beam) for advanced support. The support form is “point” support, the support strength is small, and the manual handling method is adopted. The support process involves two steps: “support” and “return ...