Active support using highly prestressed cable bolts and anchor cables has become a mainstream support technology for coal mine roadways. However, the ability of bolts and anchor cables to withstand transverse shear decreases with the prestress level, jeopardizing mining safety. This study proposed a technical solution to this problem featuring anchor cables enclosed in an axisymmetrical tube with a C-shaped cross-section (ACC), which are highly prestressed and can withstand high transverse shear. The ACC mechanical performance was tested in the #318 gas extraction roadway of the Shuangliu Coal Mine, China, characterized by extensive deformation under original support conditions. Theoretical analysis, laboratory tests, numerical simulation, and field tests were performed to analyze the shear mechanical properties of the ACC and anchor cables alone. The double shear test results revealed that the proposed ACC scheme increased the transverse shear resistance and stiffness by 10–25% and 20–40%, respectively. The FLAC^3D numerical simulation showed that the roof-and-floor and rib-to-rib convergences decreased by 9.53 and 25.11%, respectively. The area of the stress concentration zone also decreased. Field monitoring showed that the ACC achieved good support performance. During the monitoring period, the maximum roof-and-floor and rib-to-rib displacements were 40 and 49 mm, respectively. The ACC scheme offered adequate shear resistance and effectively controlled surrounding rock deformation in the gas extraction roadway under study, making it applicable to similar engineering scenarios.

The stability of roadway is of great significance to mine safety production. In this paper, according to the geological conditions of Xinyu coal mine, the cross-section form of track roadway is optimized. Under the condition of the same ratio of height to width, rectangular section, circular arch section and straight wall semicircular arch section are designed respectively. FLAC3D is used to establish numerical model to simulate three kinds of section forms. The optimal section form is obtained by analyzing displacement field, plastic zone distribution and stress field. The results show that: (1) The cross-section form of coal mine roadway is an important factor affecting the stability of roadway. (2) Under the same ratio of height to width, the stability of roadway from high to low is straight wall semicircular arch, circular arch and rectangle. (3) The field test data show that the straight wall semicircular arch roadway has good engineering effect. (4) Comprehensive comparison shows that the straight wall semicircle arch is the best roadway section form. The research results can provide reference for the design of roadway section form in the future.

With the exploitation of coal resources in Western China, the local water shortage and loss are becoming more and more serious. In order to protect water resources, coal mine underground reservoirs came into being. As the main part of underground reservoir in coal mine, the stability of artificial dam is of great significance. The dam thickness is a key parameter of the artificial dam, which is closely related to stability of the dam. Taking Wulanmulun mine as the engineering background, the artificial dam model is established by FLAC3D software. The mechanical response and deformation law of the dam under different thickness are analyzed from three aspects of displacement, stress and plastic zone. The results show that the increase of dam thickness can reduce the displacement and stress level of dam and groove, and reduce the distribution of plastic zone. In comprehensive consideration, the thickness of the artificial dam can be increased to 1.4m to improve the stability of the dam.