Distribution Characteristics and Variation Law of Surrounding Rock Loosening Circle at 1438 m Level in Jinchuan No.3 Mining Area
In response to the impact of differences in surrounding rock loosening circle in the roadway support of Jinchuan No.3 mining area,a 1438 m horizontal roadway was taken as the research object,and on-site testing of the loosening circle was conducted using acoustic testing method.The thickness of the two sides of the loosening circle in different surrounding rock roadways was obtained.A numerical calculation model for the loosening circle in different surrounding rock roadways at the 1438 m level was established,and the distribution characteristics of different surrounding rock loosening circles and the influences of rock mechanics parameters on the thickness of the loosening circle were studied.The research results are drawn as follows.Firstly,the thickness of the loosening circle at the floor of 1438 m level in Jinchuan No.3 mining area is the largest,followed by the roof,two sides,and arch shoulder,and the thickness of the loosening circle at the bottom corner is the smallest.Secondly,the thickness of the loose ring in mixed rocks is generally larger at different positions,followed by ultrabasic rocks,and the thickness of the loosening circle in amphibolites is generally smaller at different positions.Finally,the thickness of the loosening circle decreases exponentially with the increase of cohesion and internal friction angle.The rate of decrease in cohesion slowly decreases,and the rate of decrease in internal friction angle slowly increases.The research results can provide a theoretical basis for the design of support schemes for surrounding rock roadways in the No.3 mining area.
Jinchuan No.3 mining areaRoadway supportThickness of loosening circleDistribution characteristicsNumerical simulation
万方数据
维普
