Numerical Simulation Research on Large Cross Section T-type Roadway Surrounding Rock Intersection Instability Control

To solve the problems of large span, difficult control of surrounding rock in T-type roadway intersection, combining methods including theoretical analysis, computer simulation and field measurement are adopted to study the failure characteristics, control mechanism and control effect of T-type roadway intersection surrounding rock. Research found that: triangular area formed by the intersection of roadways is the most vulnerable area of instability, and damage forms are roof caving and curved sinking and affecting factors are roadway cross-section, rock strength, the crossing angle and depth, etc; based on the principle of strengthening triangle regional support in early two lane intersection, we proposed technology and parameters for T-type roadway intersection main lane, branched lane and triangle mesh and anchor support; numerical simulation and field test shows that after anchor net reinforced support, stress and stress concentration significantly ease roadway displacement in the controllable range, the force environment improved significantly, supporting forms and parameters are more reasonable.