关键词: 沿空留巷, 巷旁支护体, 破坏规律, 数值模拟

Abstract: In order to acquire the regularity of deformation and destruction of the support in gob-side entry retaining, FLAC^3D has been used to build the model of roadside support. By using trial method, the reduction function relationship between cohesion of the model and interior angel and plastic sheer strain has been obtained, which helped to ensure that the stress-strain relationship gained from numerical model and filling materials in the physical compression test is consistent with the fracture law. Based on such parameters, the deformation and destruction characteristics under different end constraints and inclination angles have been analyzed. The main conclusions are as follows. Without end restraint, the stress distribution within support before peak is approximately uniform with unlimited lateral deformation, and the dip angle does not have obvious impact on the peak load before plasticity. With end constraints, the peak stress of support increases a little and lateral inhomogeneous deformation occurs. The destruction forms of the support differ according to different angles: when the angle is between 0° and 10°, multiple shear failure occurs; when it is between 10° and 25°, the double crack shear failure is produced; when it is greater than 25°, the top-bottom boundary friction shear failure presents. Additionally, due to the slope of coal seam, with end restraints, the stress concentration of sharp angle is higher, so it should be reinforced during supporting.

Key words: goaf-side entry retaining, roadside support, failure laws, numerical simulation