Development and application of a mechanical performance testing system for rock bolt composite components and metal mesh

To test anchor combination components and metal mesh in case of support failure in complex and difficult roadway support process, a static loading test device for anchor combination components and metal mesh was developed, and a series of vertical load tests for support components was carried out. The mechanical response characteristics of support components under vertical load have been obtained. Firstly, a mechanical performance test bench for anchor support combination components and metal mesh static load was developed, and then a set of boundary fixing methods for metal mesh and anchor rod support combination components was proposed. The developed testing system can restore the stress state of underground metal mesh and anchor support combination components more realistically. During the load-bearing process of reinforced beams, the load changes are mainly divided into three stages: slow rise stage, constant speed rise stage, and instantaneous failure stage. The load variation of W-shaped steel strip also goes through three stages: bearing stage, long hole sliding stage, and long hole tearing stage. By increasing the diameter of the steel bar support beam and the thickness of the W-shaped steel strip, the support strength and stiffness of the support system can be effectively improved. Among them, the weak strength areas, such as the welding parts of the steel bar support beam bracket and the long hole ends of the W-shaped steel strip are the key factors affecting the support strength and stiffness. The load displacement curves of different types of metal mesh support systems under vertical loads are mainly divided into three stages: load transfer stage, mesh deformation stage, and structural failure stage; Steel mesh has high stiffness support characteristics, diamond mesh has high strength support characteristics, and the continuous displacement of mesh wires under load is the main factor weakening the support strength and stiffness of the warp and weft mesh support system. The shear and tensile breakage of mesh wires at the tray position is the main factor causing the failure of the metal mesh support system.