The combined support of U-shaped steel arch support, metal mesh, and shotcrete has changed the limitations of the three support forms used alone, and gave full play to the advantages of the three support forms, greatly enhancing the ability of the roadway to resist deformation and damage. The U-shaped tunnel roof support increases the rigidity of the supporting roadway, and makes full use of the support's own bearing capacity to resist the pressure of the surrounding rock of the roadway; the main function of the shotcrete is to seal the surrounding rock, so that the U-shaped tunnel roof support, metal mesh and surrounding rock are firmly bonded; the metal mesh increases The tensile, shear strength and resistance to elastic deformation of shotcrete.
So far, the roadway has a small amount of deformation, no cracks, and no concrete falling off. It shows that the combined support of U-shaped support arch and metal mesh shotcrete is successful.
(1) U-shaped support arch and metal mesh shotcrete combined support technology is adopted to reduce the amount of surrounding rock excavation, and the construction speed is fast and the efficiency is high. Compared with the masonry support, in the reconstruction and expansion of the belt conveyor head section, the U-shaped tunnel roof support and the metal mesh shotcrete combined support are adopted, which reduces the amount of surrounding rock excavation works, basically implements mechanized operations, and reduces the number of workers. Labor intensity eliminates the need for mold erection and mold disassembly procedures, and does not affect the normal operation of the belt conveyor.
(2) The use of this new type of steel arch support technology has high initial costs, but the roadway has a long service life, small roadway deformation, and few roadway repairs; the roadway support thickness is small, the amount of surrounding rock excavation is small, and the comprehensive benefits of roadway support are good.
(3) Adopting this new type of supporting technology, the distance between empty roofs is reduced and the safety of construction personnel is ensured.
