Abstract: The plain concrete grouted layer will have a large quantity of small primary cracks in the concrete formed during its solidification, which can reduce the tensile strength and fracture toughness. The wall rock in deep roadway in soft rock will have great deformation and therefore requires a strong support strength and certain deformation degree and toughness of the support material. In view of this, it is proposed to use CTA modified polypropylene (coarse) fiber reinforced concrete to replace plain concrete. A large number of tests show that modified polypropylene (coarse) fiber can function as micro rib and increase both the toughness and strain capacity of the concrete at the same time of improving its strength. The stress simulation analysis of the roadway wall rock indicates that when the excavated roadway is lined by fiber reinforced concrete grouting, the shear failure zone will be transfered to the depth of the wall rock, greatly reducing the shear failure zone at roadway hance. It indicates that when used in the support for deep roadway, fiber reinforced concrete grouting can better depress the failure of the wall rock due to the increased strength and toughness, which can be a reference to engineering practice.

Key words: Deep mine support, Simulation analysis, Concrete, Modified polypropylene (coarse) fiber