A kind of tunnel cracked secondary lining reinforcement method and device based on sprayed cement-based composite material

Abstract

The invention discloses a method and a device for reinforcing a cracked secondary lining of a tunnel based on a spray-type cement-based composite material, belonging to the technical field of underground engineering. The present invention carries out the pretreatment of reinforcement technology for the cracked secondary lining of the tunnel and the reinforcement spraying construction for the secondary lining of the cracked tunnel. The treated surface of the secondary lining of the tunnel is subjected to inclined drilling treatment; then, drill holes again on the surface of the secondary lining of the tunnel after chiseling treatment and lay high-strength anchoring steel nails in it; finally, the cement-based composite material is sprayed onto the treated secondary lining of the tunnel. Reinforce the lining surface. The reinforcement method has little disturbance to the original structure, ensures the stability, safety and durability of the structure, reduces the impact on the operation of the tunnel, and ensures the integrity of the tunnel lining. The use of an integrated device for stirring and spraying construction with screening function can improve construction efficiency and ensure that the freshly mixed mixture has good working performance.

Description

technical field [0001] The invention belongs to the technical field of underground engineering, and in particular relates to a method and a device for reinforcing a cracked secondary lining of a tunnel based on a spray-type cement-based composite material. Background technique [0002] Concrete is widely used in tunnel engineering due to its wide access to raw materials, simple preparation process and high strength. However, ordinary concrete is a brittle material with extremely poor toughness and ductility, and the ultimate tensile strain is about 0.01%; although the importance of controlling the crack width has gradually attracted attention in the durability of infrastructure, it is not widely used in the design of concrete. Not enough attention has been paid. When the tensile strain of ordinary concrete is about 0.01%, the width of local cracks has exceeded 0.6mm, which seriously affects the bearing capacity and durability of the structure. [0003] Due to the low toughn...

AI Technical Summary

Problems solved by technology

Utilize sprayable high-toughness, anti-seepage and low shrinkage cement-based composite materials to replace traditional concrete materials for tunnel cracked secondary lining reinforcement, fundamentally solve the cracking of tunnel lining and repeated cracking after reinforcement with ordinary concrete In addition, a new type of mixing and spraying construction integrated device was invented for the application of high toughness cement-based composite material spraying reinforcement, and a detachable stainless steel screen was attached to ensure the uniformity of aggregate particle size, solving the problem of high toughness, Problems of anti-seepage and low shrinkage cement-based materials in the construction process of mixing and spraying construction and improving construction efficiency

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