Tunnel IV-type and V-type surrounding rock advanced tied arch damping reinforcing method

Abstract

The invention discloses a tunnel IV-type and V-type surrounding rock advanced tied arch damping reinforcing method. The tunnel IV-type and V-type surrounding rock advanced tied arch damping reinforcing method comprises the steps that firstly, a steel arch frame used for supporting an exposed surrounding rock mass is erected on a tunnel face; then an arched advanced thin-walled groove hole with thecentral angle being 90-180 degrees is excavated in the top of the face and expanded outwards at the angle of 2-5 degrees in the tunneling direction; damping gaskets are mounted on the bottom wall ofthe arched advanced thin-walled groove hole, then trussing beams are mounted on the damping gaskets, and a grouting steel pipe is placed between every three to four trussing beams; backfill grouting is conducted in the arched advanced thin-walled groove hole through the grouting steel pipes, the trussing beams and the grouting steel pipes form a trussing arch body structure through slurry solidifying, then the trussing arch body structure and the steel arch frame are connected together; and finally, tunnel excavation is conducted, and construction is completed. According to the tunnel IV-typeand V-type surrounding rock advanced tied arch damping reinforcing method, safety in the large section excavation construction period and the drilling and blasting construction period of a tunnel canbe ensured; and meanwhile, the possibility of anchorage connection of an arch body and a surrounding rock deep layer is achieved.

Description

technical field [0001] The invention relates to the technical field of tunnel excavation and support, in particular to a shock-absorbing and reinforcing method for an advanced rod system arch in surrounding rocks of Class IV and Class V tunnels. Background technique [0002] Tunnel engineering technology has a long history of development. At present, drilling and blasting, TBM mechanical excavation and other construction methods are the main methods. In the future, hydraulic cutting and laser cutting will also be developed. The above-mentioned drill and blast method mainly uses excavation machinery and explosives to complete the excavation of the tunnel. It has a wide range of applications, but it has a large disturbance to the rock mass; TBM (using tunnel boring machine) is a method that has less disturbance to the rock mass Mechanized excavation technology has high efficiency, safety, and high degree of engineering quality assurance, but the cost is high, and it cannot be ...

AI Technical Summary

Problems solved by technology

The traditional advance small pipe grouting reinforcement method cannot reinforce the whole section of the surrounding rock, and its effect is limited; although the pipe shed method adopts the full section reinforcement, it emphasizes the front and rear beam support, and limits the internal reconstruction of the surrounding rock by installing vertical anchors. Reinforcement methods; at the same time, neither of these two methods can weaken the blasting disturbance

In addition, the pre-cutting method has high cost of hole-forming machinery, and there is no internal reinforcement and shock absorption measures for the surrounding rock

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