Feather-shaped directional soft rock tunnel advanced grouting pre-reinforcing structure and method

Abstract

The invention provides a feather-shaped directional soft rock tunnel advanced grouting pre-reinforcing structure and method, and belongs to the field of underground engineering and geotechnical engineering construction. The reinforcing structure comprises a feather-shaped directional grouting drill hole (1), a flexible drilling tool (2), a directional drill bit (3) and a drill bit guide controller (4), wherein the feather-shaped directional grouting drill hole (1) comprises a center drill hole and a plurality of branch drill holes dispersed towards the periphery; the center drill hole is a long drill hole which is pre-drilled by a drilling machine and is consistent with the axial length direction of a tunnel; a steel protection tube for protecting the well wall is put into the long drill hole; the branch drill holes are a plurality of bent drill holes which extend from the center drill hole to the periphery and point to the inner wall of the tunnel (6); the number of the branch drill holes in the circumferential direction of the center drill hole is 2 to 6; the branch drill holes are uniformly distributed in the axial length direction of the center drill hole; and the integral structure of the center drill hole and the branch drill holes is of a feather-shaped structure; grouting is performed in the branch drill holes to form the reinforcing structure.

Description

technical field [0001] The invention relates to an advance grouting pre-reinforcement method for a plume directional soft rock tunnel, belonging to the field of underground engineering and geotechnical engineering construction methods. Background technique [0002] For soft rock tunnels, due to the low strength of surrounding rock and poor self-stabilization ability, construction risks and construction quality problems such as collapse and large deformation are likely to occur. Grouting pre-reinforcement treatment, the grouting holes are arranged in a quincunx shape on the face of the tunnel, and the drilling holes are used to inject cement slurry to reinforce the surrounding rock in front. However, due to the limited space on the tunnel face, it is difficult to locate construction equipment, which brings great difficulties to the construction. At the same time, a large number of grouting holes need to be constructed, resulting in waste of engineering quantity and materials,...

AI Technical Summary

Problems solved by technology

However, due to the limited space on the face of the tunnel, it is difficult to install construction equipment, which brings great difficulties to the construction. At the same time, a large number of grouting holes need to be constructed, resulting in waste of engineering quantity and materials, and poor economic benefits.

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