Ice-water accumulation body tunnel surrounding rock reinforcing and excavating method under influence of seasonal rainfall and surrounding rock support

Abstract

The invention relates to an ice-water accumulation body tunnel surrounding rock reinforcing and excavating method under the influence of seasonal rainfall and a surrounding rock support. The reinforcing method comprises the following steps of S1, constructing a grout stopping wall; S2, arranging a radial grouting guide pipe on a primary support, and conducting grouting reinforcement; S3, conducting advanced drilling and curtain grouting reinforcement; S4, constructing pipe shed holes in the outer arch part of an excavated contour line; S6, arranging pipe shed steel pipes in a driving mode, andconducting pipe shed grouting; and S7, additionally arranging advanced small guide pipe grouting supports on the arch part and side walls. According to the excavating method, surrounding rock is reinforced by adopting above reinforcing method, temporary cross braces are erected in a tunnel, the grout stopping wall is broken, and excavation is carried out by adopting a small-section three-step method. The surrounding rock support comprises the grout stopping wall, a waterproof curtain, a grouting section which is a radial grouting guide pipe grouting supporting section, a pipe shed steel pipecurtain grouting supporting section, and an advanced small guide pipe grouting supporting section. In the curtain grouting process, grout can be prevented from flowing back to squeeze and crack a primary support behind a tunnel face.

Description

technical field [0001] The invention relates to a method for reinforcing the surrounding rock of an ice-water accumulation tunnel under the influence of seasonal rainfall. [0002] The invention also relates to a method for excavating surrounding rock of an ice-water accumulation body tunnel under the influence of seasonal rainfall. [0003] The invention further relates to a surrounding rock support for ice-water accumulation tunnels under the influence of seasonal rainfall. [0004] The invention further relates to a method for reinforcing the surrounding rock of an ice-water accumulation body tunnel in a dry season. Background technique [0005] More and more tunnels will inevitably be built in complex hydrogeological environments. Among them, the ice-water accumulation body is a common type of typical unfavorable geological bodies. It was mainly formed during the Quaternary interglacial period. It is composed of a large amount of loose matter transported by glacial mel...

AI Technical Summary

Problems solved by technology

If the entire section of the tunnel passing through the ice-water accumulation body is reinforced according to the risk situation in the dry season, it will be difficult to guarantee the construction safety in the water-rich season; Reinforcement design, on the one hand, will inevitably cause large-scale waste of engineering costs during the dry season, on the other hand, it will seriously drag down the construction efficiency, and it is difficult to guarantee the construction quality of surrounding rock reinforcement

Regarding the above methods of strengthening and excavating the surrounding rock of ice-water accumulation tunnels under the influence of seasonal rainfall, there is still a lack of relevant engineering experience in China, so it is urgent to solve this problem

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