Shallowly buried small-spacing rock soil tunnel construction method

Abstract

The invention relates to a tunnel construction method, in particular to a shallowly buried small-spacing rock soil tunnel construction method. According to the technical scheme, the shallowly buried small-spacing rock soil tunnel construction method comprises the steps of 1, measuring and setting out; 2, open cutting and supporting at a tunnel portal section, wherein the step of open cutting and supporting at the tunnel portal section comprises the sub-steps that the open cutting is conducted by the cooperation of manpower and machinery, slope cutting is conducted, portal face supporting is formed by adopting a large pipe shed and a steel arch, therefore an open hole is formed, and the step comprises the sub-steps of advanced pre-reinforcement of the large pipe shed and advanced construction of small pipes; 3, shallowly buried small-spacing tunnel excavation; 4, reinforcing of tunnel vault and tunnel spacing rock; 5, monitoring and measuring; 6, secondary lining concrete construction. The shallowly buried small-spacing rock soil tunnel construction method is beneficial for safety construction and improving economical benefits.

Description

technical field [0001] The invention relates to a tunnel construction method, in particular to a shallow-buried rock-earth tunnel construction method with small spacing. Background technique [0002] Due to the impact of topography, or in order to reduce land acquisition and demolition, the shallow buried and small-spaced tunnel scheme can not only solve the terrain constraints, reduce the excavation and backfilling of earth and stone, and reduce the damage to the surrounding environment, Moreover, it can reduce the cost of land acquisition and demolition, and reduce the scope of impact of blasting. [0003] With the continuous development of tunnel engineering technology, there are shallow buried and small spacing tunnels in the tunnels of highways, railways, rail transit, water conservancy, nuclear power and other projects. Difficulties, in the case of relatively poor geological conditions, if the thickness of the rock pillars between the old and new tunnels is not enough...

AI Technical Summary

Problems solved by technology

[0003] With the continuous development of tunnel engineering technology, there are shallow buried and small spacing tunnels in the tunnels of highways, railways, rail transit, water conservancy, nuclear power and other projects. Difficulties, in the case of relatively poor geological conditions, if the thickness of the rock pillars between the old and new tunnels is not enough, when the tunnel is excavated, the surrounding rock plastic zone around the contour line is too large, or even runs through the rock pillars, which will lead to plastic failure of the structure ; In addition, after the excavation of the old and new tunnels, the rock pillars between the old and new tunnels will bear huge vertical pressure without lateral constraints. When the rock pillars are narrow in width, they can be regarded as slender Unconfined compression of components, when there is a bias, it is easy to lose stability and damage; small-spacing tunnels are prone to engineering accidents such as rock pillar damage between tunnels, tunnel blasting operations that are constructed later, and tunnels that are constructed earlier; There are engineering accidents such as roof fall, surface subsidence, and upper surrounding rock stepping into the air; the occurrence of the above-mentioned accidents brings great safety hazards to the construction, and also increases the rescue costs and follow-up support costs after the accident, which is not conducive to the protection of the surface environment. Not conducive to engineering construction safety