High-ground-stress large-deformation tunnel release-resistance combined primary support system and construction method

Abstract

The invention discloses a high-ground-stress large-deformation tunnel release-resistance combined primary support system and a construction method. The system comprises a primary support body which isa steel arch frame and an anchor net spraying combined support system matched with the steel arch frame, the primary support body is provided with a plurality of stress release windows in the side wall section of a tunnel, and the stress release windows located on each side of the primary support body are arranged at intervals in the longitudinal direction of the tunnel. The invention further discloses a construction method of the high-ground-stress large-deformation tunnel release-resistance combined preliminary support system. The system and method have the beneficial effects that non-synchronous deformation of surrounding rock and the primary support body is achieved, deformation of a portion, with a maximum deformation, of the primary support body before the primary support body is looped is effectively reduced, and damage to the primary support body before the primary support body is looped is avoided.

Description

technical field [0001] The invention relates to the technical field of tunnels and underground engineering. In particular, it relates to a primary support system and method suitable for high structural stress areas and large deformation tunnels with broken surrounding rocks. More specifically, the present invention relates to a primary support system and method for high ground stress and large deformation tunnels combined with release and resistance . Background technique [0002] With the continuous advancement of railway and highway construction, it is inevitable to build long tunnels in areas with harsh geological environments, high ground stress, and weak surrounding rocks. When tunnels are built in high ground stress broken surrounding rocks, the problem of large deformation of surrounding rocks often occurs. The Jiazhuqing Tunnel on the Nankun Railway, the Wushaoling Tunnel on the Lanzhou-Xinjiang Double Line, the Tauern Tunnel in Austria, and the Nakaya Tunnel in Ja...

AI Technical Summary

Problems solved by technology

[0003] Since the problem of large deformation has always been the primary problem that plagues technicians in the construction of tunnels with high ground stress and weak surrounding rocks, it often brings great difficulties to project construction and even causes major engineering accidents such as casualties

Due to the weak ability to resist deformation of the surrounding rock before the main body of the primary support is formed into a ring, and the deformation rate of the high ground stress fractured surrounding rock tunnel is relatively high after excavation, the primary support system in which the surrounding rock and the primary support body deform synchronously is often It is not worthwhile to destroy the primary supporting body before it forms a ring and plays a good role in controlling the deformation of the surrounding rock! This problem exists to varying degrees in the existing support systems with high rigidity based on "resistance", or support systems with a certain yield effect and "combination of yield and resistance".

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