Tunnel building method capable of penetrating through rockburst section

Abstract

The invention relates to a tunnel building method capable of penetrating through a rockburst section. The tunnel building method comprises the following steps: S1, arranging an anchor rod on a tunnelface to control rockburst of the tunnel face; S2, adopting presplitting blasting to explode a box cut along the contour line of the tunnel, wherein the tunnel longitudinal slotting length always exceeds the tunnel face, and keeping the surrounding rock of the core soil part; S3, after deslagging, arranging a section steel arch and a mesh reinforcement, constructing an energy-consuming anchor rod,carrying out pressure injection on large-damping flexible material for filling, and jetting steel fiber reinforced concrete on the surface; S4, arranging a cross anchor rod on the core soil along thetunnel cross section direction while carrying out preliminary bracing, and vertically hitting a glass fiber anchor rod in the core soil; and S5, according to the preset footage, carrying out blastingexcavation on the core soil step by step, wherein blastholes utilize axial hollow anchor rod holes to fill cartriges, and carrying out transverse slotting treatment on the core soil. With adoption ofthe tunnel building method, the rockburst occurring tendency can be controlled to certain degree, and safety during the tunnel construction process is ensured.

Description

Technical field [0001] The invention relates to the technical field of railway tunnel construction, in particular to a tunnel construction method for crossing a rockburst section. Background technique [0002] With the rapid development of the national economy, underground resource development and underground infrastructure construction are developing at an unprecedented speed. Among them, as the buried depth increases or is affected by tectonic stress, deep or ultra-deep tunnels will traverse complex strata. High in-situ stress area. Rock burst is a common geological hazard in high ground stress areas. High elastic strain energy is present in the deep rock mass in the high in-situ stress area. During the excavation process, energy accumulation will occur near the excavation surface under the influence of the far-field stress. When the accumulated strain energy exceeds the energy storage limit of the rock mass , The surplus energy was released suddenly, and part of the rock nea...

AI Technical Summary

Problems solved by technology

Although this method can release the tunnel stress in advance, it also changes the mechanical properties of the surrounding rock in the rockburst section, resulting in the indeterminate release of the surrounding rock stress, which aggravates the occurrence tendency and uncertainty of the rockburst; the Chinese invention patent CN107893673A discloses an anti-rockburst and large-deformation wing-type extrusion energy-absorbing bolts, including: the bolt body and the tray and nuts arranged at its tail, which can improve the effect of absorbing pressure and controlling disasters such as rockbursts or large deformations in deep underground engineering, but the The structure of the invention is too simple, and the absorbed energy is limited when a rockburst occurs, so it cannot really dissipate the rockburst energy and effectively control the rockburst; Chinese invention patent CN106368721A discloses a tunnel rockburst prevention support method and tunnel rockburst prevention The support system includes surrounding rock, shotcrete layer and multiple prestressed energy-releasing bolts. The shotcrete layer is provided with multiple grooves arranged at intervals, which can prevent or reduce the occurrence of rockburst to a certain extent. trend, but this method will inevitably aggravate the stress concentration of the initial support sprayed concrete, and increase the possibility of rockburst on the other hand.

Furthermore, the above inventions all focus on weakening and controlling the occurrence of rockbursts, and cannot protect construction personnel and equipment when rockbursts occur, and reduce the impact of rockbursts.

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