A soft rock large deformation tunnel support structure system and its construction method

Abstract

The invention relates to the field of tunnel engineering, in particular to a soft rock large deformation tunnel supporting structure system and a construction method thereof. By setting double-layer elastic foam boards between the surrounding rock and the primary support, enough surrounding rock deformation space is reserved to meet the large deformation requirements of soft rock tunnels, which can not only avoid the encroachment problem caused by excessive deformation of the surrounding rock, Moreover, it can effectively reduce the surrounding rock pressure acting on the support structure; the initial support is strengthened, and the use of double-layer initial support can avoid spalling and falling of shotcrete and twisting and breaking of steel frames caused by excessive force on the support structure , secondary lining cracking and other phenomena, and finally ensure the safety and reliability of the soft rock large deformation tunnel support structure; in view of the characteristics of soft rock large deformation tunnel system anchor bolt effect is not obvious and time-consuming and labor-intensive, cancel the system anchor bolt in soft rock large deformation tunnel Based on the application in the tunnel, the measure of strengthening the longitudinal connection between the anchor pipe and the steel frame is proposed, and the corresponding reasonable support parameters are given to better control the tunnel settlement.

Description

1. Technical field: [0001] The invention relates to the field of tunnel engineering, in particular to a soft rock large deformation tunnel supporting structure system and a construction method thereof. 2. Background technology: [0002] Due to the lack of self-supporting capacity of soft rock, tunnel excavation often has the characteristics of large deformation, fast deformation rate and long duration. Large-scale encroachment of rock, spalling and falling of shotcrete, twisting and deformation of steel frame or even misalignment, and cracking of secondary lining, etc., and then measures such as frequent removal and replacement of steel frame, secondary excavation, and increase of lining thickness have to be taken, which not only wastes Materials, but also lead to uncontrollable project cost, unpredictable construction period and construction safety can not be guaranteed. It can be said that the problem of large deformation of soft rock tunnels is a worldwide problem in the...

AI Technical Summary

Problems solved by technology

[0002] Due to the lack of self-supporting capacity of soft rock, tunnel excavation often has the characteristics of large deformation, fast deformation rate and long duration. Large-scale encroachment of rock, spalling and falling of shotcrete, twisting and deformation of steel frame or even misalignment, and cracking of secondary lining, etc., and then measures such as frequent removal and replacement of steel frame, secondary excavation, and increase of lining thickness have to be taken, which not only wastes materials, which cause problems such as uncontrollable project cost, unpredictable construction period and unguaranteed construction safety.

It can be said that the problem of large deformation of soft rock tunnels is a worldwide problem in the field of tunnel engineering and has not been well resolved. It is urgent to invent a support structure system and its construction method that are suitable for large deformation requirements of soft rock tunnels

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