Soft rock large-deformation tunnel support structure system and construction method thereof

Abstract

The invention relates to the field of tunnel engineering, in particular to a soft rock large-deformation tunnel support structure system and a construction method thereof. According to the soft rock large-deformation tunnel support structure system and the construction method thereof, double layers of elastic foam boards are arranged between surrounding rock and primary supports, thus enough surrounding rock deformation space is reserved so as to adapt to the requirement of soft rock tunnel large deformation, the problem of limit intrusion caused by too large surrounding rock deformation can be avoided, and surrounding rock pressure acting on a support structure can also be reduced effectively. The primary supports are reinforced, sprayed concrete spalling chipping, steel frame warp dislocation breakage, secondary lining cracking and other phenomena caused by too large stress on the support structure can be avoided by adopting the double-layer primary supports, and finally safety and reliability of the soft rock large-deformation tunnel support structure are ensured. Aiming at the characteristics that a soft rock large-deformation tunnel system is not obvious in anchor rod effect and waste time and labor, application of a system anchor rod in a soft rock large-deformation tunnel is canceled, the measures of reinforcement of a locking anchor pipe and steel frame longitudinal connection are provided, corresponding reasonable support parameters are given, and thus tunnel subsidence can be controlled better.

Description

[0001] 1. Technical Field: [0002] 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. [0003] 2. Background technology: [0004] Due to the lack of self-supporting capacity of soft rock, tunnel excavation often has the characteristics of large deformation, rapid deformation rate and long duration. If conventional construction methods are used, it is difficult to adapt to the large deformation requirements of soft rock tunnels, and it is easy to cause surroundings. Large area intrusion of the rock, spalling of shotcrete, distortion of the steel frame and even dislocation and cracking of the secondary lining, etc., and measures such as frequent removal and replacement of the steel frame, secondary excavation, and increase of the thickness of the lining are not only wasteful. Materials are also causing problems such as uncontrollable project cost, unpredictable c...

AI Technical Summary

Problems solved by technology

[0004] 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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