Oversized variable cross section tunnel supporting structure

Abstract

The invention provides an oversized variable cross section tunnel supporting structure. Along the ring shape of a tunnel, the oversized variable cross section tunnel supporting structure comprises a top arch crown, a bottom inverted arch, side walls on the two sides and pilot tunnels on the outer sides of the side walls. The oversized variable cross section tunnel supporting structure comprises a secondary lining of an inner layer in the radial direction of the tunnel. Pilot tunnel primary supports are arranged on the outer sides of secondary linings of the side walls on the two sides, boot-shaped large wall feet are poured between the pilot tunnel primary supports and the secondary linings of the side walls on the two sides, primary supports are arranged on the secondary lining of the arch crown and the surface of the outer side of the secondary lining of the inverted arch in the radial direction of the tunnel, an inner layer primary support is arranged between the secondary lining of the arch crown and the primary supports, the primary support of the arch crown and the inner layer primary support are supported on the boot-shaped large wall feet, and the primary support of the inverted arch is supported on the pilot tunnel primary supports. The oversized variable cross section tunnel supporting structure solves the problem of insufficiency of the soft foundation bearing capacity better and provides a stable foundation for an upper structure.

Description

technical field [0001] The invention relates to the field of super large section tunnel construction, in particular to a super large variable section tunnel support structure. Background technique [0002] With the development of tunnel engineering, the support scheme of super-large cross-section tunnels has made great progress. However, in general, composite linings based on the new Austrian method are basically used, and bolts are used as initial support, and formwork concrete is used as secondary lining. The stiffness is different, for example, the length of the bolt, the thickness of the shotcrete, the change of the form of the steel frame, whether to add steel fibers, the change of the thickness of the formwork concrete, the change of the concrete label and so on. For such a large-span tunnel in this project, it is extremely rare, and there is little experience for reference, and it is located at the entrance of the mountain. Most of the rocks on the surface of the mou...

AI Technical Summary

Problems solved by technology

However, tunnels with such a large span in this project are extremely rare, and there is little experience to learn from, and they are located at the entrance of the tunnel. Most of the rocks on the surface of the mountain are extremely weathered, low in strength, and poor in stability. The foot of the rear arch sinks heavily, and the deformation of the vault cannot be controlled, which may even lead to cracking and instability of the lining, resulting in a collapse accident

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