Construction method for integral straight middle wall type double-arch tunnel

Abstract

The invention discloses a construction method for an integral straight middle wall type double-arch tunnel. The construction method comprises the following steps that a middle pilot tunnel is excavated according to design requirements, preliminary bracing of the middle pilot tunnel is carried out, the middle wall of a double-arch tunnel is constructed in the middle pilot tunnel, the top of the middle wall is of a Y-shaped structure, a middle wall top cavity is reserved between the top of the middle wall and the top wall of the middle pilot tunnel, a drainage system is arranged on the middle wall, backfill is carried out on the middle wall top cavity, a left hole and a right hole of the double-arch tunnel are excavated according to the design requirements, and pavement construction and tunnel mechanical and electrical installation engineering construction are respectively carried out on the left hole and the right hole after construction. Compared with an identical three-layer combined type straight middle wall structure, a three-layer combined type curved middle wall structure and a five-layer combined type curved middle wall structure, the construction method can effectively reduce the thickness of the middle wall, a structure is simple, construction is convenient, construction cost is reduced, the occupied area of a tunnel outer lead is reduced, and land resources are saved.

Description

technical field [0001] The invention relates to a tunnel construction technology, in particular to a construction method for an integral straight middle wall type double-arch tunnel. Background technique [0002] With the development of road construction, more and more roads gradually go into mountainous areas. The construction of highway tunnels has played an important role in reducing the incidence of traffic accidents, shortening the operating mileage, improving driving speed and comfort, effectively preventing various geological disasters caused by high filling and deep excavation of roadbeds, protecting the ecological environment, saving land, and promoting economic development. positive effect. Compared with separate tunnels, multi-arch tunnels have the advantages of smoother alignment and less land occupation, and more and more multi-arch tunnels are used in the construction of medium and short tunnels. However, the traditional multi-arch tunnel adopts an overall st...

AI Technical Summary

Problems solved by technology

However, the traditional multi-arch tunnel adopts an overall straight middle wall structure. Due to technological problems, there has always been a problem of water leakage at the top of the middle wall, which has caused many problems for operation and maintenance.

[0004] The Chinese patent "An Improved Composite Partition Wall Multi-Arch Tunnel Structure" (Application No.: 201020122453.9, Publication No.: CN201696056U) proposes: "In order to solve the problem of easy cracking at the initial support of conventional multi-arch tunnel structures and the fixing of the middle partition wall To solve the problem, the primary support and secondary lining of the conventional composite partition wall are separately arranged in a ring, and the joints between the primary support and the secondary lining and the intermediate partition wall are removed

"The specific structural form is that the straight middle wall is a flat roof structure, and the connection points between the initial support of the left and right main holes and the straight middle wall of this structure are not well stressed.

And the middle structure of this patent has as many as 3 layers, and its thickness is thicker than the single-layer straight middle wall structure of the patent of the present invention, with more construction procedures and longer construction period

Due to the thick middle structure of this patent, the excavation span of the entire multi-arch tunnel increases, the cost increases, and the area occupied by adjacent structures outside the tunnel increases

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