Method for controlling deformation in zero-distance tunneling of new tunnel under existing subway construction

Abstract

The invention discloses a method for controlling deformation in zero-distance tunneling of new tunnel under existing subway construction. The method is characterized in that: lifting jacks are arranged between the base plate of the existing subway construction and the side wall of the newly-built tunnel to make full use of time-space effect of tunnel excavation and apply lifting force in time; consolidation settlement of the soil body of the foundation of the newly-built tunnel is performed in advance so as to reduce late soil body settlement and achieve the aim of controlling deformation of the subway construction; and meanwhile, the deformation of the existing subway construction is adjusted and controlled in real time by using remote monitoring and the lifting jacks to ensure the safety of the construction and operation of an existing subway. On the basis of the conventional shallow excavation method construction, the method comprises the following steps of: firstly, grouting and strengthening the soil body within certain range of both sides and bottoms of cross sections for the tunnel excavation to improve bearing capacity of the soil body so as to arrange the lifting jacks ata plurality of positions of the initial liner side wall of the newly-built tunnel corresponding to the upper subway construction; and secondly, arranging profile steel top beams between the lifting jacks and the base plate of the existing subway construction to make the lifting force of the lifting jacks uniformly act on the existing subway construction.

Description

technical field [0001] The invention relates to the field of underground engineering, in particular to a method for controlling deformation of a new tunnel passing under a subway structure at zero distance. Background technique [0002] With the increasing network and scale of urban rail transit and the rapid development of rail transit and municipal facilities, the spatial intersection between rail transit, municipal tunnels (such as power and thermal tunnels) and existing operating subways is inevitable. Restrictions in the environment or facilities have to force the two to adopt close or close crossing methods. With the development of rail transit networks, the capacity of rail transit is constantly increasing. In order to ensure safe operation, the structure and track Deformation presents increasingly stringent requirements. If the design or construction of the short-distance crossing subway project is not handled properly, the durability of the subway structure will be...

AI Technical Summary

Problems solved by technology

[0004] However, when the new tunnel is used to pass under the operating rail transit line in a short distance by using the shallow buried excavation method or other construction methods, the stress release of the ground caused by the excavation and the secondary settlement caused by the loss of water in the ground will cause damage to the surface buildings and underground structures. Normal use or its structural safety is affected. As far as the subway structure is concerned, it will affect the stability and safety of subway train operation in serious cases

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