Large-section and small clear spacing dark excavation construction method through combined supporting of MJS construction method and pipe curtain method

Abstract

The invention discloses a large-section and small clear spacing dark excavation construction method through combined supporting of an MJS construction method and a pipe curtain method. The large-section and small clear spacing dark excavation construction method comprises the following steps that according to requirements and the actual situation of site geology, relevant parameters of steel pipes, position arrangement of the steel pipes and relevant parameters of MJS piles are designed; working vertical shafts are arranged at the two ends of a planned large-section and small clear spacing tunnel; the steel pipes are horizontally jacked into along the outer contour of the planned large-section and small clear spacing tunnel, so that a pipe curtain is formed; the interior of the pipe curtain is densely filled with concrete; the MJS piles are constructed along the periphery of the pipe curtain; and excavation is conducted, and construction of the inner structure of the planned large-section and small clear spacing tunnel is completed. The interior of the pipe curtain is densely filled with concrete, so that pipe curtain enclosure with the sufficient rigidity is formed; and the MJS piles are constructed around the periphery of the pipe curtain, so that water stop between gaps of the steel pipes is achieved, safety of excavation of the planned large-section and small clear spacingtunnel is ensured fundamentally, and risks can be controlled.

Description

Technical field [0001] The invention relates to the technical field of underground engineering, in particular to an undercut construction method for combined support of a large section and a small clear distance by an MJS construction method and a pipe-screen method. Background technique [0002] The rational development of underground space is an important manifestation of the scientific utilization of urban underground space resources and adaptation to urban modernization and sustainable development. [0003] At present, when passing through sensitive structures under relatively weak geological conditions, or when building underground structures such as tunnels or passages near the foundations of important structures, freezing methods, rectangular pipe jacking methods, or some combined support methods are often used. . [0004] If the proposed tunnel needs to pass under an existing subway line, especially a subway shield tunnel, when the clear distance between the underpass tunnel...

AI Technical Summary

Problems solved by technology

When the large-section rectangular pipe jacking method passes through the existing subway shield tunnel with a small clear distance, due to the limited size of the current large-section rectangular pipe jacking equipment, the large-section rectangular pipe jacking machine equipment needs to be specially made, and at the same time, the large-section rectangular pipe jacking machine is adaptable to the formation Poor, if it encounters local hard formations, or uneven soft and hard formations, the construction will be difficult, the equipment will have poor versatility, the usable places will be limited, and the economy will be poor.

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