Construction method for excavating support body in tunnel by crossing quicksand stratum

Abstract

The invention relates to a construction method for excavating a support body in a tunnel by crossing a quicksand stratum. The construction method comprises the following steps of arranging veneer plugboards on the outer side and the face of a steel frame of an arch, using advanced small guide pipes on the arch, and plugging boards on the outer sides of the small guide pipes; plugging boards on the face, arranging guide pipes at the periphery of core soil, welding steel bars, close to the face, on the advanced small guide pipes of the arch and the guide pipes of the core soil, ensuring that intervals of the steel bars are suitable to blocking of veneers, paving the plugboards on the surrounding rock face, preserving the core soil and taking other related measures; in the excavation engineering, dividing the tunnel face into an upper step, a middle step and a lower step, ensuring that the excavation and support of each part are staggered along the longitudinal direction of the tunnel and are carried out in parallel, and quickly constructing a support system structure. The construction method can effectively prevent the risk of quicksand in a sand layer, and the construction safety is high.

Description

technical field [0001] The invention relates to the field of tunnel construction, in particular to a construction method for excavating a support body for a tunnel passing through a quicksand stratum. Background technique [0002] In today's society, the development of the transportation system directly restricts the development of the country's comprehensive strength. There are a large number of quicksand formations in the complex terrain of our country. The quicksand formation is different from the characteristics of ordinary soft rock and soil. It has rheological properties, which makes it difficult to form tunnels in this formation, with poor stability and difficult support. At present, the construction progress of tunnels in this stratum is slow at home and abroad, the stability is poor, and the construction safety is low. [0003] In view of the above-mentioned defects, the author of the present invention has obtained this creation through long-term research and pract...

AI Technical Summary

Problems solved by technology

There are a large number of quicksand strata in the complex terrain of our country. The quicksand stratum is different from the characteristics of general soft rock and soil. It has rheological properties, which makes it difficult to form tunnels in this stratum, with poor stability and difficult support.

At present, the construction progress of tunnels in this stratum at home and abroad is slow, the stability is poor, and the construction safety is low.

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