Supporting arch hidden digging top-down construction method

Abstract

The present invention relates to a one time supporting arch subsurface excavation reversed construction method. The steps of the method are as follows: at least a pair of upper guide hole and lower guide hole are respectively excavated in a top body and a bottom body corresponding with an underground structure design space; each pair of guide holes forms one span; then the hole wall is processed for primary supporting; the bottom of the lower guide hole is laid with a waterproof layer; the waterproof layer is casted with an underlayer frame structure soleplate; a slope stake and a middle upright post are constructed from the upper guide hole; the arc top of the upper guide hole is laid with the waterproof layer, and an arc top permanent structure is cast; then a midspan soil body is excavated between two upper guide holes by a subsurface excavation method to form a midspan upper guide hole and to be constructed as a midspan upper guide hole arc top permanent structure; the primary support at the bottom of the upper guide hole is chiseled and removed; a soil body is excavated downwards, and a structure lateral wall and a middle floor slab are cast; the rest partial solid between the primary support at the top of the lower guide hole and the middle floor slab is excavated, at the same time, the primary support at the top of the lower guide hole is chiseled and removed, the rest lateral wall structure is cast, and an even span structure soleplate is closed. The method has small construction risk, large construction field and fast construction speed, uses few big guide holes and solves the technical problems of the large amount of the guide hole, the small size of the guide hole, small construction space, multiple times of structure stress conversions, the repeated perturbation of wall rock, etc of the traditional subsurface excavation method.

Description

technical field [0001] The invention relates to the technical field of underground engineering construction, in particular to the underground excavation construction technology of large-scale underground construction engineering. Background technique [0002] The complex construction process and construction environment of underground engineering tunnels and many hidden safety hazards have always been the focus and difficulty of engineering construction. In order to avoid the impact on the above-ground traffic and underground pipelines, most of the current underground engineering tunnel construction adopts the underground excavation method. , these construction methods all have certain defects and limitations; the disadvantages of "side hole method", "middle hole method" and "eye method" are: the number of excavation divisions is large, the surrounding rock is repeatedly disturbed, and the structure is subjected to more force conversion; The main idea of ​​"PBA construction...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a safe, fast, and investment-saving construction method for underground excavation, which avoids many shortcomings of the traditional underground excavation method, and solves the difficulty in the construction of the small pilot hole of the traditional underground engineering underground excavation method, and the number of excavation divisions Many technical problems such as repeated disturbance of surrounding rock and many structural force transformations

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