Support structure system and construction method of large cross-section deep shaft in rocky strata

Abstract

The invention relates to a supporting structure system of a rock stratum large-section deep vertical shaft and a construction method of the supporting structure system. If the large-section deep vertical shaft is supported only through steel frame anchor and shotcrete supporting, stability or deformation of the side wall of the vertical shaft can hardly be effectively controlled. The supporting structure system comprises primary supporting shotcrete, wherein a primary supporting grid steel frame is preset in the primary supporting shotcrete. Multiple layers of transverse horizontal steel supports are arranged in the space, inside the primary supporting shotcrete, of the vertical shaft from top to bottom, wherein each steel frame comprises inclined steel braces located at the four corners and a straight steel brace located in the middle, the ends of the steel frames are all fixed to a steel surrounding purlin which is arranged on the inner wall of the primary supporting shotcrete in a surrounding mode, the periphery of the steel surrounding purlin is fixed to a primary supporting profile steel frame embedded in the primary supporting shotcrete, primary supporting anchor rods are welded to both the primary supporting grid steel frame and the primary supporting profile steel frame, and the other ends of the primary supporting anchor rods are hit into surrounding rock. According to the supporting structure system and the construction method, flexible supporting and rigid supporting are reasonably combined, a conventional supporting method is not changed, construction is convenient, investment is saved, and overall stability of a vertical shaft foundation pit is enhanced.

Description

technical field [0001] The invention belongs to the technical field of tunnel construction, and in particular relates to a support structure system and a construction method for a large-section deep shaft in a rock formation. Background technique [0002] The 21st century is a period of rapid development of underground engineering, especially in recent years, the construction of my country's subway engineering is in full swing. The wide application of rock tunnel boring machines in subway engineering puts forward higher requirements for the size and depth of their working shafts; in addition, large cross-section deep shafts are also widely used in underground engineering construction in other fields. For such a large excavation section and excavation depth, whether to consider the support type according to the general shaft or to implement the enclosure structure according to the deep foundation pit is a difficult problem in front of the design; The commonly used support me...

AI Technical Summary

Problems solved by technology

For such a large excavation section and excavation depth, whether to consider the support type according to the general shaft or to implement the enclosure structure according to the deep foundation pit is a difficult problem in front of the design; The commonly used support method is steel frame anchor shotcrete support, but for shafts with large sections, if only steel frame anchor shotcrete support is used, it is difficult to effectively control the stability and deformation of the side wall of the shaft, posing a safety risk Larger; if the deep foundation pit is considered, the commonly used support type of "cast-in-situ pile + internal support" will have a great impact on project investment and construction progress, resulting in a lot of project waste

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