Construction method and anchoring device for foundation pit composite support technology

Abstract

The invention discloses a construction method and anchoring device for a foundation pit composite support technology. The anchoring device comprises spiral anchor heads, connecting heads, an anchor rod, anchor cables and anchor devices. The front ends of the connecting rods are connected with the rear ends of the spiral anchor heads in a threaded mode, and the rear ends of the connecting heads areconnected with the anchor rod through a mortise and tenon joint structure; the front ends of the anchor cables penetrate through the anchor rod and the connecting heads to be connected with the anchor devices, the anchor devices are placed in inner cavities of the spiral anchor heads, and the diameters of inner holes of the connecting heads are smaller than the outer diameters of the anchor devices. According to the construction method and the anchoring device for the foundation pit composite support technology, an anchor cable spiral anchoring device is combined with a steel beam and an ejector anchor support to form a composite support system, load is dispersed into deep-layer soil bodies by foundation pit side wall soil pressure according to the transferring path of an ejector anchor surface layer, the steel beam, the anchor cables, the spiral anchor heads, and the purpose of stabilizing a foundation pit is achieved. According to the construction method and anchoring device for thefoundation pit composite support technology, the spiral anchor heads are taken as anchoring bodies, grouting is not needed, after spiraling, bearing force can be provided, and after recovering, the influence on the space nearby underground is small, the working period can be effectively saved, and reliability is high; and according to the construction method and anchoring device for the foundation pit composite support technology, pile forming is not needed during construction, excavation can be directly conducted, the working period is shortened, requirements for construction machinery are reduced, and the cost is saved.

Description

technical field [0001] The invention relates to a foundation pit support technology, in particular to a construction method and an anchoring device of the foundation pit composite support technology. Background technique [0002] At present, both soil nail wall support and pile-anchor combined support technology have been widely used in foundation pit support engineering. Because it is difficult to control the deformation of the structure and the settlement of surrounding buildings, the single soil nail wall support is only suitable for non-soft soil foundation pits with shallow excavation depth, above the groundwater level or after precipitation and which can achieve temporary self-stabilization. The pile-anchor combination support technology has the advantages of strong ability to control soil deformation, is not affected by groundwater, and occupies a small space. Some computational theoretical research lags behind engineering practice, and the overall design tends to be...

AI Technical Summary

Problems solved by technology

Because it is difficult to control the deformation of the structure and the settlement of surrounding buildings, the single soil nail wall support is only suitable for non-soft soil foundation pits with shallow excavation depth, above the groundwater level or after precipitation, and can achieve temporary self-stabilization

The pile-anchor combination support technology has the advantages of strong ability to control soil deformation, is not affected by groundwater, and occupies a small space. The theoretical research of calculation lags behind the engineering practice, and the overall design tends to be conservative, so there is a problem of high engineering cost

In addition, soil nails and anchor rods (cables) generally need to be cured for more than 7 days to form anchors after grouting. During this period, reliable anchoring force cannot be provided, so the foundation pit cannot be excavated continuously, resulting in extended construction period

Furthermore, the anchoring body has a relatively long length and generally cannot be recycled, which will also become an obstacle to the development of the surrounding underground space in the future

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