Full-rammed type construction method for specially-shaped multi-head enlarged toe pile

Abstract

The invention discloses a full-rammed type construction method for a specially-shaped multi-head enlarged toe pile. The full-rammed type construction method comprises the following steps: a, ramming an immersed tube at a pile position to form a pile hole; b, upwards pulling an inner sleeve, filling concrete needed for forming a pile body in an outer sleeve, performing forced ramming, synchronouslypulling the outer sleeve upwards to perform primary base expanding; c, after primary base expanding is performed, adopting a piling machine to forcibly ram concrete again to perform secondary base expanding; d, pulling the inner sleeve after secondary base expanding construction is completed, filling concrete into the outer sleeve, ramming the immersed tube, synchronously upwards pulling the outer sleeve to extrude concrete positioned in the outer sleeve, thereby forming a pile body; e, after the pile body is constructed to a preset position, performing forced ramming again, synchronously upwards pulling the outer sleeve to radically expand the pile body; f, after an expanded head of the pile body is formed, filling concrete, ramming the immersed tube, synchronously upwards pulling the outer sleeve to extrude concrete, thereby forming the pile body; and g, inserting the pile body into a reinforcement cage.

Description

technical field [0001] The invention relates to a pile body construction method of a building foundation, in particular to a construction method of a fully rammed special-shaped multi-head bottom expansion pile. Background technique [0002] The single pile bearing capacity of the pile body of the building foundation is mainly determined by the end resistance of the pile bottom and the frictional resistance of the pile body. No matter increasing one or both of the two forces, the single pile bearing capacity can be improved. Chinese patent document CN2023233935U discloses a cast-in-situ concrete large-diameter hollow five-star pile and its special construction equipment. The frictional resistance of the pile body is improved by reducing the volume of the pile body and increasing the surface area of ​​the pile body. Cylindrical hollow casing with five-star cross-section, and vibratory hammer equipment for immersed tubes. Although using this set of equipment and the technolog...

AI Technical Summary

Problems solved by technology

Although this patent document discloses a relatively wide prefabricated reinforced concrete pile point, it is prefabricated, and the pullout resistance of the pile body is insufficient after being driven into the soil. In addition, a Y-shaped plastic sleeve with threads is arranged inside the pile body The pipe is connected with the outer sleeve so that the injected concrete can be better combined with the Y-shaped plastic sleeve, so as to be integrated with the prefabricated reinforced concrete pile tip at the bottom to improve the pullout resistance of the pile body. However, this patent In the literature, the cement soil on the outside of the pile body finally forms a cylindrical pile body, so the friction resistance of the pile body has not been improved.

In addition, there are some defects in the molds and equipment used to make the special-shaped piles for the above two patent documents. For example, the mold used to make the five-star shaped pile body disclosed in the patent document CN2023233935U is a uniform five-star-shaped columnar sleeve in cross section. Tube, this kind of casing needs another inner casing that also has a five-star shape and its structure is matched with it. Due to the relative rotation and side collision between the pipes, the damage to the casing is relatively large

The special-shaped pile disclosed in the Chinese patent document CN103485334B is too complicated for making special-shaped piles with expanded bottoms, and the manufacturing steps are relatively cumbersome, and the final pile resistance and pile bearing capacity are not good enough

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