Limb double-layer drill structure

Abstract

The invention relates to a double-layer drill bit structure for limbs, comprising a rotating shaft, a tapered drill bit is arranged at the lower end of the rotating shaft, and the tapered drill bit includes a cone tip and a helical piece arranged on the cone tip, and is characterized in that: the rotating shaft The lower end of the drill assembly is provided with a lower drill assembly, and an upper drill assembly is arranged above the lower drill assembly. The outer diameter of the upper drill assembly is larger than that of the lower drill assembly. Assemblies, the screw assembly includes a radially arranged cone rod, and the outside of the cone rod is provided with a helical blade; the upper drill bit assembly is an assembled structure of two symmetrical halves, and the upper drill bit assembly includes a shaft collar assembled from two petals 1. A front frame, a rear frame and a screwed assembly respectively fixed on the shaft hoop assembled by the two petals. The invention is suitable for projects in which the diameter of the upper stirring soil pile is larger than that of the lower stirring soil pile.

Description

technical field [0001] The invention relates to the construction field, in particular to a four-limb double-layer drill bit structure used for cement-soil mixing pile construction. Background technique [0002] Cement-soil mixing pile is a method for reinforcing saturated soft clay foundations. It uses cement as a curing agent, and the soft soil and curing agent are forced to be stirred deep in the foundation through a cement-soil mixing pile machine. A series of physical and chemical reactions produced during the process make the soft soil harden into a high-quality foundation with integrity, water stability and certain strength, so as to achieve the purpose of strengthening the foundation. The reinforcement depth usually exceeds 5m, the dry reinforcement depth should not exceed 15m, and the wet reinforcement depth should not exceed 20m. The cement slurry pressed into the soft soil and the surrounding soft soil are forcibly mixed with the rotating stirring blades to form a...

AI Technical Summary

Problems solved by technology

In order to improve the quality of piles, construction units generally adopt the method of increasing the mixing time to improve the uniformity of mixing. However, although this construction method improves the quality of piles to a certain extent, its construction efficiency is significantly reduced. up

Therefore, it is not a proven solution

In addition, the existing equipment cannot be used in engineering reinforcement where the pile diameter of the upper mixed soil pile is larger than that of the lower mixed soil pile.

Images