Construction method for drainage cement mixing pile

Abstract

The invention discloses a construction method for a drainage cement mixing pile. According to the principle that the permeation coefficient of high liquid limit clay can be increased by doping low-dosage cement or other modifiers (such as lime) into the high liquid limit clay, the stirring diameter is adjusted by changing the rotating direction of a blade in combination with a novel nail-shaped cement bidirectional stirring pile machine tool emerging currently, and low-dosage (the dosing ratio is generally less than 5 percent) cement or other modifiers (such as lime) which can be used for increasing the clay permeation coefficient is sunk and sprayed for the first time to form a large-diameter drainage body. In a rising process, high-dosage (the dosing ratio is generally not less than 5 percent) cement or other curing agents which can be used for enhancing the strength of a soil body is sprayed in a rising process, and reverse rotation is performed to form a small-diameter central pile body. The large-diameter pile body is mainly used for increasing the permeation coefficient of the soil body and releasing water pressure from apertures. The small-diameter pile body is mainly used for enhancing the foundation bearing capacity. The problems of slow release of water pressure from the apertures of the soil body and low strength in a high liquid limit clay area, and complex process and high manufacturing cost in other foundation treatment methods are solved.

Description

technical field [0001] The invention relates to a construction method of a novel drainage cement-soil mixing pile, which is suitable for areas with high liquid limit soft clay and belongs to the technical field of civil engineering. Background technique [0002] High liquid limit soft clay has the characteristics of high water content, low permeability coefficient, high compressibility, and low bearing capacity. Therefore, it is necessary to take drainage measures for the foundation or deep reinforcement before other follow-up construction can be carried out. Most of them involve drainage preloading and composite foundation. In the engineering practice of highway foundation treatment, cement-soil mixing pile is a common form of composite foundation. In recent years, some innovations have appeared in the composite foundation technology of traditional cement-soil mixing piles. For example, Dong Ping of Nanjing University proposed to insert small-diameter prefabricated concret...

AI Technical Summary

Problems solved by technology

[0005] Technical problem: In order to solve the shortcomings of the current cement-soil mixing piles in high liquid limit clay areas that do not have drainage function, and other foundation treatment methods have long construction period, complicated process and high cost, the invention provides a new type of drainage cement-soil mixing pile. Construction method

Images