Construction method for deep foundation pit with support piles and three-pipe high-pressure jet grouting piles

Abstract

The invention discloses a construction method for a deep foundation pit with support piles and three-pipe high-pressure jet grouting piles. According to the construction method, operation is conducted according to the design requirements, and after a cast-in-place pile is completed, a placing measurement hole position is determined; drilling is conducted through a drill machine, a high-pressure jet grouting pile machine is put in place and aligned with the hole position, slurrying is conducted through a stirring cylinder backstage, slurry supplied by a grouting pump, compressed air supplied by an air compressor and water supplied by a high-pressure pump are tried to be sprayed under the design parameters, debugging is conducted to the normal state, water supplied by the high-pressure pump is reduced to 2.0-3.0 MPa, pipes are sunken to the designed depth, and spraying and grouting are conducted; and after spraying construction is completed, machines and tools are transferred to the next hole position till all hole positions are completed. By the adoption of the construction method, decent and supply of underground water are controlled effectively, meanwhile the reinforcement and advance support functions on miscellaneous fill, silt, silty-fine sand and medium-coarse sand containing gravel are achieved, the stability of the edge walls of the foundation fit and the normal use and safety of surrounding buildings (structures) are guaranteed, the whole support stability is guaranteed, the cost investment is reduced, the benefits are increased, and the construction cost is reasonably distributed.

Description

technical field [0001] The invention relates to the technical field of building construction, in particular to a construction method for deep foundation pits of support piles and three-tube high-pressure rotary grouting piles. Background technique [0002] The high-pressure jet grouting (Jet Grouting) method is developed on the basis of the static pressure grouting (Grouting) method by applying high-pressure water jet cutting technology. [0003] In the late 1960s, when the Japanese N·I·T Company (Nakanishi Institute Technology Co,LTD) undertook the excavation project of the Osaka subway in Japan, it first used the freezing method and changed it to the static pressure grouting method due to the melting of frozen ice. Most of the grout overflowed from the junction of soil layers, which still could not achieve the purpose of foundation reinforcement and water stop. Mr. Nakanishi successfully applied the principle of hydraulic coal mining technology to static pressure grouting,...

AI Technical Summary

Problems solved by technology

[0008] Due to various reasons, the current equipment in our country is relatively old, the construction methods are backward and the work efficiency is low, which can no longer fully meet the domestic construction requirements, and it is even more difficult to enter the international market. Therefore, it is imperative to adopt advanced construction methods

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