Low-permeability sludge claypan ultra-vacuum dual-pipe unwatering well and construction technology

Abstract

The invention relates to the technical field of dewatering of underground construction and particularly to a low-permeability sludge claypan ultra-vacuum dual-pipe unwatering well and a construction technology. The low-permeability sludge claypan ultra-vacuum dual-pipe unwatering well is characterized in that a well body structure adopts a steel pipe comprising an outer pipe and an inner pipe. The outer pipe comprises sealed pipes and a filter pipe, the upper and lower segments of pipe walls of the outer pipe are the airtight sealed pipes, the middle segment of the pipe wall of the outer pipe is the filter pipe with filter holes, and both the pipe top and the pipe bottom of the outer pipe are sealed. A pipe wall of the inner pipe is sealed, and the pipe top and the pipe bottom of the inner pipe are opened. The top part of a vacuum cavity between the inner pipe and the outer pipe is connected with a vacuum pump through a pipeline. A submerged pump is installed in an inner cavity of the inner pipe and a submerged pump connection pipeline serves as a water outlet of the inner cavity. According to the invention, the vacuum effect is utilized, the inner cavity and an outer cavity are arranged in a well casing structure, the outer cavity is an independent vacuum interlayer, a relatively high vacuum degree is continuously kept, the catchment efficiency of the dewatering well is high, and the radius of influence of a single well is large; the submerged pump is installed in the inner cavity, vacuumizing is conducted on the outer cavity, mutual influence of the inner cavity and the outer cavity is avoided, and the process is simple; and when large-area precipitation occurs, the number of configured wells is greatly reduced, and the pre-precipitation time is short.

Description

[technical field] [0001] The invention relates to the technical field of underground engineering dewatering, in particular to an ultra-vacuum double-pipe dewatering well in low-permeability muddy clay layer and its construction technology. [Background technique] [0002] With the rapid development of my country's economy, the subway industry is changing with each passing day. In my country's 12th Five-Year Plan, the subway is gradually moving from large cities to medium-sized cities. The construction environment of subways is becoming more and more complex, and subway stations have been constructed in various strata. Before the excavation of the deep foundation pit of the subway station, the foundation pit precipitation is usually used to consolidate the soil, so as to improve the strength of the soil in the pit and reduce the deformation of the pit bottom and the surrounding structure. In the dewatering construction, there are currently many methods used in China: self-seep...

AI Technical Summary

Problems solved by technology

However, in engineering practice, it is highlighted that the sealing performance is poor, the vacuum degree is insufficient, and the drying effect is not good.

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