Drag reducing mud and its preparation and use method

Abstract

The invention discloses drag reduction slurry, as well as preparation and use methods of same. The drag reduction slurry includes bentonite, an alkaline inorganic substance, polyacrylamide, and wateraccording to mass ratio of bentonite : alkaline inorganic substance : polyacrylamide : water = (290-295):(4-5):1:(645-655), wherein the alkaline inorganic substance is Na2CO3 and / or NaOH. The drag reduction slurry is excellent in water retention property, complete set performance, supporting and protecting performance and endurance, can be used for pipe jacking and shield tunneling and especiallyis suitable for high jacking force. During use, slurry injection frequency is reduced largely, and a slurry sleeve is effectively formed during the jacking process, thereby greatly reducing frictionresistance of outer wall of a pipeline and reducing jacking force during the jacking process, reducing cutter-head torque and working current, and reducing consumption of pipe jacking equipment.

Description

technical field [0001] The invention relates to drag-reducing mud and its preparation and use methods. Background technique [0002] In pipe jacking construction, drag reduction by grouting is a very important link, and it is the key to the success of pipe jacking. During the pipe jacking construction process, if the injected drag reducing mud can form a relatively complete drag reducing mud sleeve on the outer circumference of the pipeline, its drag reducing and supporting functions will receive unexpected results. The formation of an effective drag-reducing mud sleeve can greatly reduce the frictional resistance between the pipe wall and the soil layer, effectively reduce the jacking force, increase the length of one-way jacking, reduce the amount of relays, and also reduce the work The number of wells and receiving wells can effectively reduce the engineering cost. [0003] When the pipe jacking is carried out in the cohesive soil layer, because the soil layer itself is...

AI Technical Summary

Problems solved by technology

[0007] The technical problem solved by the present invention is to overcome the poor water retention, poor supporting performance, poor complete set performance and poor durability of the drag-reducing grout for pipe jacking in the prior art for the cohesive soil layer, which leads to the inability to Form a complete drag-reducing mud sleeve, and thus fail to provide effective support and drag-reducing effects, thereby providing a drag-reducing mud and its preparation and use method

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