Efficient improver for preventing mud cake

Abstract

The invention discloses an efficient improver for preventing mud cake. The efficient improver is prepared from 0.5 to 3.0% by mass of an anti-sticking additive, 4.0 to 10.0% by mass of an anionic surfactant, 1.0 to 4.0% by mass of a nonionic surfactant A, 1.0 to 4.0% by mass of a nonionic surfactant B and the balance water. The anti-sticking additive comprises one or two of sodium polyacrylate and sodium lignosulphonate. The efficient improver significantly reduces the adhesion of the dregs, reduces the adhesion of dregs to a cutter plate and blocking of the cutter plate, improves dreg plasticity and reduces energy consumption.

Description

technical field [0001] The invention belongs to the technical field of shield tunnel construction, and in particular relates to a high-efficiency improver for preventing mud cake. Background technique [0002] At present, the type of shield tunneling used in my country is mainly earth pressure balance shield tunneling, which is suitable for a wide range of geological conditions. The key to the success of earth pressure balance shield construction lies in effective muck improvement. The improvement of dregs is to inject the improver into the surface of the cutter head, the soil bin or the screw conveyor through the special device on the shield machine, and use the rotation of the cutter head, the stirring of the soil bin stirring device or the rotation of the screw conveyor to make the modifier and the muck The main purpose of mixing is to make the muck cut by the shield machine have good flow plasticity, suitable consistency, low water permeability and low frictional resist...

AI Technical Summary

Problems solved by technology

[0003] When shield tunneling in plastic and hard plastic clay strata, clay sandy soil stratum, mudstone, argillaceous siltstone, residual soil stratum whose parent rock is granite, fully weathered rock stratum and strongly weathered rock stratum, etc., the excavation surface The cohesive soil is crushed by the cutterhead cutter. When the muck is not improved properly, it is very easy to gradually form a mud cake on the cutterhead surface and the inner wall of the soil bin from the center of the cutterhead to the surroundings, blocking the opening of the cutterhead and aggravating the shield cutterhead. In addition, when the mud cake on the cutterhead rubs against the middle partition of the soil bin for a long time, the temperature of the middle partition and other positions will rise rapidly, causing the performance of the rubber seal in the rotary center to decline. Threat to the safety of shield construction

At present, the problem of "mud cake" has always been a major problem that has not been completely solved in the field of shield tunneling construction, and has always plagued construction workers in the industry.

While the research on the application of foaming agents is relatively advanced abroad, the application and research of foaming agents in my country started relatively late, and the technology is relatively backward. Cohesive soil formations prone to mudcake formation are less effective for improvement

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