Foam agent for earth pressure balance shield dregs improvement and preparation method thereof

Abstract

The invention provides a foaming agent for improvement of slag oil of a soil pressure balance shield and a preparation method thereof. The foaming agent for the improvement of the slag oil of the soilpressure balance shield is prepared from the following components in percentage by weight: 4% to 8% of alpha-alkenyl sodium sulfonate, 8% to 12% of lauryl sodium sulfate, 3% to 5% of alkylphenol polyoxyethylene, 0.05% to 0.2% of xanthan gum, 1% to 4% of coconut oil fatty acid diethanolamide, 1% to 3% of sodium gluconate, 0.5% to 2% of polyethylene oxide, 1% to 2% of polyaspartic acid, and the balance of water. The foaming agent has the advantages that by adopting the alpha-alkenyl sodium sulfonate, the lauryl sodium sulfate and the alkylphenol polyoxyethylene to prepare the foaming agent, thefoaming ability is enhanced under the compounding and cooperation function of the alpha-alkenyl sodium sulfonate, the lauryl sodium sulfate and the alkylphenol polyoxyethylene; the foaming time is greater than 30 times; by adopting the coconut oil fatty acid diethanolamide to enhance the surface action force of the air foam through cooperation, the stability of the foam under the high-speed shearing function of a knife disc is improved; the pressure fluctuation of a soil bin is reduced; the stability of the excavated surface of the shield is improved.

Description

technical field [0001] The invention belongs to the field of shield construction materials, in particular to a foaming agent for soil improvement of earth pressure balance shield tunnel and a preparation method thereof. Background technique [0002] With the rapid development of cities in our country, the population has increased sharply, and the pressure on transportation has increased sharply. Subway and tunnels have entered a period of rapid construction and development. In underground transportation construction, the earth pressure balance shield machine has become the most widely used type of shield machine because of its economic advantages. In the construction of earth pressure balance shield, the important factor to determine the tunneling efficiency is the improvement effect of muck. The muck improvement is to inject foam into the excavation surface or the soil cabin through the special equipment on the shield machine, and adjust the cut soil to a "plastic flow sta...

AI Technical Summary

Problems solved by technology

In recent years, a large number of domestic foam agents for soil improvement have been put on the market, and the market share has gradually expanded. However, the existing products still have many shortcomings. Obviously; the prepared foam has poor stability and short half-life, which leads to the phenomenon of easy accumulation of dregs in the excavation process, which affects the excavation efficiency; the prepared foam diameter distribution range is too large, and the improvement effect on silt and fine sand layer geological dregs is poor. Complex geological shield construction still cannot get rid of the dependence on imported shield foam agent

[0003] After improvement, the foaming multiple and half-life of most domestic foaming agent products have been improved, but the improvement effect is not obvious enough, and the effect is not up to expectations. During construction, there is an essential difference between the high-speed shear stability of the foam at the cutter head and the static stability. The foam is subjected to high-speed shear and soil pressure of the cutter head in the soil cabin, and the high-speed shear stability is easily deteriorated rapidly. As a result, the pressure of the soil tank fluctuates significantly, and it is easy to cause the instability of the excavation surface and the spewing phenomenon at the mouth of the screw conveyor, thus affecting the excavation of the shield machine

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