A high-efficiency plugging film-forming shield mud material for emergency rescue

Abstract

The invention discloses a high-efficiency plugging film-forming shield mud material for emergency rescue, which comprises: 70%-80% of bentonite, 10-15% of polymer wrapping material, and 5-10% of colloidal strengthening agent , polymer dispersant 1‑3%, emulsifier 1‑3%. The invention combines the polymer wrapping material and bentonite in water to form elastic particles, so that the mud prepared by the high-efficiency plugging film-forming shield mud material for emergency rescue can effectively plug the formation pores and improve the stability of the excavation surface.

Description

technical field [0001] The invention relates to the technical field of shield tunneling construction. More specifically, the present invention relates to a high-efficiency plugging film-forming shield mud material for emergency rescue. Background technique [0002] During mud-water shield excavation, the shield mud plays two important roles: one is to rely on the mud pressure to form a mud film or seepage area on the excavation surface to improve the soil strength of the excavation surface, and at the same time, the mud pressure balances the excavation surface soil pressure and water pressure to achieve the purpose of keeping the excavation surface in a stable state during construction; second, mud is used as a transport medium to transport all the excavated soil and sand to the outside of the working well; among them, the maintenance of the excavation surface Stability is the key to ensure the safe and smooth progress of shield tunneling construction. [0003] Specificall...

AI Technical Summary

Problems solved by technology

The solid phase substances in conventional mud are all rigid particles with a fixed particle size. Therefore, the particle size and gradation of the solid phase substances must match the pore size of the formation in order to form an effective mud film on the excavation surface; when the particle size When the particle size is too large, the solid phase material cannot enter the pores in the formation to achieve a good plugging effect; when the particle size is too small, although the solid phase material can enter the formation pores, it will be affected by the formation water pressure and the pressure of the mud tank. is quickly washed away resulting in failure of the seal

Therefore, it is usually necessary to conduct model tests to select appropriate solid-phase materials in experiments based on geological reports. However, in actual construction, the formation conditions are complex and changeable, and geological reports cannot completely and accurately describe the formation conditions. , when the mud performance does not match the formation conditions, engineering quality and safety accidents are very likely to occur

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