Tool change construction method of super large diameter mud-water-air balance shield in soft ground

Abstract

The invention discloses a tool-changing construction method for a super-large-diameter slurry air balanced shield machine in a soft soil stratum. The method comprises the steps of preparing front slurry for a cutter head of the shield machine, wherein the front slurry comprises water, slurry-making agents and tackifying agents; carrying out slurry circulation work on the soft soil stratum through the front slurry and forming a mud film structure on the surface of the soft soil stratum; adjusting the pressure in an operation bin of the shield machine to the set requirement according to the position of the shield machine for stabilizing the excavation face of the shield machine; and cooperatively adjusting the pressure of the operation bin, the pressure of a master bin and the pressure of a storage bin of the shield machine so that tool-changing personnel can enter the operation bin under pressure and complete the tool-changing work. According to the method, the front slurry for the cutter head of the shield machine comprises the water, the slurry-making agents and the tackifying agents and can form the mud film structure on the surface of the soft soil stratum for acting on the soil pressure and the water pressure of the excavation surface in a balanced mode.

Description

technical field [0001] The invention relates to the technical field of shield tunneling, in particular to a tool-changing construction method for an ultra-large-diameter mud-water-gas balance shield tunnel in a soft soil layer. Background technique [0002] Most of the existing shield tunnel tool change construction techniques focus on the replacement of shield hobs in rock TBM or sandy pebble formations. The ground where the shield is located must either have a certain degree of self-support, or adopt ground reinforcement to ensure the stability of the soil on the front of the shield. However, the mud-water-air balance shield (mixed shield) located in the saturated soft soil-sandy soil layer is usually buried at a large depth, the stability of the frontal soil is extremely poor, and the surface environment above the shield is complex, so it usually does not have full-section reinforcement. conditions of. [0003] How to ensure the frontal stability of shield tunneling is ...

AI Technical Summary

Problems solved by technology

Especially for shield tunnels with super large diameter (generally above 14m), the pressure difference between the top and bottom of the excavation surface is large, and it is more difficult to maintain the balance and stability of the front. Potentially endanger the life of the tool changing operator

There is currently no reliable method for the replacement of shield blades for ultra-large diameter shields in unreinforced saturated soft soil formations

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