Pressure gas balanced tunneling method for upper-soft lower-hard stratum and full-section hard rock of earth pressure balance shield

Abstract

The invention discloses an earth pressure balance shield tunneling method with pressure-air balance for upper soft and lower hard rock and full-section hard rock. Excavation: Earth pressure balance shield machine is used for shield tunneling construction; during shield tunneling construction, air is injected into the soil bin through the air pipe to keep the internal pressure of the soil bin stable, and the soil is discharged outward through the screw excavator to make the soil The distance between the upper surface of the muck in the warehouse and the top of the excavation opening is always 20cm to 40cm; 3. Shield segment assembly construction: During the shield excavation construction process in step 2, the shield tunneling is carried out according to the conventional segment assembly lining construction process. Segment assembly construction to obtain assembled segment rings. The invention is reasonable in design, easy to operate and good in use effect, can effectively solve various problems existing in the tunneling process of shield tunneling in stratums with upper softness and lower hardness and full-section hard rock, and can effectively reduce construction costs while increasing the tunneling speed.

Description

technical field [0001] The invention belongs to the technical field of subway shield construction, and in particular relates to an earth pressure balance shield tunneling method for tunneling with pressure-air balance for soft rock at the top and hard rock at the bottom. Background technique [0002] Full-section hard rock excavation is a difficult problem often encountered in the construction of shield tunnels in subway intervals. When excavating top-soft and bottom-hard and full-section hard rock earth pressure balance shield tunneling, high temperature in the warehouse, rapid tool wear, gushing, and injection often occur. Segment floating and other problems caused by poor slurry quality lead to an increase in the construction cost of the section, and the construction period and project quality cannot be effectively guaranteed. With the large-scale subway construction in my country, there are more and more excavations in the upper soft and lower hard strata and the full-se...

AI Technical Summary

Problems solved by technology

At present, most construction units in China adopt the earth pressure balance method for excavation in the upper soft and lower hard strata, while in the full-section hard rock stratum, they use empty chamber no-pressure excavation or low earth pressure excavation construction. During the excavation process, high temperature in the chamber, Rapid tool wear, gushing, poor quality of synchronous grouting, etc.

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