Earth pressure balance type shield long-distance lake-crossing construction technology

Abstract

The invention provides an earth pressure balance type shield long-distance lake-crossing construction technology, which is characterized by comprising the following technological processes that: (1) before the lake crossing, equipment such as a shield tunneling machine cutterhead, a cutter, a grouting system, a sealing system, a thrust jack and a monitoring system are carefully inspected; (2) an earth pressure value is reasonably set, and the volume of excavated earth is strictly controlled; (3) the thrust speed is reduced, and the total thrust is controlled; (4) a shield posture is regulated, and the number of deviation correcting times and the deviation correcting quantity are reduced; (5) the slurry mixing ratio is optimized, and the grouting quantity and the grouting pressure are reasonably set; (6) water leakageat the shield tail is strictly prevented; (7) the construction quality is enhanced, and the tunnel self-waterproof capability is improved; (8) earth body improvement is performed; (9) secondary grouting supplementation is performed; (10) anti-drag slurry is injected; (11) after the shield crosses the lake bottom, the lake bottom in the interval influence range is subjected to radial grouting for reinforcement; and (12) the communication smoothness of the tunnel and the ground is ensured. The excessive lake bottom sedimentation is avoided, and the influence of accidents such as spewing or large-area collapse on the engineering safety and the environment safety is prevented.

Description

Technical field: [0001] The invention relates to the technical field of shield tunnel construction, in particular to the long-distance lake-crossing construction technology of an earth pressure balance type shield tunnel. Background technique: [0002] The long-distance construction of the shield machine through the lake, the sand layer of the excavation section is widely distributed, and the buried depth of the tunnel at the bottom of the lake is relatively shallow. Affected by factors such as subsidence or uplift sensitivity, the shield construction has a relatively high risk and lasts for a long time. Invention content: [0003] The purpose of this invention is to provide the long-distance construction technology of earth pressure balance shield tunneling through the lake, which reasonably selects the cutter head according to the lithology characteristics of the stratum, strictly controls the excavation speed, and correctly grasps the grouting material, grouting time and...

AI Technical Summary

Problems solved by technology

[0002] The shield machine is constructed across the lake for a long distance, and the sand layer of the excavation section is widely distributed. The tunnel at the bottom of the lake has a shallow buried depth. Affected by factors such as subsidence or uplift sensitivity, the shield construction has a greater risk and lasts for a long time