Tunnel excavation construction method of completely weathered granite shallow-buried water-rich layer milling excavator

Abstract

The invention provides a tunnel excavation construction method of a completely weathered granite shallow-buried water-rich layer milling excavator. The tunnel excavation construction method of the completely weathered granite shallow-buried water-rich layer milling excavator comprises the steps that guide pipes are adopted for pre-supporting, the guide pipes are directly pushed into guide holes through a pneumatic rock drill, and grouting is carried out on the guide pipes; a drainage device is driven on the face of a tunnel in the tunnel advancing direction, wherein the drainage device is arranged below the right portion of the face; part of waterflow is drained through well-points dewatering, the face water seepage phenomenon is weakened, the face is excavated through the milling excavator, sealing is carried out through face net hanging and concrete spraying in the construction process, and slumping and collapsing caused by face surrounding rock front face extrusion are effectively controlled through additional arrangement of the drainage device and other measures. The tunnel excavation construction method of the completely weathered granite shallow-buried water-rich layer milling excavator has the advantages of improving the drainage efficiency, improving the construction progress and the guaranteeing the stability of the tunnel face.

Description

technical field [0001] The invention relates to the technical field of tunnel excavation, in particular to a tunnel excavation construction method for a fully weathered granite shallow buried water-rich layer milling machine. Background technique [0002] The fully weathered granite water-rich layer has the characteristics of large settlement deformation, high soil water content, and poor self-stabilization ability. Due to the influence of groundwater, the geological conditions are complex, the excavation is prone to collapse, the safety risk is high, and the construction is difficult. [0003] In the process of excavating tunnels in the granite water-rich layer, a large amount of accumulated water will seep out of the tunnel face. In the existing technology, drainage pipes are used to directly drain the tunnel while digging, resulting in large over-excavation and large disturbance to the tunnel face. In addition, the water on the face of the tunnel is diverted to both sides...

AI Technical Summary

Problems solved by technology

[0002] The water-rich layer of fully weathered granite has the characteristics of large settlement deformation, high soil water content, and poor self-stabilization ability. Due to the influence of groundwater, the geological conditions are complex, the excavation is prone to collapse, the safety risk is high, and the construction is difficult.

[0003] In the process of excavating tunnels in the granite water-rich layer, a large amount of accumulated water will seep out of the tunnel face. In the existing technology, drainage pipes are used to directly drain the tunnel while digging, resulting in large over-excavation and large disturbance to the tunnel face. In addition, the water on the face of the tunnel is diverted to both sides with drainage pipes, the site is muddy, and the construction efficiency is low; in order to ensure the stability of the tunnel surrounding rock in the fully weathered granite water-rich layer, reduce the disturbance force of the ground during the excavation process, and improve the tunnel construction efficiency. Safety. The construction method of milling excavator combined with well point precipitation effectively solves the over-under-excavation and safety of excavator combined with manual excavation, reduces construction costs, improves construction progress, and ensures the stability of the tunnel face. In the process of using well point dewatering construction, an air compressor is connected to multiple drainage pipes. The inner suction of the drainage pipe farther away from the air compressor is smaller, but the drainage pipe farther away from the hollow pump is the closest to the face. And after installation, its internal water content is more, which reduces the efficiency of internal drainage of the face

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