tunnel shaft construction method

Abstract

A tunnel shaft construction method relates to a tunnel shaft construction method. The utility model is mainly designed to solve the problems of slow construction speed and the like in the existing tunnel shaft construction method. Excavate the topsoil section of the wellhead of the shaft and make a locking ring. Backfill the well circle wall with concrete to the wellhead elevation. Construct the wellhead reinforcement section; excavate the well body by drilling and blasting method, and carry out primary support; after the wellbore excavation and primary support are completed, carry out secondary lining and wall seat construction. Drill the blast hole well, and then carry out blasting, rock grasping and lifting work. Finally, the primary support of the shaft is carried out, and the concrete is sprayed. After the shaft excavation and the initial support are completed, the secondary lining and wall seat construction are carried out. After the excavation of the shaft is completed, the sprayed concrete construction shall be carried out after the vertical drainage pipe is set up at the place where the water leaks on the surface of the surrounding rock of the shaft for centralized drainage. After spraying the concrete, lay a soft permeable pipe on the surface of the sprayed concrete to drain the water into the central drainage ditch of the main tunnel. The advantage is that the construction speed is fast.

Description

Technical field: [0001] The invention relates to a tunnel shaft construction method. Background technique: [0002] During the construction of the existing extra-long tunnel, in order to shorten the construction period, a shaft should be set in the middle section of the tunnel to increase the working surface. The existing tunnel shaft construction method has the problems of slow construction speed and too long single cycle time of each process. Generally, the cycle time of mechanical construction is between 19-22 hours, which affects the construction progress. In addition, the waterproof and drainage measures are poor, and the safety and quality in the later stage cannot be well guaranteed. According to incomplete statistics, 70% of every 100 shafts in the current shaft project are maintained in the later stage due to drainage leakage and frost heaving in alpine regions. However, the later maintenance is particularly difficult, which greatly increases the construction cost....

AI Technical Summary

Problems solved by technology

The existing tunnel shaft construction method has the problems of slow construction speed and too long single cycle time of each process. Generally, the cycle time of mechanical construction is between 19-22 hours, which affects the construction progress

In addition, the waterproof and drainage measures are poor, and the safety and quality in the later stage cannot be well guaranteed

According to incomplete statistics, 70% of every 100 shafts in the current shaft project are maintained in the later period due to drainage leakage and frost heaving in the alpine region. However, the later maintenance is particularly difficult, which greatly increases the construction cost