Construction method for a tunnel with any cross section in a hard rock stratum

Abstract

The invention provides a construction method for a tunnel with any cross section in a hard rock stratum. The construction method comprises the following steps that 1, the position of a vertical groove (1) and the positions of a plurality of expansion cracking holes (2) are calibrated on a tunnel face (3) of the tunnel; 2, the vertical groove (1) is dug in the tunnel face (3) according to the calibrated position of the vertical groove (1), and the expansion crack holes (2) are drilled in the tunnel face (3) according to the calibrated positions of the expansion crack holes (2); and 3, expansion cracking operation is carried out on the expansion cracking holes (2), so that the rock between the vertical groove (1) and the expansion cracking holes (2) is separated from the tunnel face (3). According to the construction method for the tunnel with the any section in the hard rock stratum, vertical groove digging and hydraulic hole expansion are combined, meanwhile, slag discharging operation is conducted through an excavator and a slag conveying vehicle, the free face formed by the vertical groove is larger and larger, finally, the free face is communicated to form the tunnel section, excavation of the tunnel on the layer is completed, and the purpose of excavating the whole tunnel can be achieved through repeated operation; and the tunnel construction efficiency is greatly improved.

Description

technical field [0001] The invention relates to the field of tunnel excavation construction, in particular to a construction method for tunnels with arbitrary sections in hard rock formations. Background technique [0002] In recent years, the construction scale of basic projects such as road traffic, water conservancy and hydropower has increased year by year, and tunnel excavation methods and equipment have received more and more attention. Traditional construction methods have been unable to meet the needs of modern tunnel construction, especially for rocks with extreme strength. In high hard rock formations, relying solely on metal tools for excavation not only slows down construction efficiency, but also increases construction costs due to abnormal wear of tools. [0003] The traditional drilling and blasting method is suitable for a wide range of geology, but the construction efficiency is slow, the construction personnel work hard, the working environment is harsh, ca...

AI Technical Summary

Problems solved by technology

[0005] The traditional hard rock TBM construction method generally uses a full-face tunnel boring machine with hard rock hobs arranged on a circular cutter head. Although this construction method has high construction efficiency and low impact on the environment, due to the complex structure of the whole machine, large size, Defects such as high cost and difficult transition also make it difficult to promote

[0006] The traditional oil pressure (water pressure) cracking method is generally applied to the mining of stones with free faces. In tunnel construction, holes are usually drilled directly on the tunnel face to expand cracks. This construction method does not produce cracks and free faces. The subsurface rock mass joints are still connected together, the released in-situ stress is less, and the overall strength does not decrease significantly. Therefore, it is difficult to use oil pressure (water pressure) to expand the construction and the effect is not obvious. If the rock strength is too high, it will also cause oil pressure ( Water pressure) The abnormal damage probability of the expansion cracking rod is increased

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