JPH0470495A - No-blasting construction method in hard rock tunnel of large section - Google Patents

Abstract

PURPOSE:To improve the excavating efficiency by face-cutting radial slits with a face cutter from inside of a heading, and crushing a wall body between a face and the slit by a breaker from the main tunnel face to excavate a main tunnel. CONSTITUTION:A heating A is excavated by a heating excavator. A large number of a plurality of rows of slits C1 to C5 are face-cut in a rock bed B by a slit cutter 1. Next, a wall body B1, formed by a face E and the slit C in a side of the face E, is crushed by a breaker 2 from a main tunnel D, and a part E1 of a new face is formed by a surface in the interior of the slit C1. Next, the main tunnel D is excavated to a primary tunnel D1 by forming a part E5 of the new face one after another by a similar procedure. Further, the slit is cut in the primary tunnel D1 by the slit cutter 1, and the face E is advanced to excavate a tunnel by repeating a similar procedure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a non-blasting method for hard rock tunnels with large cross-sections where blasting methods cannot be used in tunnel excavation due to restrictions on vibration and noise caused by blasting.

[Conventional technology] When excavating a tunnel, the rock strength is 800 kg/cffl.
In the following cases, tunnel boring machines such as road headers are used for construction, and for rock masses with rock strength exceeding 1000 kg/cnf, tunnel boring machines (TBMs) have been mainly relied upon. However, this tunnel boring machine has drawbacks such as a circular excavation cross section, a diameter of 5 to 6 m, and a high machine cost.

Generally, in large-section tunnels, the mirror surface of the tunnel is excavated little by little using a static crusher, resulting in low excavation efficiency.

An object of the present invention is to provide a non-blasting construction method for large-section hard rock tunnels with high excavation efficiency.

[Means for Solving the Problems] According to the present invention, a guide hole of a size that can be worked by a surface milling machine is excavated by a guide hole drilling machine, and a radial slit or a continuous hole is ground from inside the guide hole by a surface milling machine. Then, the wall between the mirror surface and the slit or continuous hole is crushed by a crusher from the mirror surface of the main shaft, and the main shaft is excavated.

It is preferable to use a tunnel boring machine, a hard rock tunnel excavator, etc. as the guide hole excavator.

Moreover, it is preferable to use a slit cutter or a continuous hole drilling machine as the rigid machine.

Further, it is preferable to use a breaker or the like in the crusher.

[Operation] In the non-blasting construction method for hard rock tunnels with large cross sections, a wall is formed between the slit or continuous hole on the main shaft side and the mirror surface of the main shaft. Therefore, the wall body is easily crushed by a crusher such as a slit cutter, the wall body is easily crushed by the inner surface of the slit or the continuous hole, and a new mirror surface is formed by the inner surface of the slit or the continuous hole. Thereafter, the walls are sequentially crushed in the same manner to efficiently excavate the tunnel main shaft.

[Example] The present invention will be described in detail below with reference to the drawings.

1 and 2, first, a guide hole A is excavated using a guide hole excavator such as a tunnel boring machine or a hard rock tunnel excavator (not shown). The size of the guide hole Δ is set to a size that allows a rigid machine, that is, a slit cutter 1 in the illustrated example, to work thereon. In addition, if the geology is poor,
Support the peripheral wall of the guide hole A with concrete or fiber bolts.

Next, a large number of rows of slits 1-C1 to C5 (hereinafter referred to generically as C) are solidified on the bedrock B using the slit cutter 1. In addition, at this time, slit cutter 1
It is preferable to use multiple machines to speed up tunnel excavation.

Next, the wall B1 formed by the mirror surface E and the slit C on the side of the mirror surface E is crushed by a crusher, that is, a breaker 2 in the illustrated example, from the main shaft, and one part of the new mirror surface is crushed by the inner surface of the slit CI. A part E1 is formed, and a part E5 of the new mirror surface is sequentially formed in the same manner, and the main shaft is excavated to the primary shaft D1.

Next, slits C6 similar to those described above are rigidly made in the primary pit D using the slit cutter 1.

Next, the wall between the mirror surface E and the slit C6 is broken by the breaker 2, and the main shaft is excavated into a secondary shaft D2.

Thereafter, the same procedure is repeated, the secondary shaft D2 is excavated to the main shaft, the mirror surface E is advanced, and the tunnel is efficiently excavated.

[Effects of the Invention] As explained above, according to the present invention, conventional large-sized hole excavators such as tunnel boring machines or hard rock tunnel excavators, rigid machines such as slit cutters, and crushers such as breakers can be used. By using this machine in combination, it is possible to efficiently excavate large-section hard rock tunnels without using blasting.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention, and FIG. 2 is a front view showing a side view of the slit of the primary hole in the left half and the slit of the secondary hole in the right half. A... Leading hole C... Slit D... Main hole
E... Mirror surface 1... Slit cutter 2...
・Playing ability

Claims (1)

[Claims] A guide hole of a size that can be worked by a surface grinder is excavated using a guide hole drilling machine, and radial slits or continuous holes are ground from inside the guide hole using a surface grinder, and a mirror surface and the above-mentioned slits or continuous holes are cut from the mirror surface of the main hole by a crusher. A non-blasting construction method for large-section hard rock tunnels, which is characterized by crushing the walls between the holes and excavating the main shaft.