JPH11280373A - Starting device and method for portal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily open a portal in a ground tunnel by providing a guide way at the front face of a mountain slope and assembling a lining frame body and pressing the lining frame body on the ground through anchor steel wires to excavate the inside. SOLUTION: A base ground is formed at the front face of a mountain slope 1 and a guide way 6 is laid and boring holes 4 are bored along the outer periphery of a planned line 2 for excavating a tunnel and further, anchor steel wires 5 are arranged to anchor them in the ground with mortar or the like. Then, a lining frame body 9 is assembled on the guide way 6 and a cutting edge 10 is attached to the tip thereof and the anchor steel wires 5 are connected to a center hole jack 7 through a pressing frame 8 and the lining frame body 9 is pressed on the ground to excavate the inside. A tunnel boring machine may be assembled on the guide way 6 to start excavating the ground by thrusting jacks of the machine by making use of reaction force from the pressing frame 8. Accordingly, a portal for a ground tunnel can be easily opened and a tunnel boring machine can be started.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to the construction of a mountain tunnel, in which a pit is opened and excavation into the tunnel is started.

[0002]

2. Description of the Related Art Conventionally, in opening a tunnel entrance of a mountain tunnel, a mountain roof such as a pipe roof or a front surface is cut deep in order to suppress a landslide on a slope or a collapse of a cliff. Also, when starting the tunnel boring machine, there was no reaction body at the wellhead, so we dug the preparation tunnel by hand and started from there.

[0003]

In the conventional method, the front surface is cut deeply, and when the amount of cut is increased, the side surface is exposed to that extent, and the cutting or staking work of this side surface is increased. As a result, it was not economical. Also, when starting a tunnel boring machine, it was necessary to dig a base tunnel for starting by hand, which was an irrational construction method.

[0004]

According to the present invention, a part of a pipe roof for wellhead protection is also used as an anchor steel wire anchoring hole to form a reaction force, and a lining frame and a gate structure are provided in front of a wellhead. The present invention proposes a method of assembling and opening a wellhead portion while pushing in the collapse of the front surface and the side wall to suppress collapse. The procedure is performed as follows. (B) A guideway will be laid with a base in front of the wellhead. (B) A plurality of boreholes are dug along the perimeter of the planned section of the tunnel, steel wires or steel rods are placed there, and they are anchored to the ground with mortar or the like to make anchors. (C) assembling the lining frame on the guideway,
A pressure frame is placed on the rear side, a center hole jack is installed, and fixed through an anchor steel wire. (D) At the end of the lining body, a cutting edge having a removable hood is provided. (E) Excavate the wellhead by pressing the frame against the front of the wellhead. (F) An aggregate is applied to the outer surface of the skeleton to gradually reduce friction, thereby exerting the function of retaining the upper surface and side surfaces. (G) In the method according to the third aspect, the tunnel boring machine is assembled on the guideway, the machine is pressed against the ground surface by the same operation, and the pressing frame is used as a reaction force. The propulsion jack of the machine starts and starts excavation.

[0005]

According to the method for starting a wellhead according to the present invention, by precasting the wellhead, it is possible to easily cope with various shapes such as a projecting type, an upright wall, and a slope wall. In addition, by assembling and pushing these at the wellhead, the slope of the wellhead can be stabilized, and a reaction force for starting the tunnel boring machine can be obtained, so that the wellhead can be opened without waste.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG.
1 is an overall side view showing an embodiment of the present invention. 1 represents the slope of the mountain about to tunnel.
Reference numeral 2 denotes a planned line for tunnel excavation. Reference numeral 3 denotes a pipe roof that protects against collapse due to tunnel excavation. Reference numeral 4 indicates a situation where an anchor steel wire is fixed in a borehole. Reference numeral 5 denotes an anchor steel wire, which is inserted into the center hole jack 7 through the pressurizing frame 8. Reference numeral 9 denotes a lining frame and a gate frame or a tunnel boring machine, which is assembled on a guideway 6. Reference numeral 10 denotes a blade for pushing, which is attached to the head of the skeleton. Jack 7
Is operated to press the cutting edge 10 against the ground, excavate inside the cutting edge, and further excavate while operating the jack to press-fit. FIG. 2 shows an example of a conventional wellhead opening method, and is a diagram showing a tunnel lining frame 12, a wall surface 13, and a side wall 14. FIG. This indicates that a large-scale cut is required to open the tunnel entrance 11.
FIG. 3 is a perspective view showing a completed state when constructed according to the present invention. With almost no cutting of the ground,
A wellhead can be opened. Reference numeral 15 denotes a precast lining frame and a gate frame.

[0006]

According to the present invention, it is possible to safely and economically open a tunnel entrance on a slope or a steep cliff where a landslide may occur. Although a method of assembling a precast product into the lining of the pit and embankment has already been implemented, in the present invention, the lining skeleton can be positively pushed deep into the wellhead and pushed in. Finally, a gate can be opened by assembling and pressing the gate structure. According to the method of the present invention, earth retaining work can be omitted, a tunnel can be opened without deteriorating the scenery, no additional equipment is required in terms of lighting, and the field of view at the tunnel is widened. It is possible to build a gate with such an effect in a narrow work base, within an economical construction period, and at an economical cost.

[Brief description of the drawings]

FIG. 1 is an overall side view showing an embodiment of the present invention.

FIG. 2 is a diagram showing an example of a conventional wellhead opening method.

FIG. 3 is a perspective view of a projecting type portal showing an embodiment of the present invention.

[Explanation of symbols]

1 Slope of the mountain where a pit is to be opened 2 Planned tunnel excavation line 3 Pipe roof 4 Anchoring section of anchor steel wire 5 Anchor steel wire 6 Guideway 7 Center hole jack 8 Pressurizing frame 9 Lining frame, mine gate frame, tunnel boring・ Machine 10 Cutting port 11 Well port 12 Gate 13 Face wall 14 Side wall 15 Precast gate (projection type)

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] April 9, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

Title: Starting device and starting method for tunnel entrance

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claim 1

[Correction method] Change

[Correction contents]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction contents]

[0004] A lubricant is applied to the outer surface of the skeleton to gradually reduce the friction so that the upper surface and the side surfaces can perform the function of retaining the mountain.

Claims (3)

[Claims] At the opening of a tunnel entrance of a mountain tunnel, a plurality of anchor steel wires or steel rods are fixed to the ground around the planned cross section of the tunnel to generate a reaction force, and a guideway is laid at a wellhead base. A starting device for a wellhead between tunnels, comprising connecting a pressure frame, a center hole jack and an anchor steel wire. 2. A precast lining structure and a portal structure of a tunnel are assembled between the pressurizing frame on the guideway and the ground surface of the wellhead using the wellhead starting device described in claim 1, A method of opening a wellhead, which comprises operating a center hole jack to press the frame against the wellhead surface, and then opening the wellhead by excavation and press-fitting. 3. A tunnel boring machine is installed between the pressurizing frame on the guideway and the ground surface of the wellhead using the wellhead starting device described in claim 1, and the center hole jack is operated. The tunnel boring machine is pressed against the wellbore, and then the tunnel boring machine itself starts excavating itself.