JPH0224489A - Construction of tunnel in water - Google Patents

Abstract

PURPOSE:To cut down the cost of construction by a method in which the area from a vertical pit to the main pit is excavated for facing by an excavator immersed in water, the muck is separated by solid-liquid separation and discharged to the outside of pit, and segments are supplied from the vertical pit into mud water and assembled. CONSTITUTION:A boom cutter 1 is driven on free cross sectional area in an expandible and direction-changeable manner, during which period facing is excavated in a circular arc form in mud water by a cutter head 5 to form a tunnel 100. The muck is sent through discharge pipes 14 and 15 to a muck treater 16, housed in a dehydrating bag 22, and sent on a conveyer 27. Hollow segment pieces 32 are lowered from a vertical pit 50 into the main pit 100 by a winch 37 to assemble a ringed segment. The ringed segments are advanced by jack groups 31. The weights of the segment pieces 32 are reduced by buoyancy of water, and therefore, handling operation can be made easier, thus raising the operability and safety of construction work.

Description

[Detailed description of the invention] <Industrial application field> This invention is a method of constructing tunnels underwater.

In detail, the present invention relates to a tunnel construction method in which a tunnel is excavated underwater and lined.

<Conventional technology> With the concentration of population in large cities, a highly reliable power supply has become important, and underground substations, underground power plants, power storage facilities using superconducting and compressed air, fuel storage facilities, underground Various energy facilities such as line tunnels and common ditches have become necessary. However, underground in large cities, various facilities and foundations are laid out in all directions, making it extremely difficult to locate new large-scale energy facilities.Therefore, it is difficult to construct tunnels deep underground. has been proposed, and various techniques have been proposed and experiments have been conducted to excavate this tunnel. Furthermore, it is considered advantageous from an economic and technical point of view to install such deep underground tunnels, even in areas where the ground level is soaring or where buildings such as houses and buildings are densely packed. Therefore, the installation of such various energy facilities in urban areas is becoming a reality.

<Problem to be solved by the invention> However, when excavating a large-diameter tunnel in such a deep underground, how to efficiently excavate the tunnel and how to remove the large amount of excavation waste caused by the excavation. Problems arise, such as how to discharge the fuel to the ground and whether it is possible to easily and quickly line a large-diameter tunnel by using segments.

This invention aims to solve the above problems,
The first purpose is to fill the tunnel with muddy water to balance it with groundwater, especially the ground pressure at great depths, so that the tunnel can be dug safely and quickly.

The second aspect of this invention is to efficiently discharge a large amount of waste that has become slurry in water to the outside of the mine.

Furthermore, the third aspect of this invention is to simplify the transportation of segments underwater and the tunnel lining using the segments, thereby making the work easier and ensuring sufficient strength from the earth pressure of the tunnel after completion. .

Means for Solving the Problems This invention has been made based on the above problems,
The gist is that in a tunnel construction method in which the area from the vertical shaft to the main shaft of the tunnel is submerged under water to balance ground pressure with mud water pressure, the method includes a step of excavating the face of the tunnel main shaft with an excavator, and The tunnel is excavated through a process of transporting the waste along with muddy water, separating solid and liquid, and transporting the separated waste outside the mine.

As the tunnel is excavated, segments are supplied from the shaft into muddy water and assembled, and the tunnel is lined by a process in which the segments are propelled forward with jacks, and the muddy water from the shaft to the main shaft is discharged. In the tunnel construction method.

In addition, another aspect of the present invention improves workability by hollowing out the wall thickness of the segment and reducing weight by handling it underwater. We aim to provide a method for constructing tunnels that maintains sufficient strength even under ground pressure by injecting it into a cavity.

<Operation> In this invention, the tunnel is submerged, the ground pressure is balanced with mud water pressure, a face is excavated with an excavator, the excavated waste is made into a slurry with muddy water, and the fluid is transported, and the solid waste and liquid mud are further mixed. Digging the tunnel while separating.

Meanwhile, along with this tunnel excavation, segments are supplied and assembled in muddy water, and then propelled by jacks from the reaction wall of the shaft to line the tunnel.

Each segment has a cavity inside, into which a solidifying agent such as cement milk is injected and hardened in muddy water during tunnel construction or after drainage.

<Example> An embodiment of the present invention will be described below.

In FIGS. 1 and 2, 1 is an existing tunnel excavator installed in a space in muddy water at the tip of a tunnel main shaft 100, and here a boom cutter is used.

As shown in FIGS. 3 and 4, for example, this boom cutter 1 has a main body 2 and an opening arm 3 that can freely move in any direction within a free cross section, which are pivotally connected by a universal joint, and a piston (not shown). A hydraulic cylinder 4 with a cutter head 5 installed therein, and an electric motor (
The cutter head 5 has a cylindrical shape, and the outer periphery and tip surface thereof have a
A needle-shaped bit 7 for excavating the face is provided. Moreover, on the upper part of the main body 2, II! A support arm 9 connected to a hydraulic cylinder 8 for vertically moving the movable arm 3 has both ends pivoted by a universal joint, and drive arms 3 are mounted on both sides of the main body 2.
A support arm 12.13 to which hydraulic cylinders 10.11 for horizontal movement are connected is also pivotally connected at both ends by a universal joint, making it freely movable.

14.15 is a discharge pipe for discharging the waste excavated on the face surface by the boom cutter 1 along with muddy water, and this is connected between directly below the boom cutter 1 and a suction pump 17 provided in the waste processing device 16 at the rear of the tunnel. has been done. In addition,
The tips of the discharge pipes 14 and 15 face the vicinity of the tunnel face. Also.

In order to remotely control the boom cutter 1, a cable bundle (not shown) that includes communication cables for remote control on the ground, communication cables for construction management, etc. is connected to one end of the boom cutter 1.

On the other hand, 18 shown in FIG. 5 is a dehydration bag supply device, which is connected to the end of the discharge pipe 19 of the suction pump 17. This dehydration bag supply device 18 consists of a long cylindrical dehydration bag 22 attached to a plurality of discharge pipes 21 provided on a rotating member 2o. Note that by rotating the rotating member 20 at predetermined angle intervals, any one of the discharge pipes 21 can be made to communicate with the discharge pipe 19.

Reference numeral 23 designates a solid-liquid separator, which includes a porous material 25 facing the through hole 24 and a porous water pipe 26 surrounding the porous material 25. One end of this through hole 24 has a dehydration bag receiving structure into which a dehydration bag 22 containing excavation waste and muddy water is received, and the other end is pipe-shaped, with its tip facing above the conveyor 27. I'm here. In addition, here, the tips of each of the dehydration bags 22 are squeezed and crimped.
The excavation waste and muddy water can be sent into the dewatering bag 22. After storing the excavated waste and the like in this manner, the rear end of the dewatering bag 22 is squeezed and closed, and the vicinity thereof is cut to form a capsule shape, which can be sent to the next process. Note that 22A indicates a dewatering bag containing the excavated waste after dewatering, and if necessary, a bag with a specific gravity of 1 or less may be incorporated therein so as to give buoyancy to the bag and float it on the dirty water surface of the shaft 50. 28 is a power unit as a power source for the suction pump 17, rotating member 20, etc., and 29 is the environment! ! 30 is a cable that bundles a communication cable for remote control for remotely controlling the dehydration bag supply bag R18, a communication cable for construction management, and the like.

Further, reference numeral 31 denotes a group of jacks that propels the ring-shaped segments in which the segment pieces 32 are assembled by being supplied from the shaft into muddy water using a reaction force from a reaction wall 33 installed at the bottom of the shaft 50. Here, the segment piece 32 has an arcuate box shape as a well-known segment as a whole, and a hollow portion 34 is provided within the wall thickness of the segment piece 32 . This cavity 34
A part of the wall may face the end face, but from the perspective of maintaining strength, it is usually a hollow part to create a space within the wall thickness, or the interior is divided into multiple spaces, and these spaces are One or more concrete injection holes communicating with the inside of the excavation cavity can be provided in the center of the inversion or in the ring joint. Incidentally, in terms of manufacturing, it is advantageous that the cavity 34 faces the end face.

In FIG. 6, the segment pieces 32 are raised and lowered by wires 36 and winches 37 for assembly at the bottom of the shaft. Reference numeral 38 denotes a device for carrying out the dehydration bag 22A, which is carried out to the ground by a winch 40 via a wire 39.

In addition, 41 is the winch 37 and 4 installed near the shaft.
0 is mounted on a turret.

Next, the method of the present invention using the above device will be explained.

First, the drive arm 3 installed on the boom cutter 1 is driven by each hydraulic cylinder to expand and contract freely and in any direction, while the cutter head 5 excavates the face in an arc shape in muddy water, and the main shaft 100 of the tunnel is excavated. Form.

Note that the above-mentioned "direction freely" means that the cutter head 5 freely moves within a free cross section by the drive arm 3. Due to the above-mentioned excavation, the sludge collapses into the work area. Then, this excavated waste is turned into slurry with muddy water and discharged into the discharge pipe 14.
15, is sucked in by a suction pump 17 in a waste treatment 16, and sent to a dehydration bag supply device 18.

A long cylindrical dehydration bag 22 is fitted around the discharge pipe 21 of the dehydration supply device 18, and its tip is located in the through hole 24 of the solid-liquid separator 23, with an opening in advance. The discharge pipe 21 is caulked, and the excavated waste is sent together with muddy water through the discharge pipe 21, and at the same time, the water is dewatered through the porous water pipe surrounding the porous material 25. In this way, when a predetermined amount of excavated waste is stored in the dewatering bag 22, the discharge of the excavated waste from the discharge pipe 21 is temporarily stopped, and then the excavated waste is squeezed and caulked to cut off the rear end. It becomes like a capsule capacity and is sent onto the conveyor 27 one after another. In the above-mentioned through hole 24, the dehydration bag 22 passes through the pores of the porous material 25 and the porous water pipe 26 to the part where the porous material 25 is located, and only the muddy water in the dehydration bag 22 is sucked out. It is discharged around the water pipe 26. For this reason, the dewatering bag 22A has a high density and accommodates only excavated waste with low water content.

After this is transferred onto the conveyor 27, it is transported to a predetermined location outside the mine by a lift provided in the shaft. In this case, the dehydration bag 22 is desirably made of a sheet material that prevents muddy water from entering from the outside after dehydration.

When transporting excavated waste in the form of a slurry in this way, if the solid excavated waste is separated by the solid-liquid separator 23 and transported in the dehydration bag 22A, it can be transported without being greatly affected by water pressure. Most of the excavation waste can be easily transported to the ground without transporting heavy muddy water.

On the other hand, the segment piece 32 is suspended from the ground by a wire 36 wound around a winch 37 and lowered into the main shaft 100 from the shaft 50. This segment piece 32 would be extremely large and heavy if it were used for a tunnel with a large cross section, but since it has the hollow portion 34, the weight as a whole is significantly reduced.

For this reason, the segment piece 32 by the wire 36
In addition to making it easier to hang and unload objects, the buoyancy of water can also be used to safely unload objects. Also, when the segment piece 32 is propelled by the jack group 31, it can be moved relatively lightly and smoothly in the axial direction inside the mine, and
By receiving circumferential frictional resistance, a large axial force is not inadvertently applied to the segment piece 32, and problems such as buckling can be solved.

In addition, if a slipping material or reinforcing material is injected into the cavity 34 of the segment piece 32 during lining construction or after drainage, the strength of the tunnel after completion can be further increased. .

In addition, since the segment pieces 32 are obtained by precasting, the quality such as weight and strength is stable. The excavator (boom cutter) 1 is equipped with a screw propulsion device W1 (not shown) at the negative part so that it can move underwater between the face and the shaft part along the discharge pipe 14.15, and parts can be replaced. It is also possible to facilitate the following.

<Effects of the Invention> As explained above, according to the method of this invention, the tunnel is excavated while being submerged from the vertical shaft to the tunnel main shaft. It is possible to prevent tunnel collapse due to walls protruding.

The excavated waste is conveyed by fluid, and the liquid is separated into solid and liquid before being carried outside the mine, so only the solid excavation waste can be transported to deep ground without being affected by water pressure. It can be easily and economically transported from inside space to the ground. In addition, since the solid-liquid separation is carried out in the water, the muddy water treatment equipment on the ground can be small.

It has the advantage of being economical. Further, according to the method of the present invention, it is possible to reduce the weight of the segment, and it is possible to facilitate the propulsion by the propulsion jack during the hoisting work in the mine. There is no need to enlarge the propulsion jack or reaction wall.

It is easy to handle, which reduces construction costs as a whole and improves workability.

[Brief explanation of the drawing]

1 and 2 are partially cutaway conceptual explanatory diagrams of the entire invention; FIGS. 3 and 4 are a side view and a front view of the boom cutter shown in FIG. 1; and FIG. FIG. 6 is a schematic perspective view of the conveying device for excavated waste, and is an overall explanatory view of the present invention. 50... Vertical shaft, 100... Main shaft, 1... Excavator (boom cutter), 16... Scrap processing device, 23... Solid-liquid separation device, 31... Jacket group, 32... Segment piece,
34... Cavity part of segment l-. Figure 3

Claims (1)

[Scope of Claims] 1) A method for constructing a tunnel in which the area from the shaft to the main shaft of the tunnel is submerged under water to balance water pressure with ground pressure and excavate, comprising: excavating the face of the tunnel main shaft with an excavator; A tunnel is excavated by a step of transporting the excavated waste along with muddy water, separating solid and liquid, and transporting the separated waste outside the tunnel, and as the tunnel is excavated, segments are supplied from the shaft into the muddy water. A method for constructing an underwater tunnel, in which the tunnel is lined by a process of assembling and propelling it forward with a jack, and then draining water from the shaft to the main shaft. 2) The underwater tunnel construction method according to claim 1, wherein the segment has a cavity within its wall thickness, and a solidifying agent is injected into the cavity and hardened in the muddy water or after discharge.