JPH076238Y2 - Tunnel excavator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a tunnel excavator equipped with a jet pump for conveying excavated soil.

[Prior Art] A conventional tunnel excavator includes, for example, Japanese Patent Laid-Open No. 59-3140.
As disclosed in Japanese Patent No. 0, a muddy water pressurizing system in which a face is excavated while applying a constant muddy water pressure, and a jet pump system in which excavated earth and sand are sucked by a jet pump are known.

FIG. 7 shows a schematic configuration of the muddy water pressurizing method. In the figure, reference numeral 1 is a cut disk for rotating and excavating a cutting face 10 in the front, and a water-tight structure of the cut grass chamber 2 is formed behind the cut disk. A water supply pipe 3 for injecting water into the face is provided at the upper part of this Kattachiyanba 2, and a sludge discharge pipe 4 for discharging excavated earth and sand (hereinafter referred to as excavation sludge) is provided at the lower part. The water supply pipe 3 communicates with a water tank 6 via a centrifugal water supply pump 5, and the mud discharge pipe 4 communicates with a discharge side via a mud discharge pump 7.

In this muddy water pressurizing method, the pressure water from the water supply pipe 3 is supplied into the cutlet chamber 2 so that a constant muddy water pressure is applied to the face 10. In this state, the cutting face 10 is excavated by the cutter disk 1, and the excavation scrap and the muddy water are discharged to the outside of the excavator by the sludge pump 7.

On the other hand, FIG. 8 shows a schematic configuration of the jet pump system. In the figure, a hopper 11 for accumulating excavation chips is provided below the Kattachi yanba 2. A jet pump 12 is arranged below the bottom wall 11a of the hopper 11, and a nozzle 12a of the jet pump 12 is connected to a water supply pipe 3 for supplying water for generating negative pressure. The water supply pipe 3 is provided with two water supply pumps 5, 8. In addition, in the sludge pipe 4, a crusher 13 for finely crushing the drilling scrap,
Atmospheric open tank 14 that removes gas from the components in the sludge pipe
And a sludge pump 7 are provided. Other configurations are 7th
The parts are the same as those in the figure, and corresponding parts are designated by the same reference numerals and the description thereof is omitted.

In this jet pump system, the pressure water supplied from the water supply pipe 3 to the jet pump 12 is accelerated by the nozzle 12a of the jet pump 12 and is decompressed by the throat 12b, so that a negative pressure is generated. Drilling debris is sucked into the jet pump 12, and
After being guided to the atmosphere open tank 14 from 13 and bleeding air, it is discharged to the outside of the excavator by the suction force of the sludge pump 7.

[Problems to be Solved by the Invention] By the way, in the mud pressure method of FIG. 7, mud pressure is applied to the face 10, so when excavating under collapsible geology,
There is an advantage that a so-called earth retaining function that can prevent collapse of the stratum can be obtained.

However, since a muddy water pressure is applied to the watertight cut-out chamber 2, a pressure-resistant seal is used for the earth-and-sand seal portion of the cut-out chamber 2, but when such a pressure-resistant seal is used, the rotation speed of the cutlery disk 1 is increased. There is an inconvenience that the excavation performance is deteriorated as a result of being unable to raise sufficiently.

On the other hand, in the jet pump system shown in FIG.
Since no muddy water pressure is applied to the face 10, the inside of the Kattsachiyanba 2 is maintained at about atmospheric pressure. Therefore, it is possible to use a high peripheral speed seal having poor pressure resistance in the earth and sand seal portion.
There is an advantage that the rotation speed of the cutter disk 1 can be sufficiently increased and the excavation performance is improved.

However, in this jet pump system, since no mud pressure is applied to the face 10, a sufficient mountain retaining function cannot be obtained,
As it is, it is not suitable for excavation of collapsible geology. Therefore,
Conventionally, prior to the construction, it was necessary to perform an auxiliary construction method such as injecting a chemical solution on the collapsible formation to improve the ground.

Usually, before the start of tunnel construction, the geology is investigated, and one of the above-mentioned mud pressure method and jet pump method is adopted according to the result of the investigation. And the jet pump method,
If there are merits and demerits and the geology changes in the middle,
There was a drawback that it was not practical.

This invention was made in view of the above-mentioned conventional problems.
The two excavators can use both the mud pressure method and the jet pump method, which makes it possible to obtain both excellent excavation performance and a mountain retaining function, and also a tunnel excavator that does not require an auxiliary construction method. The purpose is to provide.

[Means for Solving the Problems] In order to achieve the above object, a tunnel excavator according to the present invention collects excavated earth and sand in a Kattachiyanba behind a Katta disk for rotating and excavating a front face. The jet pump is arranged below the bottom wall of the hopper, and the bottom wall of the hopper is provided with an opening communicating with the intake port of the excavated earth and sand of the jet pump. Further, a first supply pipe for injecting into the cutlet chamber, a second supply pipe for supplying water for generating a negative pressure to the jet pump, and a pressure water supply to the first and second supply pipes. And a valve for controlling the distribution amount of the pressure water distributed from the water supply pipe to the first and second supply pipes.

[Operation] According to the present invention, the first supply pipe for pouring water into the excavated soil in the Katutachiyanba and the second supply pipe for supplying water for negative pressure generation to the nozzle of the jet pump are provided, and the first and the above are provided. Since the amount of pressure water distributed to the second supply pipe was controlled by a valve, under geological conditions that are not collapsible,
By supplying pressurized water only to the second supply pipe with the above valve and supplying water for negative pressure generation to the jet pump, the excavated earth and sand can be sucked in by the jet pump, and a jet pump method with excellent excavation performance is adopted. it can.

Further, under collapsible geology, the valve is switched to supply pressure water only to the first supply pipe, and a constant mud pressure is applied to the face to switch to a mud pressure method excellent in mountain retaining function. be able to. Therefore, it is no longer necessary to use a conventional auxiliary method such as chemical injection.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration diagram of a tunnel excavator according to the present invention. In the figure, reference numeral 1 is a cutter disk, and as shown in FIG. 2, a plurality of cutters 1a for excavating the face 10 are mounted. The cutter disk 1 is rotated by a drive motor via a transmission gear (not shown). Reference numeral 22 denotes a sand / sand seal portion, which is made of a material having a high peripheral speed seal resistance, such as urethane rubber. 23 is a pressure-proof bulk head, and 24 is a bearing.

A watertight structure of a Kattachi yanba 2 is formed behind the katta disc 1, and a hopper 30 for accumulating excavation chips is provided below the kattan chimba 2. Accumulation of excavation scraps by the hopper 30 is performed by a bucket 1b which is fixed to the cutter disk 1 and rotates.

The hopper 30 includes a front wall 70 and a front bottom wall welded to the front wall 70.
It is divided into two parts, a front part 30a including 31a and a rear part 30b including a rear bottom wall 31b. The front portion 30a and the rear portion 30b are detachably fastened with bolts 32 as shown in FIG.
71 is a casing of the jet pump 40, and the front bottom wall 31
It is welded to a and its rear end portion 71a is butted to the bulk head 23. The state in which the front portion 30a is removed from the rear portion 30b is shown in FIGS. 4 and 6.

A first supply pipe 51 for pouring water into the excavated earth and sand in the cutlet chamber 2 is supported on the rear bottom wall 31b of FIG.
The first supply pipe 51 has an upper end opening to the upper part of the cutlery chamber 2 and a lower end communicating with the downstream side of the water supply pipe 33 (FIG. 1) via the first valve 61.

Below the bottom walls 31a, 31b of the above-mentioned hopper 30, a jet pump 40 for excavating and excavating is arranged. The pump body 40a of the jet pump 40 includes a nozzle 41 and a throat 41a.
Is provided on the downstream side of the nozzle 41, and an inlet 42 for excavating chips is provided.
Are formed. On the other hand, the bottom walls 31a, 31b of the above-mentioned hopper 30
An opening 43 communicating with the intake port 42 is provided between them.

As shown in FIG. 5, a second supply pipe 52 for supplying water for negative pressure generation to the jet pump 40 is arranged on the side of the pump body 40a of the jet pump 40. The second supply pipe 52 is bent in a U shape, and one end thereof is the second.
Communicates with the downstream side of the water supply pipe 33 through the valve 62 of
The other end communicates with the nozzle 41 (Fig. 2). The pump body 40a is bolted to the suction port of the sludge discharge pipe 45.

The first and second valves 61, 62 of FIG.
It is for controlling the distribution amount of the pressure water distributed from 3 to the above-mentioned first and second supply pipes 51, 52, and is provided inside the bulk head 23 in this embodiment.

Two centrifugal water pumps are provided on the upstream side of the water pipe 33.
35, 36 and a third valve 63 are provided. The upstream water pump 35 communicates with the water tank 6, and the downstream water pump 36 and the third valve 63 are bypassed by a bypass pipe 38. A fourth valve 64 is provided in the bypass line 38. The above third and fourth valves
Reference numerals 63 and 64 are for opening and closing the bypass pipe 38 to adjust the water pressure of the pressure water flowing through the water supply pipe 33.

On the other hand, a sludge pump 47, a pressure-resistant crusher 48, and a storage tank 46 are provided downstream of the sludge pipe 45. The crusher 48 finely crushes the drilling waste carried from the sludge pipe 45 to facilitate transportation, and the storage tank 46 is for removing air components from the sludge pipe 45 during the jet pump system. .

The upper part of this storage tank 46 is a water pipe via a circulation line 55.
This circulation line 55 communicates with the downstream side of the bypass line 38 of 33.
A circulation pump 56 is provided in the. During the muddy water pressurization method, the circulation pump 56 is a water pipe for the water accumulated in the storage tank 46.
Circulate to 33, and from the suction port 45a of the sludge discharge pipe 45 to the crusher 4
It ensures a sludge flow rate of up to 8. Reference numeral 65 is a fifth valve for bleeding air, which is used to prevent the air accumulated in the storage tank 46 to be released to the atmosphere during the jet pump system and prevent the suction capacity of the sludge pump 47 from being lowered.

Next, the operation of the above configuration will be described.

The jet pump system will be used under geological conditions that are not collapsible. That is, the second, third and fifth valves 6 in FIG.
Opening 2,63,65, and the first and fourth valves 6
Cut off 1,64. As a result, the water for generating the negative pressure is supplied only to the second supply pipe 52, and the nozzle 41 of the jet pump 40 is supplied.
When a large negative pressure is generated, the excavation debris in the hopper 30 is sucked into the intake port 42 of the jet pump 40 and flows through the sludge pipe 45 together with the water ejected from the nozzle 41. After that, it is finely crushed by Krassia 48 and stored in a storage tank.
Guided by 46.

In the storage tank 46, the air contained in the excavation gap is released to the atmosphere by the opened fifth valve 65. The excavated sludge thus deaerated is discharged by the sludge pump 47 and transported to a muddy water treatment facility (not shown).

On the other hand, under the collapsible geology, the excavator is switched to the mud pressure system. First, the front portion 30a of the hopper 30 is removed from the rear portion 30b, and the state shown in FIG. 6 is obtained. Further, the second supply pipe 52 and the pump body 40a of the jet pump 40 in FIG.
As shown in FIG. 4, each is removed from the water supply pipe 33 and the mud discharge pipe 45, then the blind plug 55 is bolted to the water supply pipe 33, and the suction pipe 57 is bolted to the suction port of the mud discharge pipe 45. .

In this state, the third and fifth valves 63, 6 shown in FIG.
When 5 is shut off and the first and fourth valves 61, 64 are opened, the pressure water from the water feed pump 35 is fed to the first supply pipe.
It is supplied to 51 and a constant mud pressure is applied to the face 10. In this state, the excavation debris in the cutlet chamber 2 is introduced into the storage tank 46 from the suction pipe 57 through the mud pipe 45 as shown by an arrow A in FIG.

In the storage tank 46, the water contained in the excavation waste is sucked up by the circulation pump 56, circulated in the water supply pipe 33, and reused as water for generating the negative pressure of the jet pump 40. The drainage sludge drained in this way is drained by the drainage pump 47, and like the case of the jet pump system,
Transported to muddy water treatment facility.

According to the above configuration, the first to fourth valves 6 in FIG.
By controlling the opening and closing of 1,62,63,64, it is possible to adopt a jet pump method that exhibits excavation performance in geological conditions that do not collapse, and a mud pressure method that exerts a retaining function in geological conditions that are collapsible. Can be switched to. Therefore, it is possible to excavate all geology from hard rock to soft soil including collapsible geology using one excavator.

Moreover, since the mountain retaining function can be obtained as described above, it is not necessary to perform auxiliary construction methods such as conventional chemical solution injection, so the construction cost and labor are greatly reduced, and therefore the construction unit price and excavation are reduced. Work can be improved.

Further, in this embodiment, since the front part 30a of the hopper 30 is removed from the rear part 30b and the muddy water pressurizing system is adopted, as shown by an arrow A in FIG. 6, from the lower part of the cutlet chamber 2 to the suction pipe 57. The flow of excavation and muddy water becomes smooth.

[Advantage of the Invention] As described above, according to the present invention, by controlling the valve, it is possible to set either the jet pump method or the mud pressure method, so that an all-geological tunnel excavator can be obtained. . Moreover, since it is not necessary to carry out an auxiliary construction method such as chemical injection, the construction cost and labor can be greatly reduced.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a tunnel excavator according to the present invention,
Fig. 2 is an enlarged cross-sectional view near the cut sword, Fig. 3 is an enlarged cross-sectional view of the hopper, Fig. 4 is a plan view showing a state in which the front portion of the hopper is removed, and Fig. 5 is a state in which the front portion of the hopper is attached. Fig. 6 is an enlarged cross-sectional view of the vicinity of the cut yanba in the state of adopting the mud pressure method, Fig. 7 is a schematic configuration diagram of the conventional mud pressure method, and Fig. 8 is a schematic view of the conventional jet pump method. It is a block diagram. 1 …… Kutta disk, 2 …… Kutachiyanba, 10 ……
Face, 30 …… Hopper, 31a, 31b …… Bottom wall, 33 …… Water pipe, 40 …… Jet pump, 42 …… Intake port, 43 …… Opening, 51 …… First supply pipe, 52 …… Second supply pipe, 61,62
……valve.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-59-31400 (JP, A) JP-A-60-152799 (JP, A)

Claims (1)

[Scope of utility model registration request] 1. A cutter disk for rotating and excavating a front face, a hopper for accumulating the excavated earth and sand provided in a Kattachiyanba behind the cutter disk, and a hopper disposed under the bottom wall of the hopper. A jet pump, an opening provided in the bottom wall of the above-mentioned hopper and communicating with an intake of excavated soil of the above-mentioned jet pump, a first supply pipe for injecting water into the above-mentioned Kattachi yanba, and water for generating a negative pressure to the above-mentioned jet pump Second supply pipe, the above-mentioned first supply pipe and second
Tunnel excavator comprising a water supply pipe for supplying pressure water to the supply pipe of the above and a valve for controlling the distribution amount of the pressure water distributed from the water supply pipe to the first and second supply pipes. .