JPH037795B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a trenchless pipe burying method and an apparatus suitable for carrying out the method.

Trenchless burying methods have been known for burying relatively small-diameter pipes, such as gas pipes and water pipes, on roads with heavy traffic or in urban areas. This construction method generally involves laying a pilot pipe from a starting shaft to a destination shaft, and then sequentially burying the main pipe along the pilot pipe while enlarging the holes with a drilling head.

Various types of excavation heads have been known in the past, and the present inventor previously published Japanese Patent Application No. 56-106288 (Japanese Patent Publication No. 62-34918).
A new excavation method has been proposed. In this construction method, a pilot pipe is excavated and penetrated from the starting shaft to the arrival shaft, and a drilling head is connected to the tip of the pilot pipe that has penetrated to the arrival shaft, and a pipe to be buried is connected to this drilling head, and the pipe is inserted through the pilot pipe. By rotating only the excavation head and drawing it toward the starting shaft side, the hole is expanded and the pipe to be buried that is to be taken to the excavation head is buried. By the way, in such a construction method, in order to discharge the waste soil generated by excavation, a method is adopted in which the waste soil is turned into a slurry and this is sucked. Specifically, when a pilot hole is excavated using a pilot pipe, the excavated earth taken into the pilot pipe by the excavation is turned into a slurry by water supplied from the starting shaft side through the pilot pipe, and this slurry is passed through the pilot pipe again.
On the other hand, in hole expansion drilling using a drilling head following such excavation,
Water is supplied into the excavation head from the starting shaft side through a pilot pipe to turn the waste soil taken into the excavation head into a slurry, and this slurry waste soil is brought to the excavation head using a pump and discharge pipe. It will be discharged to the reaching shaft side through the planned pipe. However, in this method, there are differences between the two excavation processes, such as discharging the soil in the form of a slurry into the starting shaft in pilot pipe excavation, and into the destination shaft in subsequent hole-expanding. In order to discharge the slurry to the other side, there is a problem in that it is necessary to separately install treatment equipment for slurry waste soil in both shafts, or to move it from the starting shaft side to the arrival shaft side after drilling the pilot hole. Also, just looking at hole expansion drilling, water for slurrying is supplied from the starting shaft side and slurry waste soil is discharged to the destination shaft side, so water-related equipment must be installed in both shafts. When it is desired to reuse water, there is a problem in that the water treated in the arrival shaft must be sent back to the starting shaft using a hose or the like.

The present invention was devised in view of these problems, and during hole expansion excavation using a drilling head following the drilling of a pilot hole, the supply of water for discharging waste soil and the discharge of waste soil are all performed by starting the pilot pipe. The present invention aims to provide a construction method that can be carried out on the shaft side and a structure of a drilling head suitable for implementing the method.

For this reason, the pipe burying method of the present invention connects the tip of the pilot pipe that penetrates from the starting shaft to the reaching shaft in the reaching shaft with an excavating head having a drilling bit and an earth intake port on the front side, and The pipe to be buried is connected to the pipe to be buried, and the pipe to be buried is connected to the pilot pipe, and the pipe to be buried is buried by drawing it to the starting shaft side while rotating only the excavation head and drilling to expand the hole, which is carried to the excavation head. During the drilling, driving water is supplied from the starting shaft side through the pilot pipe, and part of this driving water or water separately supplied through the pilot pipe is supplied as slurry water into the drilling head and/or in front of the drilling head, A water jet pump is formed by injecting the other part or all of the driving water toward the pilot pipe inside the suction pipe provided in the excavation head so as to communicate with the soil discharge channel. By the action of the water jet pump, the waste soil taken into the excavation head through the waste soil intake port is sucked through the suction pipe, and is discharged along with the driving water to the starting shaft side through the pilot pipe. shall be.

In addition, in order to carry out such a method, the apparatus of the present invention has a digging bit and a waste soil intake port on the front surface, and a cutting head that is configured to take in waste soil inside. It has a connection part with the pilot pipe and a water injection hole communicating from the inside to the inside of the excavation head and/or the front surface of the excavation head. A cylindrical body in which a flow path for discharging soil is formed is provided, and a suction pipe having one end opened into a hollow part for taking in the discarded soil inside the head is provided at the rear end of the cylindrical body, and the suction pipe is connected to the discharging pipe through the other end. The slurry water flow path is connected to the soil discharge flow path so as to communicate with the water injection hole, and the small diameter pipe that communicates with the drive water flow path is connected to the flow path for driving water in the direction of the pilot pipe. Its feature is that a water jet pump is formed in the suction pipe by connecting it to the suction pipe so that water can be sprayed.

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

The drawings show an embodiment of the apparatus according to the present invention, in which (a) shows an excavation head, and (b) shows a pipe to be buried (hereinafter referred to as a buried pipe) to be connected to the excavation head.

The excavation head of the present invention is composed of a head body 1 and a tube body 2 rotatably connected to the rear part of the head body 1.

The head body 1 has an earth removal inlet and an excavation bit on its front surface, which will be described later.
A cylindrical body 4 is provided at the center of the front surface of the head body 1 so that its rear end side is housed in a hollow portion 3 within the head body 1. This cylindrical body 4 has an open end, and a connecting portion 5 (female threaded portion) for connecting to a pilot tube is formed at this end. Moreover, this cylindrical body 4
A plurality of water injection holes 6 are formed in the drill head and communicate with the inside of the drill head and/or the front surface of the drill head. In this embodiment, the water injection hole 6 communicates with a space 29 between the bit holding member 18 and the head body 1, which will be described later.

A suction tube 7 is connected to the rear end of the cylindrical body 4 . One end of the suction tube 7 communicates with the interior of the cylindrical body, and the other end opens within the head body 1. A water jet pump is formed by connecting a flow path for driving water, which will be described later, to this suction pipe 7. In order to connect the flow path, there is a crankshaft-shaped bend in the middle part in the longitudinal direction. Section 71
is formed. Further, in this embodiment, the bent portion 7
A hanging pipe part 72 bent into a substantially L-shape is provided on the other end side of the suction pipe 7 via a rotary joint 8, and the hanging pipe part 72 is always bent by its own weight as shown in the figure, regardless of the rotation of the suction pipe 7 main body. It is kept in a hanging state to ensure proper suction of excreted soil.

A driving water channel 1 is provided in the longitudinal direction of the cylindrical body 4.
2. A water flow path 13 for slurrying and a flow path 14 for waste soil discharge are respectively formed. That is, the cylindrical body 4
A water introduction pipe 11 having a double pipe structure is provided inside the excavation head for introducing water introduced through the pilot pipe into the excavation head. A small diameter tube portion 113 extends from the inner tube 111 of the water introduction tube 11 into the hollow portion 3 through the cylindrical body, and the bent portion 7 of the suction tube 7
1 in the direction of the cylindrical body.
An air suction pipe 31 is connected to the small diameter pipe portion 113 near this connection portion. Further, a ring body 15 having a through hole 151 for discharging soil is provided between the rear end of the water introduction pipe 11 and the cylindrical body 4. This ring body 15 has one end inside the outer tube portion 112 of the water introduction tube,
Further, the other end has a plurality of communication holes 152 that communicate with each of the water injection holes 6, respectively. In the above configuration, the inner tube section 111 and the small diameter tube section 113 connect the driving water flow path 12 and the inner tube section 111.
The gap between the outer pipe portion 112 and the respective communication holes 152 constitute a slurry water flow path 13, and the inside of the cylindrical body 4 constitutes a waste soil discharge flow path 14, respectively.

At the pilot pipe side ends of the inner pipe part 111 and the outer pipe part 112 constituting the water introduction pipe 11, there are connection parts 16a and 16b (female threaded parts) for supply pipes introduced from the starting shaft side through the pilot pipe. Each is provided. Further, an introduction part 9 having approximately the same diameter as the inner diameter of the suction pipe 7 is formed at the inner rear end of the cylindrical body 4 to which the suction pipe 7 is connected, and a tapered part is formed on the distal end side of the introduction part 9. An enlarged diameter portion 91 is formed. A ceramic member 10 is attached to the inner surface of the introduction part 9.

The water introduction pipe 11 described above has a single pipe structure, and a pipe portion corresponding to the small diameter pipe portion 113 is extended from this pipe body and connected to the suction pipe 7, so that a part of the driving water is converted into slurry water. It is also possible to use it as

To explain the other configuration of this embodiment, in this embodiment, if gravel gets caught in the soil intake port for taking the soil into the head main body, a mechanism is provided to remove it. For this reason, a mounting hole 17 is provided in the center of the front surface of the head body 1, forming a guide cylinder part 101, and the cylindrical body 4 is fitted into this mounting hole 17 so as to be movable in the axial direction of the head body. . In this embodiment, the cylindrical body 4 has a spline shaft shape, and is prevented from rotating in the circumferential direction by being fitted into the mounting hole 17.

A hood-shaped bit holding member 18 is attached to the cylindrical body 4 and has a shape substantially corresponding to the front end of the head body. The bit holding member 18 has a tapered front surface and a short tubular skirt portion 181 at the rear portion, and the inner circumferential surface of the skirt portion 181 slides on the circumferential surface of the head body 1 in the longitudinal direction of the head body. Possibly abutting. The circumferential surface of the head body 1 on the tip side that the skirt portion 181 comes into contact with is the skirt portion 1
In order to absorb the thickness of 81, the diameter is smaller than that of the main body.

A number of excavation bits 19 are provided in the radial direction on the front surface of the bit holding member 18, and a slit-shaped soil intake port 20a for taking the soil into the inside of the bit holding member 18 is provided near each of the digging bits 19. It is provided in the radial direction. Further, a slit-shaped soil intake port 20b facing in the radial direction is also provided on the front surface of the head main body 1. The discharged soil intake port 20a of the bit holding member 18 and the discharged soil intake port 20b of the head body 1 are provided with their positions shifted in the circumferential direction.

Projecting members 21b and 21a are provided on the front surface of the head main body 1 and the back surface of the bit holding member 18 so as to face the discharging soil intake port of the bit holding member 20a and the discharging soil intake port 20b of the head main body 1, respectively. By retracting the bit holding member 18 toward the head body, each projection member 21
Discharge intake ports 20b and 20a facing a and 21b
I am trying to be able to push it into the In this embodiment, the protruding members 21a and 21b are formed of plate-like bodies. There is a rotary joint 2 at the rear of the head body.
4 connects the tube bodies 2. That is, a shaft body 22 is provided at the rear of the head body 1, and this shaft body 22 is connected to the tube body 2 by a bearing that constitutes a rotary joint.
The head body 1 and the tube body 2 are
are rotatably connected to each other. Further, a buried pipe is connected to the rear end of the pipe body 2 by welding or the like.

Further, in this embodiment, a valve 25 for adjusting the amount of soil taken in is provided inside the soil intake port 20b provided on the front surface of the head main body 1. This valve 25 may cause the soil wall to collapse if too much surrounding soil is taken into the head body 1 when excavating soft ground.
The purpose is to appropriately adjust the amount of soil taken in. For this purpose, a flange portion 102 is provided on the inner periphery of the hollow portion 3, and an arm equipped with a valve 25 at the tip is inserted into the insertion hole 26 provided in the flange portion 102 so as to correspond to each discharged soil intake port 20b. 27 are inserted so as to be movable back and forth, and a spring 28 is mounted on the arm 27 between the rear end of the valve 25 and the flange portion 102, and the valve 25 is always pressed by this spring 28.
I am trying to block b. Each valve 25 is
The soil is pushed against the elastic force of the spring 28 by the earth pressure applied to the front surface, and the soil is taken into the hollow portion 3 through the soil intake port 20b.

Next, the method of the present invention will be specifically explained. The drilling head is attached to the tip of the pilot pipe penetrating from the starting shaft A to the reaching shaft B via its connecting part 5, and is drawn toward the starting shaft A while drilling to expand the hole. That is, the excavation head is driven by the drive device 3.
Only the head body 1 is rotated and indexed by the pilot pipe which is rotated and retreated in the direction of the starting shaft by the driving force of zero, and the ground is expanded and excavated by the excavation bit on the front side. And tube body 2
carries the buried pipe to the rear thereof, and follows the head body 1 in a non-rotating state. The buried pipe led to the excavation head is added to the destination shaft B side as the head advances, and the burial is completed when the excavation head reaches the starting shaft A side.

In addition, in such a pipe burying process, the reaching shaft B
The rear end of the buried pipe may be pressed by a pressing device on the side to supplement the propulsive force of the buried pipe.
Without using the above-mentioned pressing device, excavation is performed so that a gap is created between the buried pipe and the soil wall of the excavation hole, and an anti-friction agent is press-fitted into this gap to reduce the peripheral resistance with the soil wall. It is possible to perform excavation while

The soil generated by excavation is first taken into the inner space 29 from the soil intake port 20a of the bit holding member 18, and then introduced into the hollow portion 3 in the main body from the soil intake port 20b on the front surface of the head body 1. It will be destroyed.

In such an excavation process, in the present invention, driving water is supplied from the starting shaft side through a pilot pipe, and part or all of this driving water forms a water jet pump for suctioning waste soil within the excavation head. In the device shown in FIG. 1, when the pilot tube is connected, the two
Supply pipe 2 with a double pipe structure is connected to the water introduction pipe 11, and driving water is supplied to the inner pipe part 111 of the water introduction pipe 11 through the inner pipe part knee 1 of the supply pipe 2, and this driving water The driving water is supplied to the suction pipe 7 through the driving water channel 12 . This driving water is injected in the direction of the cylindrical body 4 at the bent part 71 of the suction pipe, and a water jet pump is formed in this part, and the suction force causes the discharged soil slurry to flow from the open end of the suction pipe 7. The water is sucked and sent into the cylindrical body 4 together with the driving water, and is transferred toward the pilot tube 4 through the through hole 151 and the gap between the water introduction pipe 11 and the inner surface of the cylindrical body.

On the other hand, part of the driving water or water separately supplied through the pilot pipe is supplied as slurry water into the excavation head or the front of the excavation head, or both, to slurry the waste soil,
By doing this, it becomes possible to suction the waste soil from the suction pipe 7 using the water jet pump. In the apparatus shown in FIG. 1, in addition to the driving water, slurry water is supplied to the slurry water flow path 1 of the water introduction pipe 11 from the gap between the external knee 2 and the inner pipe knee 1 of the supply pipe 1.
3 and is injected into the front surface of the head body (inside the space 29) through the flow hole 152. As described above, the slurry-formed waste soil is taken into the hollow portion 3 from the waste soil intake port 20b and sucked by the suction pipe 7.

In this way, in the present invention, driving water and water for slurrying are supplied from the starting shaft side of the pilot pipe, and the waste soil generated by excavation is also discharged to the starting shaft side, so generally the water during pilot hole drilling is Since the supply of water and the discharge of soil are carried out on the starting shaft side, a water treatment device or other water-related devices can all be installed on the starting shaft side.

In addition, to explain other functions of the device of the present invention, in the process of excavation mentioned above, temporarily
If gravel or the like gets stuck in 0a and 20b, clogging them, the excavation is temporarily stopped and the pilot pipe is pushed back toward the excavation head on the starting shaft side. As a result, the cylindrical body 4 slides through the mounting hole 17 into the head main body, and along with this, each protruding member 21
Discharge intake ports 20a and 20b where b and 21a face each other
This is to push out the gravel that has been pushed into the bit and into the outside of the bit holding member or into the head holding body. Thereafter, by pulling the pilot tube, the cylindrical body 4 slides back to its original position, and excavation can be resumed in this state.

According to the present invention described above, not only can long-distance drilling be carried out efficiently in one excavation process without using large jacks etc. and regardless of the soil quality, but also it is possible to drill a pilot hole. In the entire construction process consisting of excavation and subsequent hole expansion drilling, water supply, slurry discharge and treatment can be performed on the starting shaft side, and for this reason, water-related equipment such as water treatment equipment is installed only in the starting shaft. It's enough if you do
Additionally, water can be easily recycled.

Furthermore, since the soil in the excavation head is discharged through the suction pipe that forms the water jet pump, it is possible to efficiently discharge the soil, and since driving water is not supplied to the excavation head, Even when excavating soft ground, pipes can be buried without causing problems such as soil wall collapse or ground subsidence due to too much earth being removed into the head. .

[Brief explanation of drawings]

The drawings show an embodiment of the device of the present invention, in which Fig. 1 is a longitudinal sectional view, Fig. 2 is a sectional view taken along the line - in Fig. 1, and Fig. 3 is a sectional view of a cylindrical body. A front view, FIG. 4 is a cross-sectional view of the cylindrical body and the water introduction pipe taken along the line - in FIG. 1, and FIG. 5 is a schematic explanatory diagram of the state of implementation of the method of the present invention. In the figure, 3 is a hollow part, 4 is a cylindrical body, 5 is a connecting part, 6 is a water injection hole, 7 is a suction pipe, 11 is a water introduction pipe, 12 is a flow path for driving water, and 13 is a slurry water flow 14 is a gap, 16a and 16b are connecting parts, 1
9 is an excavation bit, 20a and 20b are soil intake ports,
A shows the excavation head, b shows the pipe to be buried, and c shows the pilot pipe.

Claims (1)

[Scope of Claims] 1. A drilling head having a drilling bit and an earth intake port on the front side is connected to the tip of the pilot pipe that penetrates from the starting shaft to the reaching shaft, and the excavating head is planned to be buried in this drilling head. The pipe is connected to the pilot pipe, and while rotating only the drilling head, it is drawn toward the starting shaft side and drilled to expand the hole, thereby burying the pipe that is to be buried and brought to the drilling head.During the pipe burying process, the pilot Driving water is supplied from the starting shaft side through a pipe, and part of this driving water or water separately supplied through a pilot pipe is supplied as slurry water into the drilling head and/or in front of the drilling head, and the driving water is A water jet pump is formed by injecting the other part or all of the water toward the pilot pipe inside the suction pipe provided in the excavation head so as to communicate with the soil discharge channel. The waste soil taken into the excavation head through the waste soil intake port is sucked through the suction pipe by the action of the jet pump, and is discharged along with the driving water to the starting shaft side through the pilot pipe. Pipe burying method using open cut method. 2. The excavation head has an excavation bit and an earth intake port on the front side, and is configured to take in the earth inside.The front side of the excavation head has a connection part with a pilot pipe at the tip, and the inside of the excavation head and the excavation head can be accessed from the inside. /Or a cylindrical body is provided in which a water injection hole leading to the front surface of the excavation head is formed, and a driving water flow path, a slurry water flow path, and a soil discharge flow path are formed in the internal longitudinal direction. At the rear end of the cylindrical body,
A suction pipe having one end opened into a hollow part for taking in waste soil inside the head is connected to communicate with the waste soil discharge flow path through the other end, and the slurry water flow path is connected to the water injection hole. A small-diameter pipe communicating with the drive water flow path is connected to a suction pipe so as to inject drive water in the direction of the pilot pipe, thereby forming a water jet pump in the suction pipe. Device.