JP2793670B2 - Underground exploration method and apparatus in front of underground excavator - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method for exploring underground conditions in a drilling area through at least an underground excavator before excavation, and an apparatus useful for the method. It is about.

[Prior art] For example, according to a tunnel method such as a propulsion method, if there is an obstacle such as an existing pipe, rock, driftwood or the like in an excavation area in front of an underground excavator, the excavation efficiency is reduced, and in some cases, May not be able to dig. In order to avoid such an inconvenience, a search for an underground obstacle using a radar has been conventionally performed prior to an excavation by an underground excavator.

FIG. 12 and FIG. 13 are diagrams illustrating a conventional typical method used for searching for the above-described obstacle, and show a conventional underground searching method using radar. In the method shown in FIG. 12, a unidirectional antenna 1 serving as a transmitting unit and a receiving unit is provided on the ground surface 2 to radiate pulse radio waves into the excavated area under the ground and reflected by the obstacle 3 under the ground. The wave is caught by the antenna 1 on the ground surface 2 and the presence or absence of an obstacle or its position is to be known. In the method shown in FIG. 13, the boring holes 5, 5 are drilled from the ground surface 2 so as to sandwich the excavation area 4 under the ground, and the non-directional The antenna 3 is inserted to detect the obstacle 3 between the antennas 6 and 6.

[Problems to be solved by the invention]

According to the search method from the ground surface 2 shown in FIG. 12, there is a problem that only a position very close to the ground surface 2 can be searched, and obstacles arranged vertically cannot be identified. For this reason, in the case of underground excavation work that passes through a considerable depth like a tunnel excavator, it has been practically impossible to search the excavated area from the ground surface. Therefore, when investigating a deep position, the exploration method shown in Fig. 13 described above was used.However, according to this method, a large number of In order to drill the boring hole 5, it is necessary to investigate the presence or absence of obstacles. Further, even with this method, it is difficult to determine a target overlapping vertically or horizontally.

The present invention has been made in order to solve these problems, and an underground exploration method and an underground exploration apparatus useful for the underground excavation method capable of reliably exploring a forward obstacle before an underground excavator passes therethrough It is intended to provide.

[Means for solving the problem]

An underground exploration method in front of an underground excavator according to claim 1 includes drilling a small-diameter hole of a predetermined length along the excavating direction of the underground excavator, and inserting a guide tube into the small-diameter hole. Providing an omni-directional antenna section of a pulse radar inside the guide tube to radiate a pulse in the entire circumferential direction of the guide tube, thereby exploring at least an underground condition within a range where an underground excavator passes. And

Further, the underground exploration device of claim 2 is a drilling device for drilling a small-diameter hole of a predetermined length along the excavation direction of the underground excavator, and a guide pipe inserted into the small-diameter hole. And a pulse radar having a non-directional antenna unit movably provided in the guide tube.

According to the underground exploration method of claim 3, a non-metallic propulsion pipe is pressed into the ground to drill a small-diameter hole having a predetermined length along the excavation direction of the underground thruster, Insert the omnidirectional antenna part of the pulse radar into the propulsion tube in the small-diameter hole,
It is characterized in that a pulse is emitted from the antenna section in the entire circumferential direction of the propulsion pipe, and at least an underground situation within a digging range where the digging machine passes is searched.

Further, according to the underground exploration apparatus of claim 4, a non-metallic propulsion pipe is pressed into the ground to drill a small-diameter hole of a predetermined length along the excavation direction of the underground thruster. A pulse radar having an omnidirectional antenna unit movably provided inside the propulsion pipe having a small-diameter hole drilled therein.

[Action]

Prior to underground excavation, a small-diameter hole having a predetermined length is drilled in front of the underground excavator along the excavation direction of the underground excavator by a drilling device. A guide tube is inserted into the small-diameter hole, and an antenna portion of the omnidirectional pulse radar is provided inside the guide tube. Then, a pulse is emitted in the entire circumferential direction of the guide tube, and at least the underground condition within the excavation range of the underground excavator is searched.

Alternatively, prior to the excavation, a non-metallic propulsion pipe is press-fitted along the excavation direction of the underground excavator to drill a small-diameter hole, and a non-metallic propulsion pipe is provided inside the small-diameter hole. Insert the antenna part of the directional pulse radar. Then, a pulse is emitted in the entire circumferential direction of the propulsion pipe, and at least the underground condition within the excavation area of the underground excavator is searched.

〔Example〕

An underground exploration method and apparatus according to a first embodiment of the present invention will be described with reference to FIGS.

In these figures, reference numeral 10 denotes a tunnel machine as an underground machine. This tunnel machine 10 is a device that excavates underground by driving a cutter bit provided at the tip of a shield, and is widely used to excavate a tunnel having a large diameter (for example, a diameter of 2 m or more) at a considerable depth. Have been.

As shown in FIG. 1, prior to excavation, a small-diameter hole 12 is drilled in the soil in front of the tip of a tunnel excavator 10 by a small-diameter drilling device 11. This drilling device 11
Cutter at the front end of the boring pipe 13 with both ends open
The boring pipe 13 is rotatably driven while appropriately adding the boring pipe 13 so as to dig forward, and discharge the soil from the rear end of the boring pipe 13.

As shown in FIG. 2, a small-diameter hole 12 having a desired length is formed along the excavation direction of the tunnel excavator 10 in an excavation area in front of the tunnel excavator 10.

As shown in FIG. 3, a guide pipe 15 is inserted into a boring pipe 13 of the drilling device 11. The guide tube 15 is made of vinyl chloride, has a closed front end and an open rear end, is slightly longer than the entire length of the small-diameter hole 12, and has a rear end provided with a tunnel excavator.
Protrudes into the interior of 10.

As shown in FIG. 4, the boring pipe 13 is pulled out while leaving the guide pipe 15 underground.

As shown in FIG. 5, the rod-shaped antenna 21 of the radar device 20 is inserted into the guide tube 15.

The radar device 20 is a pulse radar that emits a narrow pulse with a sharp rising edge, and includes an operation unit 22, an antenna unit 21, a display unit 23, and a recording unit 24 as shown in FIG. The antenna unit 21 has a rod-shaped half-wavelength broadband diball antenna 25 (antenna 25) and a transmitting / receiving unit 26. This antenna 25 is omni-directional, and the guide tube 15
Can emit a pulse signal in the entire circumferential direction orthogonal to the longitudinal direction. In the transmitting / receiving unit 26, the operation unit 22
Pulse generator 27 by the trigger pulse supplied from
Generates a narrow pulse signal, and this pulse is selectively applied to only the antenna 25 via the TR circuit 28. In addition, the antenna
The reflected energy received by 25 enters a sampling circuit 29 via a TR circuit 28.
Numeral 29 is configured to perform a sweep synchronized with a transmission pulse by a scanning signal supplied from the operation unit 22. Next, the recording unit 24 is constituted by, for example, a tape recorder, and can record the received signal output on a tape. The display unit 23 is configured by, for example, a graphic recorder, and can display an image of the underground situation based on the received signal output.

Although not shown, a moving unit is provided in the antenna unit 21 so that the antenna unit 21 can be set at an arbitrary position in the guide tube 15.

The antenna unit 21 is pushed down to the tip of the guide tube 15. Then, as shown in FIG.
A pulse signal is radiated in the entire circumferential direction of the guide tube 15 while being drawn toward the direction 10, and a cylindrical region centered on a region through which the tunnel machine 10 passes is searched over a range of 360 °. In order to search for obstacles or the like during excavation, it is sufficient to at least search for an area where the tunnel excavator 10 passes, but as in the present embodiment, the diameter of the tunnel excavator 10 is larger than the outer diameter of the tunnel excavator 10. It is better to explore the area.

From the above exploration results, the underground situation in front of the tunnel excavator 10 can be grasped in the section in the longitudinal direction of the small-diameter hole 12, and the position of an obstacle or the like can be known before excavation.

Although the first embodiment described above is applied to construction by a tunnel machine, the method and apparatus of the present invention can also be applied to a small-diameter propulsion method. Further, the pulse radar used in the present invention may be any one having an omnidirectional antenna that radiates a pulse signal over a range of 360 °, and the configuration of the radar device is not limited to the embodiment. For example, a radar device having an antenna as a broadband device described in Japanese Patent Publication No. 55-44916 can be used.

Next, a second embodiment of the present invention will be described with reference to FIGS. The same components as those in the first embodiment are denoted by the same reference numerals.

This embodiment is based on the existing sewer pipe 30 buried underground.
The present invention relates to a construction for connecting a drainage pipe 31 to the ground and connecting the drainage 31 on the ground to the sewer pipe 30, and is useful for confirming the presence or absence of an obstacle at the laying position of the pipe.

First, as shown in FIG. 8, a boring machine 32, which is a drilling device of an underground exploration device, is installed on the ground. This boring machine 32 has a drill bit at the tip of a steel propulsion pipe 33.
34, and can be propelled underground at a desired angle. Then, drilling is performed by the boring machine 32 according to the laying position and direction of the mounting pipe indicated by the dashed line in the figure.

Next, as shown in FIG. 9, a guide pipe 36 which is a non-metallic pipe is inserted into the formed bore hole 35 as a small-diameter hole, and a steel propulsion pipe 33 is pulled out. And the guide tube 36
The antenna unit 21 of the radar device 20 is inserted into the inside, and a pulse is radiated in the entire circumferential direction of the guide tube 36 in the same manner as in the first embodiment to search for an obstacle in the area where the mounting tube is laid.

Although the above-described propulsion pipe 33 is a steel pipe, if the boring hole 35 is excavated with a propulsion pipe made of a nonmetallic pipe, the boring hole
It is not necessary to insert the guide tube 36 into the 35 again, and the antenna section 21 can be directly inserted and searched.

Conventionally, this type of construction has been conducted by digging and excavating, so that the survey was restricted by traffic regulations and caused problems such as traffic obstacles. However, according to the method according to the present embodiment, it is not necessary to dig a road, and no traffic obstruction occurs due to the investigation work, so that the investigation can be performed extremely effectively and safely.

Next, a third embodiment of the present invention will be described with reference to FIGS. The same components as those in the first embodiment are denoted by the same reference numerals.

This example illustrates a method and apparatus useful for exploring for the presence or absence of obstacles within the range of an underground excavator prior to underground excavation work between shaft 40 and shaft 41. Things.

First, as shown in FIG. 10, a boring machine 42, which is a drilling device of an underground exploration device, is installed in a shaft 40 on the starting side. The boring machine 42 has a propulsion pipe 43 that is pressed into the ground, and an inner pipe 45 that is inserted into the propulsion pipe 43 and rotates to excavate with a drill bit 44 at the tip.
Preliminary boring is performed by the boring machine 42, and a small-diameter bore hole 46 is penetrated between the shaft 40 and the shaft 41.

Next, as shown in FIG. 11, a non-metallic guide tube 47 is inserted into the boring hole 46 so that the propulsion tube 43 and the inner tube 45 are inserted.
Pull out. A radar device is provided inside the guide tube 47.
The 20 antenna sections 21 are inserted, and a search is performed in the same manner as in the first and second embodiments. In this case, as in the second embodiment, if the propulsion pipe is made of a non-metallic pipe, it is not necessary to use the guide pipe 47, and the drill bit 44 and the inner pipe 45 are pulled out and the antenna section 21 is inserted directly into the propulsion pipe. And immediately conduct exploration.

If the preceding boring holes 46 used for the search are formed in several places in consideration of the search range of the electromagnetic wave, and the search is performed for each hole, the search range can be expanded. Further, the preceding boring hole may be formed not only in the excavation area but also in a region near the same area and along the excavation direction.

〔The invention's effect〕

According to the method and apparatus of the present invention, an omnidirectional radar antenna is inserted into a small-diameter hole provided along the excavation direction of an underground excavator prior to excavation by an underground excavator, and a 360 ° range is provided. Underground exploration can be performed. Therefore, the presence or absence or position of an obstacle can be confirmed before the excavator passes,
The excavator can be prevented from damaging the main existing pipeline, and troubles and breakdowns of the excavator due to obstacles can be prevented. In addition, it is possible to search for a cavity at a position where the excavator passes and a loose face.

[Brief description of the drawings]

1 to 6 are schematic sectional views of a tunnel excavator and an underground exploration apparatus of the first embodiment, and are process diagrams showing an underground exploration method according to the first embodiment, and FIG. 8 and 9 are schematic sectional views showing the underground exploration method and apparatus of the second embodiment, and FIGS. 10 and 11 are the third embodiment. FIG. 12 and FIG. 13 are conceptual diagrams showing a conventional underground exploration method using a radar. 10 tunnel tunnel machine as underground machine, 11 drilling device, 12 small bore hole, 15 guide tube, 20 radar device as pulse radar, 21 omnidirectional antenna Antenna part as part, 32,42 ... boring machine as drilling device, 35,46 ... boring hole as small diameter hole, 36,47 ... guide pipe.

──────────────────────────────────────────────────続 き Continued on the front page (73) Patent holder 999999999 Nagasawa Industry Co., Ltd. 164 Chizusa-cho, Chiba-shi, Chiba (73) Patent holder 999999999 Fujitecom Co., Ltd. 1-11 Kanda Izumi-cho, Chiyoda-ku, Tokyo (72) Invention Katsukuni Ashino 3-1-2 Takada, Chigasaki City, Kanagawa Prefecture (72) Inventor Koji Kitazume 5-11-15 Chuo, Nakano-ku, Tokyo (56) References JP-A-1-280286 (JP, A) JP-A Heihei 2-179492 (JP, A) Japanese Utility Model Showa 60-32493 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G01V 3/12 G01S 13/88 E21D 9/06

Claims (4)

(57) [Claims] 1. A small-diameter hole having a predetermined length is drilled along an excavation direction of an underground excavator, and a guide pipe is inserted into the small-diameter hole.
Providing an omni-directional antenna part of a pulse radar inside the guide tube to radiate a pulse in the entire circumferential direction of the guide tube, and exploring at least an underground condition in an excavation area through which an underground excavator passes. Underground exploration method ahead of the underground excavator. 2. A drilling device for drilling a small-diameter hole having a predetermined length along an excavation direction of an underground excavator, a guide pipe inserted into the small-diameter hole, and movable into the guide pipe. And a pulse radar provided with an omnidirectional antenna unit provided in the underground excavator. 3. A non-metallic propulsion pipe is pressed into the ground to drill a small-diameter hole of a predetermined length along the excavation direction of the underground propulsion machine.
An omnidirectional antenna part of a pulse radar is inserted into the propulsion pipe in the small-diameter hole, and a pulse is radiated from the antenna part in the entire circumferential direction of the propulsion pipe within an excavation area where at least an underground excavator passes. An underground exploration method in front of an underground excavator, characterized by exploring an underground situation of the underground. 4. A drilling device for press-fitting a non-metallic propulsion pipe into the ground to drill a small-diameter hole of a predetermined length along the excavation direction of the underground thruster, and drilling the small-diameter hole. And a pulse radar having an omnidirectional antenna unit movably provided inside the propulsion pipe.