JPH08304559A - Equipment and method for investigating front of tunnel - Google Patents

Abstract

PURPOSE: To obtain an equipment and a method for investigating the front of a tunnel which conducts reliable and economical investigation of geological features of the front of facing without hindering tunnel excavation work. CONSTITUTION: The vibration at the time of boring of facing 21 is picked up by a vibration pickup 11, while a hole-cutting sound at the time of cutting is collected by a sound collecting microphone 12, and they are converted into vibration acceleration and a sound pressure respectively. The vibration acceleration and the sound pressure thus acquired are compared with the known data on the vibration acceleration and the sound pressure made to correspond to all geological features beforehand and the geological features in the front of the facing are thereby known.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel forward exploration device and method for exploring the geology in front of a tunnel face.

[0002]

2. Description of the Related Art As a method of avoiding a face collapsing accident in tunnel construction, it is important to know the geology in front of the face accurately. The method for investigating the geology in front of the face is roughly classified into the drilling exploration method using the preceding boring and the non-fracturing exploration method using the radio wave (Rayleigh wave). The former exploration method is a method in which the geology of the tunnel excavation planned position is investigated in advance by boring from the surface,
The latter exploration method is a method of exploring the geology in front of the cutting face by attaching a vibrator that gives vibration to the face and a vibration receiver and applying vibration while changing the frequency of the Rayleigh wave.

[0003]

The above-mentioned conventional geological exploration technique for the front of the face has the following problems. <a> In the former exploration method, the geology of the unbored area is unknown because the boring interval is relatively wide. Further, if the boring interval is narrowed, a large time and economic burden is required for boring. <B> In the latter method, it is necessary to attach and detach a large exciter according to the progress of tunnel excavation, which requires a lot of work to attach and detach the exciter, and is uncertain in terms of exploration performance. Remains.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to enable exploration without obstructing tunnel excavation work and to accurately and accurately determine the geological condition in front of the face. It is to provide a tunnel forward exploration device and exploration method that can be economically grasped.

[0005]

SUMMARY OF THE INVENTION The present invention is a vibrometer which electrically senses the vibration of a perforating tool for perforating a face.
It is a tunnel forward exploration device that is configured by a frequency analyzer that calculates the vibration acceleration of a face based on the vibration information obtained by the vibrometer and compares it with known comparison data according to the geology. In addition, a sound collecting microphone that collects the cutting sound of the cutting face, a sound level meter that converts the cutting sound obtained by the sound collecting microphone into sound pressure, and sound pressure information obtained by the sound level meter are known comparisons according to the geology. It is a tunnel forward exploration device composed of a frequency analyzer for comparing with data. Also, with a vibrometer that electrically senses the vibration of the punching tool that punches toward the face,
The vibration acceleration of the face is calculated based on the sound collecting microphone that collects the cutting sound of the face, the sound level meter that converts the cutting sound obtained by the sound collecting microphone into sound pressure, and the vibration information obtained by the vibrometer. In addition, the tunnel forward exploration device is configured by a frequency analyzer that compares the vibration acceleration of the face and the sound pressure information obtained by the sound level meter with known comparison data corresponding to the geology.

Further, the vibration of the punching tool for punching toward the face is detected, the vibration acceleration of the face is calculated based on the vibration information, and then the face in front of the tunnel is compared with the known comparison data according to the geology. It is a tunnel forward exploration method that seeks the geology of. In addition, the cutting sound of the cutting face is collected, the cutting sound obtained by the sound collecting microphone is converted into sound pressure, and the sound pressure information is compared with known comparison data according to the geology to determine the geology of the cutting face in front of the tunnel. This is the method of exploring ahead of the tunnel. Also, the vibration of the punching tool that punches toward the face is obtained as the vibration acceleration, the cutting noise of the face is obtained as the sound pressure, and compared with the known comparison data according to the geology based on the vibration acceleration information and the sound pressure information, respectively. This is a method for exploring the front of the tunnel, in which the geology of the face in front of the tunnel is obtained.

[0007]

Embodiment 1 An embodiment of the present invention will be described below with reference to the drawings.

<B> Tunnel exploration device The tunnel exploration device 10 includes a vibration pickup 11 attached to a jumbo drifter 30 used for boring a face 21 of a tunnel 20 excavation site, and a vibration pickup 11.
The vibrometer 40, which can transmit the vibration during drilling, and the face 21
A sound collecting microphone 12 arranged in the front, a sound level meter 50 capable of transmitting a punching sound from the sound collecting microphone 12, a vibrometer 40, and a data recorder 6 for recording information taken in by the sound level meter 50.
0 and a frequency analyzer 70 that processes and analyzes the data in the data recorder 60.

<B> Vibration Pickup The vibration pickup 11 is a well-known pickup attached to the rear part of the jumbo lifter 30 which is a punching machine, and the jumbo lifter 3 which is drilling along with the geological change.
The purpose is to pick up subtle vibration changes transmitted to zero.

<C> Vibrometer The vibrometer 40 is a meter that collects vibrations and their changes transmitted to the jumbo drifter 30 collected by the vibration pickup 11 as vibration acceleration, and a known vibrometer can be used. Is.

<D> Sound Collecting Microphone The sound collecting microphone 12 is a microphone for installing a sound near the face 21 and collecting a sound and a change in the sound generated during drilling by the jumbo lifter 30. As the sound collecting microphone 12, basically, a known microphone can be used. In the present embodiment, as an example thereof, a case of using a 1/2 inch condenser microphone with a windscreen attached will be described.

<E> Sound level meter The sound level meter 50 is a meter that collects, as a sound pressure, the punching sound generated at the time of punching using the jumbo drifter 30 collected by the sound collecting microphone 12 described above. It can be used.

<F> Data Recorder The data recorder 60 is a known recording device for recording the data collected as vibration acceleration and sound pressure converted by the vibrometer 40 and the sound level meter 50.

<G> Frequency Analyzer The frequency analyzer 70 is an instrument for analyzing and analyzing the data of the vibrometer 40 and the sound level meter 50 recorded in the data recorder 60, and is obtained from the vibrometer 40 and the sound level meter 50. The vibration acceleration and sound pressure data are subjected to frequency analysis, and the geology in front of the cutting face 21 can be grasped from the frequency characteristics.

[0015]

[Operation] The method for exploring the tunnel front will be described below. At the time of conducting an exploration, it is the first essential that the comparative value which is a reference for vibration acceleration and sound pressure analysis / analysis is set in advance by using the exploration method of the present invention on the ground whose geology is known in advance. It becomes a condition. The method of setting the comparison value is also performed according to the following description.

<A> Vibration Detection In the tunnel 20 under excavation, the vibration pick-up 11 attached to the jumbo lifter 30 detects the vibration transmitted to the jumbo lifter 30 during perforation and its change to detect a minute vibration change. The vibration meter 40 does not miss it and adds it up as vibration acceleration.

<B> Detection of punching sound The punching sound generated by the jumbo drifter 30 during punching is
Collected by the sound collecting microphone 12 placed near the face 21,
Sound level meter 5 that does not miss low-pitched punching sound and its changes
Sound pressure is counted as 0.

<C> Data recording The vibration acceleration data and the sound pressure data collected by the vibrometer 40 and the sound level meter 50 are immediately recorded in the data recorder 60.

<D> Data Processing / Analysis The data recorded in the data recorder 60 is transmitted to the frequency analyzer 70, and the face 2 is subjected to the comparison work described below.
Geology in front of 1 (crack a, locally fragile part b, fault crush zone c
Etc.) can be understood.

[Exploration Based on Vibration Acceleration] The vibration of the jumbo drifter 30 generated at the time of perforation, which is collected by the vibrometer 40 via the pickup 11, is recorded as a vibration acceleration in the data recorder 60 at a constant depth. To be done. The data of the vibration acceleration recorded in the data recorder 60 is transmitted to the frequency analyzer 70, the spectrum of 1/3 octave is analyzed in real time, and the vibration acceleration of a plurality of known geological features which has been input as a comparison value in advance. The geological condition at the drilling depth is determined by comparing with the known data. FIG. 3 shows an example of actual measurement data of vibration acceleration at each drilling depth. Each measured data shows an average value measured in 0.5 m units, and in the case of this example, the drilling depth is 2.
The vibration acceleration in the range of 5 m to 3.0 m is the lowest compared to other data, and the drilling depth is 1.0.
It is relatively high in the range of m to 1.5 m compared with other data. The present invention does not judge the geological condition by relatively comparing the data at each depth, but judges the geological condition by comparing with the known data of the vibration acceleration in each geological condition as described above. There are two determination methods: a method of comparing the height difference with known data of vibration acceleration in each quality, and a method of comparison based on the presence or absence of peak data.

[Exploration based on boring sound] Sound collecting microphone 12
The perforation sound of the tunnel face 21 collected by the sound level meter 50 via the is recorded as a sound pressure in the data recorder 60 at each constant depth. The sound pressure data recorded in the data recorder 60 is transmitted to the frequency analyzer 70, and 1 /
The spectrum of 3 octaves is analyzed in real time,
The geological condition at the drilling depth is determined by comparing with the known data of the sound pressures of a plurality of known geological features that have been input in advance as comparison values. FIG. 4 shows an example of actual measurement data of the sound pressure level at each drilling depth. Each actual measurement data shows an average value measured in 0.5 m units, and in the case of this example, the sound pressure level in the range of the drilling depth of 1.5 m to 2.0 m is relatively compared with other data. The lowest and the drilling depth is 0m-0.5
It is relatively high in the range of m compared with other data. The present invention does not judge the geological condition by relatively comparing the data at each depth, but judges the geological condition by comparing with the known data of the sound pressure level in each geological condition as described above. As a judgment method,
There are two methods: a method of comparing the height difference with known data of sound pressure level in each quality, and a method of comparing with the presence or absence of peak data. As shown in FIG. 4, the high frequency part (1.0
(KHz to 10.0 KHz), mechanical noise in the tunnel pit is picked up as noise by the sound collection microphone, making it difficult to read and compare sound pressure levels. Therefore, sound pressure data clearly shows differences in sound pressure levels. It is recommended to use the data in the frequency range that can be confirmed.

[Data Analysis / Analysis] The comparison result of the vibration acceleration change data of the exploration ground and the vibration acceleration comparison data described above and the comparison result of the sound pressure change data of the exploration ground and the sound pressure comparison data are 2 Based on the result of street comparison, the geology of the ground in front of the face is determined. As shown in FIGS. 3 and 4, the change face of the exploration ground and the comparison data prepared separately are analyzed and compared by the frequency analyzer 70, and the face 21
It is possible to understand whether or not there is a crack a, a locally fragile portion b, a fault crush zone c, etc. in the geology ahead.

Explaining in detail, first, the hard ground,
Drilling fragile ground, groundwater or ground containing voids, etc., to obtain comparative data of vibration acceleration and sound pressure. By applying these comparison data to the actual measurement data as shown in FIGS. 3 and 4, and comparing them, the geological condition at each drilling depth is found. In this case, as can be seen from FIGS. 3 and 4, the higher the vibration acceleration and the sound pressure, the harder the perforated ground becomes,
Conversely, the lower the vibration acceleration and sound pressure, the weaker the perforated ground. In addition, Figures 3 and 4 show the comparison of each data.
It shows high-strength rocks and geological weaknesses, but this is a concept for reading data, and originally, relative comparisons are not made in this way, but absolute comparisons with comparison data are made. Understand the state of. As described above, the two geological results determined by the two methods are integrated to finally determine the geological condition at each depth.

[0024]

Second Embodiment In addition to the method described in the first embodiment, only the vibration acceleration by the pickup 11 attached to the punching machine (jumbo lifter 30) is recorded in the data recorder 60, and analyzed and analyzed by the frequency analyzer 70. by doing,
It is also possible to analyze and explore the soil condition ahead.

[0025]

[Third Embodiment] In the first embodiment, it is conceivable to search the soil in front of the ground only by collecting the drilling sound. The forward exploration is performed by collecting the vibration acceleration and the drilling sound described in the first embodiment and analyzing these information.
This is a means for improving the reliability of the analysis result, and basically, it is possible to perform the forward exploration from the vibration acceleration and the drilling sound. In other words, it is possible to analyze and explore the soil condition ahead by using the data that is superior to the soil condition.

[0026]

[Embodiment 4] In any one of Embodiments 1 to 3, it is also conceivable to pick up the peak portion of each obtained data and read the change in geology. Also in this case, the first embodiment
Similarly to the above, the geological condition is read by using each comparison data as a comparison value.

[0027]

Since the present invention is as described above, the following effects can be obtained.

<B> The geology of the tunnel face can be continuously investigated compared with the conventional exploration technique by boring.

<B> By using a normal tunnel construction machine (jumbo drifter), the geology in front of the face can be searched without interrupting the tunnel excavation work.

<C> It is not necessary to install a large device such as an exciter on the face unlike the Rayleigh wave exploration method, and the geology in front of the face can be easily and economically explored.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of tunnel forward exploration technology according to the present invention.

FIG. 2 is an explanatory diagram of a tunnel front exploration method.

FIG. 3 is a conceptual diagram of the relationship between frequency and vibration acceleration data at each drilling depth.

FIG. 4 is a conceptual diagram of the relationship between frequency and sound pressure level data at each drilling depth.

 ─────────────────────────────────────────────────── ─── Continued Front Page (71) Applicant 000201478 Maeda Construction Co., Ltd. 2-1026 Fujimi, Chiyoda-ku, Tokyo (71) Applicant 000166627 Goyo Construction Co., Ltd. 2-2-8 Koraku, Bunkyo-ku, Tokyo No. (72) Inventor Katsuhiko Kato 2-10-2 Otowa, Bunkyo-ku, Tokyo Otowa NS Building 7F, Advanced Construction Technology Center (72) Inventor Jun Mio 1-16-14 Shibuya, Shibuya-ku, Tokyo Tokyu Corporation Incorporated company (72) Inventor Isao Maruyama 3-5-11 Nihonbashihonmachi, Chuo-ku, Tokyo Joint building Omotogumi Co., Ltd. (72) Inventor Masatsugu Suzuki 1-1-13 Yamashita, Okayama City, Okayama Prefecture Company Omoto group (72) Inventor Teruo Sakai 5-8 Takamatsu, Nerima-ku, Tokyo J. CITY Maeda Construction Industry Co., Ltd. (72) Inventor Yutaka Tokunaga 1534-1, Yotsuku, Nishinasuno-cho, Nasu-gun, Tochigi Prefecture Goyo Construction Co., Ltd.

Claims (6)

[Claims] 1. A vibrometer that electrically senses the vibration of a punching tool that punches toward a face, a vibration acceleration of the face that is calculated based on vibration information obtained by the vibrometer, and a known value according to the geology. A tunnel forward exploration device composed of a frequency analyzer for comparison with the comparison data of. 2. A sound collecting microphone that collects the cutting sound of the face, a sound level meter that converts the cutting sound obtained by the sound collecting microphone into sound pressure, and sound pressure information obtained by the sound level meter according to the geology. A tunnel forward exploration device consisting of known comparison data and a frequency analyzer for comparison. 3. A vibrometer that electrically senses the vibration of a punching tool that punches toward a face, a sound collecting microphone that collects the cutting sound of the face, and a sound pressure that cuts the sound obtained by the sound collecting microphone. The vibration acceleration of the face is calculated based on the sound level meter that converts into the sound level and the vibration information obtained by the vibrometer, and the vibration acceleration of the face and the sound pressure information obtained by the sound level meter are compared according to the known geology. A tunnel forward exploration device consisting of a frequency analyzer that compares the data with each other. 4. The cutting face in front of the tunnel is detected after detecting the vibration of a punching tool that punches toward the face and calculating the vibration acceleration of the face based on the vibration information and comparing it with known comparative data according to the geology. A tunnel forward exploration device that seeks geology. 5. A cutting face in front of a tunnel is collected by collecting a cutting sound of a cutting face, converting the cutting sound obtained by the sound collecting microphone into a sound pressure, and comparing the sound pressure information with known comparative data according to geology. A tunnel forward exploration device that seeks geology. 6. The known comparison data according to the geology based on the vibration acceleration information and the sound pressure information, by obtaining the vibration of the punching tool for piercing the face as the vibration acceleration and the cutting noise of the face as the sound pressure. A tunnel forward exploration device that finds the geology of the face in front of the tunnel in comparison with each other.