JP7157414B2 - Tunnel face safety monitoring system and tunnel face safety monitoring method - Google Patents

Description

The present invention relates to a tunnel face safety monitoring system and a tunnel face safety monitoring method.

Conventionally, the NATM (New Austrian Tunneling Method) construction method, which enables geological surveys by observing the face, is often used as a method for excavating mountain tunnels because it can predict the geological features ahead to some extent in combination with surveys such as advanced boring. ing.
On the other hand, in the construction of a mountain tunnel by the NATM construction method, the natural ground in the face region is almost exposed from immediately after blasting (or mechanical excavation) to secondary concrete spraying.

For example, when excavating a tunnel, it is necessary to erect shoring (a temporary structure used to support the load) in order to support the load from above or from the side of the tunnel.
When erecting this shoring, workers have no choice but to approach the face, and workers are forced to erect under conditions where there is danger such as the collapse of the face (more precisely, the face surface). Become.

In addition, as the working population in the construction industry has decreased in recent years, we are actively using ICT (Information and Communication Technology) technology in tunnel construction as well. Promotion of computerization (information-oriented construction) is required.
Furthermore, in terms of safety management at construction sites, there is a demand for a safer management method for the condition of the face in the construction of mountain tunnels by utilizing ICT technology.

In mountain tunnel construction, as a measure to prevent falling rocks and the like from the face surface where the above-mentioned tunnel is excavated, there is displacement measurement of the face surface for predicting the occurrence of the falling surface.
That is, the temporal displacement of the face of the tunnel is measured by a measuring device, and minute displacement of the face that cannot be visually confirmed by the operator is detected.
Then, the person in charge of face monitoring can predict the occurrence of falling skin by detecting a minute displacement with a measuring device, and the accuracy of monitoring of collapse can be improved.

Regarding the above-mentioned displacement measurement of the face, a laser displacement measuring device is used to measure the displacement of the face of the tunnel, and when a predetermined displacement is detected on the face in the measurement result, a tunnel collapse prediction that outputs an alarm There is a method (see Patent Document 1, for example).
In this method, by using a laser scanner, displacement measurement at many positions on the face can be performed in one scan.

On the other hand, using an image processing technique, it is possible to detect a moving object such as a very small falling rock from the face from the captured image of the face from the color change accompanying the state change due to the displacement. Further, by combining the detection of a moving object on the face of the face by this image processing technology with the displacement measurement described above, it is possible to further improve the accuracy of monitoring the collapse of the face.

JP-A-09-287948

However, as in Cited Document 1, when a laser displacement measuring device is used to measure the displacement of the face, one laser displacement measuring device measures the displacement at one point on the face. Therefore, in order to collectively detect the displacement of the entire face, a large number of laser displacement measuring instruments are required, and it is difficult to detect the displacement of the face.

Moreover, in order to detect the displacement as a plane with one laser displacement measuring instrument, it is necessary to change the radiation angle of the laser light in the horizontal direction and the vertical direction. In order to change the direction of the laser beam exit port of the laser displacement measuring instrument in the horizontal and vertical directions, there is also a configuration in which the laser displacement measuring instrument is mounted on a stand having an angle changing mechanism capable of rotating in the horizontal and vertical directions. . Accordingly, there is a configuration in which many points on the face are measured while changing the radiation angle by the angle changing mechanism so that the laser beam of the laser displacement measuring device is irradiated to different positions on the face.

When measuring the displacement of the laser beam radiation angle with an angle changing mechanism, it takes a lot of time to scan the entire face surface, and the displacement state is measured in real time with the entire face surface as one surface. Can not do it. In addition, in the case of displacement measurement using a laser scanner, equipment capable of real-time measurement has been developed, but the displacement measurement accuracy is cm units, which is the accuracy required to predict the collapse of the face surface. Displacement in mm units cannot be detected.
When detecting moving objects such as falling rocks using image processing technology, the detection of falling rocks indicates the possibility that rock masses that collapse at the face are moving. Therefore, even if the face collapses at any time, it will not be detected unless it is in a good state, and it cannot be used as data for prediction.

The present invention has been made in consideration of the above circumstances. It is an object of the present invention to provide a tunnel face safety monitoring system and a tunnel face safety monitoring method.

In order to solve the above problems, the tunnel face safety monitoring system of the present invention is a tunnel face safety monitoring system that monitors the state of the face of a tunnel to be excavated, and the entire surface of the face is included in the irradiation range of the measurement beam. Detect the displacement amount, displacement speed, frequency, and amplitude of the entire face surface of the face surface from the measurement result of the reflected beam for the measurement beam from the face surface and the real aperture radar by the antenna multi-beam arranged in and a displacement detection server.

The tunnel face safety monitoring method of the present invention is a tunnel face safety monitoring method for monitoring the state of the face of a tunnel that is being excavated, and the antenna multiple beams are arranged at a position where the entire surface of the face is included in the irradiation range of the measurement beam. From the process of radiating the measurement beam from the real aperture radar and the measurement result of the reflected beam from the measurement beam from the face surface, the displacement amount, displacement speed, frequency, and amplitude of the entire face surface of the face face are detected. and the step of

According to the present invention, the tunnel face safety monitoring system uses the entire face as one measurement plane and detects the displacement state of this measurement plane in real time with accuracy to the extent that a collapse on the face can be predicted. And a tunnel face safety monitoring method can be provided.

1 is a conceptual diagram showing the inside of a tunnel in which the tunnel face safety monitoring system of this embodiment is arranged; FIG. FIG. 4 is a plan view of the tunnel viewed from above, explaining the arrangement of the vibration visualization radar. FIG. 2 is a conceptual diagram showing a cross-section of a tunnel illustrating the installation of a vibration visualization radar on the side walls of the tunnel; FIG. 4 is a diagram for explaining a coordinate system for observing the measurement result of the face and the vibration and displacement of the face; FIG. 4 is a diagram illustrating vibration and displacement at each observation point on the face in the face coordinate system;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following example, a case of excavating a tunnel by NATM (New Austrian Tunneling Method) will be described. After excavating the cross section of the tunnel using blasting or machinery, NATM removes the dirt by transporting the excavated earth, sand, and rocks, installs shoring, and sprays concrete on the walls and ceiling. Drive rock bolts from the ground toward the ground. Then, sheets are installed inside the tunnel for waterproofing, formwork is constructed, concrete is poured and concrete lining is performed, and the tunnel is finished. It should be noted that the present invention is not limited to excavating tunnels using NATM.

An embodiment of a tunnel face safety monitoring system according to the present invention will be described below with reference to FIG. FIG. 1 is a conceptual diagram showing the inside of a tunnel in which the tunnel face safety monitoring system of this embodiment is installed. In FIG. 1, each of vibration visualization radars 21 and 22 is provided for monitoring the condition of the face 15 in the tunnel 10 . The face 15 is an observation target of each of the vibration visualization radars 21 and 22 .

Each of the vibration visualization radars 21 and 22 radiates a radio wave of a predetermined frequency to the entire surface of the face 15 as a measurement beam, and measures the reflected beam from the surface of the face 15 .
The measurement control server 40 is, for example, a personal computer, acquires reflected beam data from each of the vibration visualization radars 21 and 22 , and measures vibration and displacement on the entire surface of the face 15 . In addition, the measurement control server 40, when each of the vibration and displacement of the surface of the face 15 exceeds the respectively set vibration threshold (also amplitude threshold) and displacement threshold, the warning notification device 51 such as a warning light, , a warning signal is transmitted to a mobile terminal 52 such as a smart phone carried by a worker 30 (an operator of a construction machine (excavation machine) used for excavation, an underground worker, or the like).

For example, in the case of a warning light, the warning notification device 51 notifies the worker 30 to move away from the face 15 by flashing a red light along with a sound indicating evacuation. In addition, the portable terminal 52 sounds an evacuation sound or an alarm using an installed warning application to notify the worker 30 to move away from the face 15 .
In addition, the measurement control server 40 sends a warning signal via the wireless router 60 to a terminal 71 such as a personal computer installed in a management center 70 of a field station or field office, and a warning notification device 72 such as a warning light. to send. Data transmission/reception between the measurement control server 40 and each of the warning notification device 51, the terminal 71, and the warning notification device 72 may be performed wirelessly or by wire. In addition, a configuration may be adopted in which a danger signal or an image showing the condition of the face surface in the face surface coordinate system is transmitted to a terminal of a department related to the excavation work other than the tunnel excavation work site via an Internet line or the like.

As described above, the tunnel face safety monitoring system according to this embodiment uses the vibration visualization radars 21 and 22 to quickly (almost Simultaneous, that is, real-time) detection is performed to detect in advance signs of loosening of the natural ground at the face 15 of the tunnel during face work and signs of collapse. The tunnel face safety monitoring system includes at least each of vibration visualization radars 21 and 22 and a measurement control server 40 .

In general, in the NATM construction method, construction of tunnels in mountains consists of "blasting drilling" to form a hole for inserting explosives, "charge" to the drilled hole, "Kokoku" is used to drop rocks that are likely to collapse due to loosening of the ground on the excavation surface using an iron bar. "Facing observation" is to observe the condition of the face. "Primary shotcrete" to be constructed, "Steel shoring erection" to erect steel shoring on the inner surface of the tunnel, Wire mesh is installed on the back of the steel shoring, and the second shotcrete A series of processes such as "secondary shotcrete" to construct the tunnel and "rock bolt driving" to drive rock bolts radially from the inner surface of the tunnel are repeated. In this embodiment, in an excavation cycle in which each of the steps described above is repeated, the entire surface of the face 15 is continuously monitored for each step in the excavation cycle.

FIG. 2 is a plan view of the tunnel viewed from above, explaining the placement of the vibration visualization radar. FIG. 2 shows a tunnel pit in which a drill jumbo 80 is located as an example of a drilling machine. In the following description, "forward" indicates the direction of the face 15A, and "rearward" indicates the direction of the entrance of the tunnel 10. As shown in FIG. The vibration visualization radar 21 is installed on the left side wall 10L of the tunnel 10, for example, in a range of 10 m to 20 m rearward from the face 15A. The vibration visualization radar 22 is installed on the right side wall 10R of the tunnel 10, for example, in a range of 10 m to 20 m behind the face 15A. Also, the measurement control server 40 is installed, for example, about 10 m behind the vibration visualization radar 21 .

As shown in FIG. 2, when using the two vibration visualization radars 21 and 22 at the same time, when using measurement beams (radio waves) of the same frequency, when receiving the reflected beam, There is a risk of receiving the measurement beam itself of the visualization radar or the reflected beam that is the reflected wave of the measurement beam. Therefore, in order to prevent radio wave interference between different vibration visualization radars, it is necessary to differentiate the frequencies of the measurement beams emitted by each of the plurality of vibration visualization radars.

FIG. 2( a ) shows a state in which a part of the measurement beam of the vibration visualization radar 21 is blocked by a protruding object 81 such as a drill or deck of the drill jumbo 80 . FIG. 2B shows a state in which the projection 81 of the drill jumbo 80 partially shields the measurement beam of the vibration visualization radar 22 . In this embodiment, a drilling apparatus such as a drill jumbo 80 used for excavating a tunnel does not block the measurement beam and the vibration and displacement at any position on the face surface 15A cannot be detected. Observation of the face 15A of the tunnel 10 is performed using the vibration visualization radar on the platform. In addition, if there is no obstruction between the vibration visualization radar and the face and the measurement beam is not blocked, it is possible to operate the tunnel face safety monitoring system with only one vibration visualization radar. .

FIG. 3 is a conceptual diagram showing a cross-section of a tunnel, illustrating the installation of the vibration visualization radar on the sidewall of the tunnel. FIG. 3(a) shows that a steel shoring (or shoring) 10_1 is attached with a placement base 91 by a mounting jig 92 and fixed, and this placement base 91 is attached to a vibration visualization radar 21 by a support member 93. It shows an example of reinforcing to a strength that can withstand the load of . FIG. 3(b) shows that a placement base 91 is attached by a mounting jig 94 to a concrete layer 10_2 formed on the inner peripheral surface of a tunnel by each of primary shotcrete and secondary shotcrete, and this An example is shown in which the placement table 91 is suspended and fixed by a suspension member 95 and reinforced to a strength capable of withstanding the load of the vibration visualization radar 21 . The suspension member 95 has one end connected to the placement base 91 and the other end connected to the head portion 101B of the lock bolt 101 . Also, the configuration of installation of each of the vibration visualization radar 22 and the measurement control server 40 is the same as the configuration described above.

Further, when the vibration visualization radar 21 (or the vibration visualization radar 22) is installed on the placement table 91 as described above, the vibration visualization radar 21 is installed so that the distances to each observation point on the face 15A of the tunnel 10 are different. Install. In other words, in terms of the principle of radar measurement, it is impossible to distinguish between these two points by simultaneously receiving reflected beams, which are reflections of the measurement beams at the object of observation equidistant from the radar. Therefore, the vibration visualization radar 21 is installed in the vicinity of the bottom of the tunnel on the left wall 10L behind the face 15A so that the distances between the vibration visualization radar 21 and each observation point on the face 15A are different (distance differences occur). Thus, the vibration visualization radar 21 is installed so that the measurement beam is radiated from the bottom (tunnel bottom) to the top (tunnel top) with respect to the face surface 15A.
Also, it is installed in the region of the left side wall 10L in the vicinity of the top of the tunnel behind the face 15A. Accordingly, the vibration visualization radar 21 may be installed so that the measurement beam is radiated from the top (tunnel top) to the bottom (tunnel bottom) with respect to the face surface 15A.

Further, in the present embodiment, the configuration in which the vibration visualization radar is installed on the shoring has been described. It may be installed at a position where the face of the construction machine used for construction can be observed, or it may be configured as a special vehicle that moves with a vibration visualization radar mounted.
In addition, in the present embodiment, the configuration of two vibration visualization radars 21 and 22 has been described, but the number is not limited to two. , the face collapse may be predicted with high accuracy.

The monitoring control of the face 15A by the measurement control server 40 using the vibration visualization radars 21 and 22 will be described below.
Each of the vibration visualization radars 21 and 22 in the present embodiment is a real aperture radar with multiple antenna beams using DBF (Digital Beamforming) technology. Control of the vibration visualization radar 21 will be described below as an example.
The measurement control server 40 controls the vibration visualization radar 21 to radiate measurement beams from each of the plurality of antennas at predetermined measurement intervals. Then, the measurement control server 40 reads the measurement data of the face 15A in the radar coordinate system from the vibration visualization radar 21 .

FIG. 4 is a diagram for explaining the coordinate system used when observing the measurement result of the face and the vibration and displacement of the face. FIG. 4(a) shows a radar coordinate system showing measurement results of the vibration visualization radar. The radar coordinate system consists of two axes, the position determined by the range distance in the range direction and the cross-range angle in the cross-range direction. and scattering intensity are recorded as complex amplitude data.
On the other hand, FIG. 4(b) shows the face plane coordinate system when observing the vibration and displacement of the face plane. This face plane coordinate system indicates the coordinate values in the spatial coordinates of each observation point on the face plane 15A, which are obtained from the range distance and the cross range angle and the phase difference. In FIG. 4B, the face surface data in the face surface coordinate system is represented by the coordinate values on the two-dimensional plane 15H consisting of the X axis and the Y axis of the position of each observation point on the face surface 15A, and each observation point (height data z) indicating the unevenness of the face surface 15A in is indicated by the Z-axis.
That is, the measurement control server 40 performs a process of converting the radar coordinate system into a face coordinate system indicating height data at each observation point on the face 15A.

FIG. 5 is a diagram illustrating vibration and displacement at each observation point on the face in the face coordinate system. FIG. 5A shows grid pixels 200 as observation points on the face 15A in a two-dimensional coordinate system consisting of the X-axis and the Y-axis in the face coordinate system. The height data z indicates the coordinates of each grid pixel 200 on the face 15A with respect to the Z-axis direction. Then, the measurement control server 40 writes and stores the face surface data in the face surface coordinate system in the internal storage unit for each measurement cycle.

FIG. 5(b) is a diagram showing how to obtain the displacement Δd of the lattice-like pixels 200 on the face surface 15A of the measurement control server 40. As shown in FIG. According to the principle of radar, the distance between the radar and the grid pixels 200 can be obtained from the difference between the time when the radio wave is emitted from the transmitting antenna and the time when the radio wave reflected (scattered) from each pixel is received by the receiving antenna. can. On the other hand, the difference between the phase differences (φ1, φ2) between the transmission wave and the reception wave obtained by the (n−1)-th and n-th measurements corresponds to the displacement of the grid pixel 200 .
Using these (φ1, φ2), in the grid pixel 200 having the same coordinate values (x, y) in the two-dimensional coordinate system, from the n-th height data zn to the (n-1)-th height data zn- By subtracting 1, the displacement Δd of the grid-like pixel 200 can be obtained by comparing the height data of the grid-like pixel 200 in the (n−1)th measurement cycle and the n-th measurement cycle.

As a result, by comparing the height data zt0 in the face data of the initial measurement period t0 with the height ztn in the face data of the predetermined measurement period, the initial measurement period of each observation point on the face 15A can be obtained. A displacement .DELTA.d (ztn-zt0) generated in a predetermined measurement period tn from t0 is obtained. The measurement control server 40 also obtains the period of vibration of the face 15A by obtaining the displacement Δd for each adjacent measurement period and observing the displacement over time.

The measurement control server 40 successively compares the height data zt0 of the initial measurement period t0 with the height data ztn of the most recent measurement period, and issues a warning when the preset displacement threshold and displacement speed threshold are exceeded. A signal is output to each of the warning notification device 51 and the portable terminal 52 . In addition, the measurement control server 40 arranges the changes in the displacement Δd between the measurement periods from the initial measurement period t0 to the most recent measurement period in chronological order, and interpolates the displacement Δd between the measurement periods to form the curve. Graph and obtain the frequency (frequency of vibration) and amplitude value of this curve, if the frequency exceeds the preset frequency threshold, or (and) the amplitude of the curve exceeds the preset amplitude threshold In this case, a warning signal is output to each of the warning notification device 51 and the portable terminal 52 .

The above-described displacement threshold, displacement velocity threshold, frequency threshold, and amplitude threshold are thresholds for evaluation indices (displacement amount, displacement velocity, frequency, amplitude) used for detecting a sign of a face collapse (prediction of a face collapse). This evaluation index is divided into two types: when vibration is applied (drilling, drilling, drilling, steel shoring installation, rock bolting, etc.) and when no vibration is applied. Set separately for excitation (charger, face observation, primary and secondary shotcrete, etc.). For example, at the time of drilling vibration for forming a blasting hole, mainly the vibration characteristics (vibration frequency and amplitude) of the face surface 15A are used as an evaluation index. Specifically, the possibility of face collapse is determined based on changes in the dominant frequency (frequency), cumulative amplitude (amplitude), and the like. On the other hand, when there is no vibration such as charging and observation of the face, mainly the displacement amount and the displacement speed of the face 15A are used as evaluation indexes. The possibility of a face collapse is determined based on the amount of displacement Δd described above and the increase or decrease in displacement speed. The measurement control server 40 notifies the warning notification device 51 and the portable terminal 52 that the face 15 is in a dangerous state when each of the evaluation indexes described above exceeds a predetermined threshold. do.

Here, the predetermined threshold value, which is the reference value of the evaluation index for predicting collapse, differs depending on the nature of the ground. Regarding the reference value, it is appropriate to measure the displacement behavior in the face during excavation work and accumulate the data on the collapse phenomenon to set it. However, in the case of rocks where sufficient data on collapse phenomena have not been accumulated, the measurement data of face collapses observed in other rocks in the past and the instability measured on bedrock slopes It is also possible to set an appropriate reference value in consideration of the geological conditions of the tunnel site of the natural ground, etc., by referring to the vibration characteristic data of rock masses or experimental examples related to the prediction of collapse of rock masses.
In addition, it is also possible to accumulate basic data by conducting experiments simulating the skin falling phenomenon on the face surface and analytical examination by computer simulation, etc., and reflect it in setting the standard value of the evaluation index for predicting face collapse. be.

As described above, according to this embodiment, in tunnel excavation in natural ground, the entire face surface of the tunnel is used as one measurement surface, and the displacement state (displacement amount, displacement speed, vibration frequency , amplitude) can be detected in real time with an accuracy sufficient to predict face collapse.
That is, according to this embodiment, the face surface in excavation of the tunnel is one surface, and the states such as displacement and vibration of each of a plurality of observation points (multiple points) on this surface are continuously measured at a predetermined cycle ( By measuring in chronological order), the measurement results are compared with each evaluation index, so it is possible to estimate the loosened state of rock masses, sediment, etc. It is possible to detect (or presume) at a high level, and the safety of work in the vicinity of the working face can be improved.

In addition, according to this embodiment, since the face surface is monitored by two or more vibration visualization radars, even if there is a vibration visualization radar whose measurement beam or reflected beam is blocked by the construction machine, other vibration visualization radars It is possible to supplement with radar measurement beams and reflected beams, and it is possible to suppress the range of the area where measurement is impossible to the minimum, and to detect signs of collapse of the face surface reliably with high accuracy. .
In addition, according to the present embodiment, by using a vibration visualization radar that emits a measurement beam as a millimeter-wave radio wave, the spatial resolution on the face surface is approximately 5 cm (a lattice-like observation in FIG. 5A). It is possible to improve the resolution of observation points on the face surface. can be detected.

In addition, according to this embodiment, when the evaluation index for predicting the collapse of the face surface exceeds a predetermined threshold value, a danger signal is sent to inform the operator of the danger, so an accident due to the collapse of the face occurs. It is possible to quickly implement preventative measures and criticize workers before the construction of tunnels, which enables safe tunnel construction.
In addition, according to this embodiment, since the vibration visualization radar is attached to the shoring behind the face, movement of construction machines and transportation machines used for tunnel construction, various piping and wiring in the tunnel, etc. As long as it does not interfere with the installation of equipment, etc. and is within a distance that can be measured by the vibration visualization radar, there is no need to move the vibration visualization radar along with the progress of the tunnel face, and the tunnel including the vibration visualization radar It is possible to omit the time and manpower required to install each device of the face safety monitoring system.

In addition, according to the present embodiment, since the observation work of the face surface by the vibration visualization radar is controlled by the program set in advance using the measurement control server, the state of the face surface can be observed with high accuracy in a short time. Since the measurement results can be displayed immediately, there is no need to temporarily stop tunnel construction to observe the face surface or measure the condition, and the construction period for tunnel excavation is not affected.
In addition, according to the present embodiment, by storing the measurement data obtained by the measurement control server in the observation of the face surface as electronic data in a database or the like, the face surface can be used for tunnel construction on other natural grounds to be performed later. It will be possible to use it as basic data that contributes to improving the accuracy of prediction of collapses.

It should be noted that a program for realizing the functions of the measurement control server 40 of FIG. 1 in the present invention may be recorded in a computer-readable recording medium, and the program recorded in this recording medium may be read and executed by a computer system. Therefore, observation of the state of the face during tunnel construction may be performed using the measurement values of the vibration visualization radar, and prediction processing of collapse of the face may be performed. It should be noted that the "computer system" referred to here includes hardware such as an OS (Operating System) and peripheral devices. Also, the "computer system" includes a WWW (World Wide Web) system provided with a homepage providing environment (or display environment). In addition, "computer-readable recording medium" refers to portable media such as flexible discs, magneto-optical discs, ROM (Read Only Memory), CD-ROM (Compact Disc - Read Only Memory), etc. A storage device such as a hard disk. In addition, "computer-readable recording medium" means the volatile memory (RAM (Random Access Memory)), which holds programs for a certain period of time.

Further, the above program may be transmitted from a computer system storing this program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in a transmission medium. Here, the "transmission medium" for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. Further, the program may be for realizing part of the functions described above. Further, it may be a so-called difference file (difference program) that can realize the above-described functions in combination with a program already recorded in the computer system.

21,22...Vibration visualization radar 30...Worker 40...Measurement control server 51,72...Warning notification device 52...Mobile terminal 71...Terminal

Claims (9)

A tunnel face safety monitoring system that monitors the state of the face of a tunnel to be excavated,
a real aperture radar with multiple antenna beams arranged at a position where the entire surface of the face is included in the irradiation range of the measurement beam;
a displacement detection server that detects the displacement amount, displacement speed, frequency, and amplitude of the entire surface of the face from measurement results of the reflected beam from the face of the face with respect to the measurement beam. Monitoring system. 2. The tunnel face safety monitoring system according to claim 1, wherein a plurality of said real aperture radars are provided on the inner peripheral surface of said tunnel capable of irradiating said measurement beam onto said face. The displacement detection server
When synthesizing and generating a face surface coordinate system indicating unevenness at each predetermined position of the face surface generated from the radar coordinate systems of the plurality of real aperture radars, the 3. The tunnel face safety monitoring system according to claim 2, wherein areas where the measurement beam is blocked by a machine and lacked are complemented by other radar coordinate systems and synthesized. The tunnel face safety monitoring system according to claim 2 or 3, wherein radio waves of different frequencies are used for each of said measurement beams radiated by said real aperture radar. The actual aperture radar is a first actual aperture radar and a second actual aperture radar, which are provided on left and right side walls of the tunnel, respectively, and the radiation direction of the measurement beam is directed toward the face surface, which is the face surface. The tunnel face safety monitoring system according to any one of claims 1 to 4, wherein the tunnel face safety monitoring system is characterized by: 6. The real aperture radar is provided on a mounting member fixed to a shoring in the vicinity of the face face provided inside the tunnel of the tunnel. The tunnel face safety monitoring system described in . 7. The tunnel face safety monitoring system according to claim 6, wherein the mounting member is a placement base suspended from a hanging member attached to the head of the lock bolt. The tunnel face according to any one of claims 1 to 7, wherein the real aperture radar is arranged so that the radiation direction of the measurement beam has a predetermined angle with respect to the face. Safety monitoring system. A tunnel face safety monitoring method for monitoring the state of the face of a tunnel to be excavated,
a process of radiating the measurement beam from a real aperture radar with multiple antenna beams arranged at a position where the entire surface of the face is included in the irradiation range of the measurement beam;
and detecting a displacement amount, displacement velocity, frequency, and amplitude of the entire surface of the face from measurement results of a beam reflected from the face of the face with respect to the measurement beam. .

Images