JP3636998B2 - Sediment movement monitoring system in sediment transport system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sediment movement monitoring system in a sediment transport system.
[0002]
[Prior art]
The sediment transport system is a general term for the entire region where sediment movement occurs from the hillside slope at the uppermost stream of the river to the sand drift region on the coast. In the sand flow system, the entire region is divided into three areas, a hillside slope, a mountain stream / dam, and a river channel, and a sabo dam is provided in the mountain stream / dam area.
[0003]
When it rains on the hillside slope of the uppermost stream of the river, it becomes a debris flow, and the residual sediment accumulates on the upstream side of the sabo dam provided in the mountain stream / dam area. This sedimentary layer thickness is surveyed by human tactics after flooding.
[0004]
Further, it is known that the flood flow and the amount of sediment passing through the mountain stream / dam are grasped by a sediment sediment warning method as disclosed in Japanese Patent Application Laid-Open No. 11-66461, for example. Furthermore, whether or not the riverbed in the river channel area has fallen is determined by stacking multiple colored bricks on the riverbed, for example, and the operator will know the number of bricks that have been washed away from the top later. I knew the amount of decline.
[0005]
[Problems to be solved by the invention]
By the way, since the conventional sediment layer thickness and riverbed decline mentioned above are known at a later date, it was not possible to grasp in time series when the flood occurred. Therefore, it was not enough as a material for taking future measures.
[0006]
Therefore, in the sediment-sand system, the occurrence of sediment-related disasters in hillsides and mountain streams, reduction of sediment supply to downstream rivers due to the construction of dams, river bed degradation caused by gravel collection, etc., safety and usage problems such as coastal erosion, etc. In addition, environmental problems such as the impact on the ecosystem and the loss of beaches are becoming apparent.
[0007]
The present invention has been made to solve the above-mentioned problems, and its purpose is to measure temporal changes in the sediment movement situation in the sediment transport system, and to predict and predict the scale of disasters caused by such movement and deposition, and sabo facilities. The purpose is to provide a sediment movement monitoring system in a sediment transport system that can manage data for the establishment of evaluation technology for sewage.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the sediment movement monitoring system according to claim 1 of the present invention provides a sediment transport system that is an entire region where sediment movement occurs from the hillside slope of the uppermost stream of the river to the drifting area of the coast. The entire area is divided into three areas: mountain slope, mountain stream / dam and river channel. A permeable sabo dam is provided in the mountain stream / dam area, and the sedimentary layer thickness is measured upstream from this permeable sabo dam. In addition to installing a device and a water level measurement device, a flow velocity / flow measurement device that measures the flood flow and the amount of sediment passing through the permeation section is installed downstream from the transmission-type sabo dam. the apparatus is provided, further, there in the earth moving monitoring system in sediment transport system ing provided management device for managing to obtain continuously measured data temporal variations at each measuring device The deposition layer thickness measuring device includes an ultrasonic transmitter / receiver embedded in the riverbed, a controller for controlling the emission of sound waves, an analog recorder for recording reflected waveforms in real time, and data recording for digitally recording measurement data. A river bed lowering measuring device, a sensor unit incorporating a small radio wave transmitter embedded in a river bed in a river channel, and a receiver that receives radio waves transmitted from the sensor unit via an antenna, It is composed of a reception recorder that records the reception situation received by this receiver, and the sensor unit is stacked at a height corresponding to a measurement range targeted by a plurality of sensors downward from the riverbed It is embedded in a state and detachable .
[0009]
Therefore, the sedimentary layer thickness measuring device and the water level measuring device provided on the upstream side of the transmission type sabo dam provided in the mountain stream / dam area measure the sedimentary layer thickness and the water level in the case of flooding, for example. For example, the flood flow rate and the sediment volume at the time of flood are measured by a flow velocity / flow rate measuring device for measuring the flood flow rate and the sediment volume passing through the transmission part provided downstream from the transmission type sabo dam. Further, for example, a river bed drop during a flood is measured by a river bed drop fixing device provided in a river channel area. Further, for example, data measured by each of the measuring devices is sent to a management device provided on the ground and managed. In addition, data measured by each of the measuring devices can be continuously obtained with a temporal change. Furthermore, since each sensor of the sedimentation layer thickness measuring device and the riverbed lowering measurement device is embedded in the riverbed, more accurate sedimentary layer thickness and riverbed degradation can be measured.
[0010]
The sediment movement monitoring system in the sediment transport system according to claim 2 of the present invention is the sediment transport monitoring system in the sediment transport system according to claim 1, wherein a water level measurement device is provided in the vicinity of the flow velocity / flow rate measurement device and the river bed lowering measurement device. It is characterized by.
[0011]
Therefore, the water level is measured by the water level measuring device provided in the vicinity of the flow velocity / flow rate measuring device and the river bed lowering measuring device.
[0012]
The sediment movement monitoring system in the sediment transport system of the present invention according to claim 3 is the sediment transport monitoring system in the sediment transport system of claim 1 or 2 , wherein the water level measuring device is an ultrasonic water level meter. It is.
[0013]
Therefore, a more accurate water level can be obtained when the water level measuring device is an ultrasonic water level gauge.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0015]
Referring to FIG. 1, the sediment transport system is a general term for the entire region where sediment movement occurs from the hillside slope A in the uppermost stream of the river to the sand drift region on the coast B. The entire region in the sand flow system is divided into three areas: a mountain slope A, a mountain stream / dam C, and a river channel D. In the mountain stream / dam C area, a transmission type sabo dam 1 is provided. A sedimentation layer thickness measuring device 3 and an ultrasonic water level meter 5 as a water level measuring device, for example, are provided in the vicinity of the upstream side of the transmission type sabo dam 1 with the transmission type sabo dam 1 as a boundary. Near the downstream of the transmission type sabo dam 1, a flow velocity / flow rate measuring device 7 for measuring the flood flow and the amount of sediment passing through the transmission part is provided. Further, a river bed lowering measuring device 9 is provided in the area of the river channel D. For example, ultrasonic water level gauges 11 and 13 as water level measuring devices are provided in the vicinity of the flow velocity / flow rate measuring device 7 and the river bed lowering measuring device 9. Furthermore, the management apparatus 15 which manages the data measured by each said measuring apparatus is provided, and the earth and sand movement monitoring system 17 is comprised from these each apparatus.
[0016]
As shown in FIGS. 2 and 3, the deposited layer thickness measuring apparatus 3 includes an ultrasonic transmitter / receiver 19 embedded in a river bed, a controller 21 for controlling the emission of sound waves, and a reflected waveform in real time. It comprises an analog recorder 23 for recording and a data recording device (personal computer) 25 for digitally recording measurement data. Moreover, the ultrasonic transmitter / receiver 19 is buried at a position of an assumed fluctuation depth + dead zone 2 m downward from the mud surface on the river bed through sand and gravel. This distance is measured and set in advance as an initial value H0.
[0017]
The ultrasonic transceiver 19 has a frequency of about 6.5 KHz, a directivity angle of 65 degrees, and a maximum input voltage of 500 Vp. p, the outer diameter is 104W * 104D * 178H ± 2 mm, and the controller 21 has a frequency of about 6.5 KHz, a measurement distance of 10 m, and a transmission output of 500 Vp. p, the transmission interval is 1 second, 5 seconds and 10 seconds, the outer diameter is 430 W * 149D * 350H ± 5 mm, and the power supply is AC100V. The data recording device (personal computer) 25 is connected to an initial value / memory 27 for storing the initial value D0 and first and second arithmetic devices 29 and 31.
[0018]
With the above configuration, after the ultrasonic wave is transmitted upward from the ultrasonic transmitter / receiver 19, the reflected wave reflected and returned is received via the controller 21 and is received by the analog recorder 23, for example, as shown in FIG. 4. Reflection occurs because the sedimentary layer recorded as a graph is the boundary between soil and water, and the water surface is the boundary between water, air and medium. As a matter of course, the sound wave reflected in the vicinity of the ultrasonic transmitter / receiver 19 quickly returns, and the far sound wave becomes slow. When this data is processed, it appears strongly on the left side of the graph shown in FIG. 4, and a far object appears weaker on the right side.
[0019]
In FIG. 4, the horizontal axis of the graph indicates the time until sound wave emission returns. This time is expressed as a distance by multiplying the sound speed by 1500 m / sec.
The vertical axis represents the intensity of the sound wave. Sound waves have the property of being reflected at different places in the medium. When expressed in a graph, the leftmost waveform (position indicated by ↓) of the waveform cluster becomes the “change point”, and the subsequent waveform returns with a delay. It is treated as a reflected wave (reverberation). Thus, the leftmost waveform block is the reverberation at the time of sound emission, the next is the riverbed (the boundary between sedimentary layer and water), and the rightmost waveform block is the water surface. .
[0020]
Therefore, a time T1 until the first rise of the second peak from the left in the horizontal axis of the graph shown in FIG. 4 is calculated, and the calculated time T1 is taken into the first arithmetic unit 29. Since the first calculation device 29 has already taken in the sound speed of 1500 m / sec, the first calculation device 29 uses the formula of distance D (m) = sound speed C (m / sec) · propagation time T (sec) / 2. Thus, the actual distance D1 is calculated with D1 = 1500 · T1 / 2. The calculated distance D1 is taken into the second arithmetic unit 31. Since the initial value D0 has already been captured in the second arithmetic unit 31, the second arithmetic unit 31 calculates the deposited layer thickness H1 with H1 = D1−D0.
[0021]
The deposited layer thickness H1 calculated by the second arithmetic unit 31 is calculated every predetermined time, for example, every 60 minutes, and the result is expressed as shown in FIG. 5, for example. In this way, the deposited layer thickness can be obtained continuously with time.
[0022]
As shown in FIG. 6, the ultrasonic water level gauges 5, 11, and 13 serving as the water level measuring device are, for example, ultrasonic waves attached to an arm bar 35 that protrudes upward from the river bed from a pole 33 standing from the riverbank. It comprises a transmitter / receiver 37, a thermometer 39 for correcting the sound speed, a relay box 41 for rearranging the transmission / reception signals, and a converter 43 for calculating the water level from the received signals. Moreover, the ultrasonic transducer 37 is installed at a predetermined height above the reference height (measurement 0 point) of the measurement location. This distance is measured and set as the initial value S0.
[0023]
A signal sent from the converter 43 to the ultrasonic transducer 37 via the relay box 41 is emitted downward, reflected by the water surface, input to the transducer 43 via the ultrasonic transducer 37 and the relay box 41. The A signal from the thermometer 39 for correcting the sound speed is also input to the converter 43 via the relay box 41.
[0024]
In the converter 43, the distance is calculated based on the time returned from the emission of the ultrasonic wave and the temperature information of the thermometer 39, and the result is stored in the converter 43 in advance as the initial value S0. Further subtraction is performed to calculate the height from the reference height (measurement 0 point), that is, the water level.
[0025]
The water level calculated by the converter 43 is calculated every predetermined time, for example, every 60 minutes, and the result is expressed as shown in FIG. 7, for example. In this way, the water level can be obtained continuously over time.
[0026]
As the flow velocity / flow rate measuring device 7, for example, the one shown in JP-A-11-66461 is used. For example, a remote monitoring camera 47 is installed near the upper left side in FIG. 8 of the transmission type sabo dam 1 in a mountain stream / dam C, and a moving image recorder 49 is connected to the remote monitoring camera 47, A workstation 51 is connected to the moving image recorder 49.
[0027]
With the above-described configuration, the remote monitoring camera 47 photographs the basin on the left side of the transmission type sabo dam 1 in the mountain stream / dam C in FIG. The captured video is recorded in a moving image recorder 49 connected to the remote monitoring camera 47 with a video signal cable. The moving picture recorder 49 accumulates continuous moving picture data (30 frames / second) in real time in an uncompressed manner. Since the moving picture recorder 49 is connected to the workstation 51, the moving picture recorder 49 transfers the data at high speed so that the live video can be displayed on the window at a display cycle of 10 to 25 frames / second. The workstation 51 uses a moving image processing package and a water flow analysis package program to extract the speed and surface composition information and alarm output of a debris flow, that is, a solid-liquid multiphase flow in which water flow and rock, rubble, sand, soil, etc. are mixed. Make a decision. In this way, vector analysis is performed on the density movement of the debris flow captured by the fixed remote monitoring camera 47. By calculating the instantaneous velocity level of the local area with continuous moving images and performing statistical processing in the basin, the water level is obtained by the water level meter 11 as shown in FIG. Will be.
[0028]
For example, as shown in FIG. 10, the river bed lowering measuring apparatus 9 includes a sensor unit 53 including a small radio wave transmitter embedded in the river bed in the river channel D, and a radio wave transmitted from the sensor unit 53 with an antenna 55. And a reception recorder 59 for recording the reception status received by the receiver 57.
[0029]
As shown in FIG. 11, the sensor 53 is embedded in a state in which the plurality of sensors 61 are stacked at a height corresponding to a target measurement range (predicted scouring depth) downward from the riverbed. ing. The height of the plurality of sensors 61 is, for example, a length L from the river bed to the lower limit position. The length L is, for example, about 2 to 4 m, and the plurality of sensors 61 is, for example, one set of ten pieces. Therefore, the height of one sensor 61 is set to L / 10.
[0030]
As shown in FIG. 12, the sensor 61 is set with a group number and an ID number indicating an individual number at the time of manufacture. This ID number is not used for both the group represented by the hexadecimal number and the sensor 61. Therefore, the information of the sensor 61 is 1-1, 1-2... 1-F, 2-1 to 2-F,. For example, a single receiver 57 can receive information of 15 * 15 = 175 sensors 61 at the maximum.
[0031]
As shown in FIG. 13, each sensor 61 includes a base 63 having a circular cross section, and transmitters 65 are provided above and below the axial center portion on the base 63. A reed switch 67 is provided in the lower part of the transmitter 65. An outer cylinder 69 is provided on the base 63 so as to surround the transmitter 65. In addition, the outer cylinder 69 and the transmitter 65 are divided into, for example, four parts at equal intervals in the circumferential direction, and a foam material 71 such as foamed polystyrene is inserted into the four divided parts. The reason why the foam material 71 is inserted is that it is divided into four parts, and the buoyancy is maintained even when the sensor 61 hits a rock when the sensor 61 ascends and a part of the outer cylinder 69 breaks down and water enters. One end of a wire 75 is attached to an axial center portion of the outer cylinder 69 via an attachment member 73, and a magnet 77 is provided on the other end of the wire 75. Further, a spacer 79 such as a hollow paper tube is attached below the axial center portion of the base 63, and the height of each sensor 61 is adjusted by the height of the spacer 79. Yes. In addition, a case 81 for housing the magnet 77 is provided inside the spacer 79. A magnet 77 is housed in the case 81 and is attracted to the base 63. The reed switch 67 is not energized, and in this state, the reed switch 67 is OFF.
[0032]
With the above configuration, for example, ten sensors 61 are stacked, and when a flood occurs and the riverbed is swept away, the uppermost sensor 61 is shown in FIG. To be removed. That is, when the magnet 77 in the second sensor 61 is removed from the first sensor 61, the first sensor 61 is in a floating state and the reed switch 67 of the first sensor 61 is OFF ( The radio wave transmitted from the first sensor 61 is received by the receiver 57 via the antenna 55 and then received and recorded in the reception recorder 59. . That is, the reception time and the ID number of the sensor 61 are printed and recorded. Even when there is no transmission from the sensor 61, the regular printing is performed once per hour. The data received and recorded in the reception recorder 59 is as shown in FIG. In FIG. 14, for example, the water level measured by the ultrasonic water level gauge 13 is also shown.
[0033]
In this way, it is possible to automatically measure the riverbed drop every moment according to the change of time.
[0034]
Therefore, each data measured by the deposition layer thickness measuring device 3, the flow velocity / flow rate measuring device 7, the river bed lowering measuring device 9 and the ultrasonic water level gauges 5, 11, 13 is sent to the management device 15, whereby each of the above measurements. Each data measured by the apparatus can be managed. Thus, it is possible to grasp the sediment movement situation in the sediment transport system in time series. In other words, it is possible to measure temporal changes in the sediment movement situation in the sediment transport system, and to provide data for predicting and predicting the scale of disasters caused by those movements and accumulations, and establishing evaluation techniques for sabo facilities.
[0035]
In addition, this invention is not limited to embodiment mentioned above, It can implement in another aspect by making an appropriate change.
[0036]
【The invention's effect】
As can be understood from the description of the embodiment of the invention as described above, according to the invention of claim 1, the deposition provided on the upstream side with respect to the transmission type sabo dam provided in the area of the mountain stream / dam. Sediment thickness and water level can be measured by a layer thickness measuring device and a water level measuring device, for example, during floods, and at the downstream of a transmission type sabo dam For example, it is possible to measure the flood flow rate and the amount of earth and sand during a flood by using a flow velocity / flow rate measuring device that measures the amount. Further, for example, a river bed drop during a flood can be measured by a river bed drop fixing device provided in a river channel area. Further, for example, data measured by each of the measuring devices can be sent to a management device provided on the ground to manage each data.
[0037]
Data measured by each of the measuring devices can be obtained continuously with time. Thus, it is possible to measure the temporal change of the sediment movement situation in the sediment transport system, and manage the data for the prediction and prediction of the disaster scale caused by the movement and accumulation, the establishment of the evaluation technology for the sabo facilities, and the like.
Thus, it is possible to grasp the situation of sediment movement in the sand flow system.
[0038]
According to the invention of claim 2, the water level can be measured by the water level measuring device provided in the vicinity of the flow velocity / flow rate measuring device and the river bed lowering measuring device.
[0039]
Thus, it is possible to grasp the sediment movement status in the sediment transport system by taking into account the water level measured by the water level measuring device provided in the vicinity of the flow velocity / flow rate measuring device and the river bed lowering measuring device.
[0040]
According to the invention of claim 3 , since the water level measuring device is an ultrasonic water level gauge, a more accurate water level can be obtained.
[Brief description of the drawings]
FIG. 1 is a diagram showing an entire sediment movement monitoring system in a sediment transport system.
FIG. 2 is a view showing a deposited layer thickness measuring apparatus.
FIG. 3 is an explanatory diagram of a state in which an ultrasonic transmitter / receiver of the deposition layer thickness measurement device is embedded in a river bed.
FIG. 4 is a diagram showing an example of a graph acquired by a data acquisition device of a deposition layer thickness measurement device.
FIG. 5 is a diagram showing an example of a graph recorded by the data acquisition device of the deposition layer thickness measurement device.
FIG. 6 is a diagram showing each ultrasonic water level meter.
FIG. 7 is a diagram showing an example of a graph measured by an analog recorder of each ultrasonic water level meter.
FIG. 8 is a view showing a flow rate / sediment amount measuring apparatus.
FIG. 9 is a diagram showing an example of a graph measured at a workstation of the flow rate / sediment amount measuring apparatus.
FIG. 10 is a diagram showing a river bed lowering measuring apparatus.
FIG. 11 is an explanatory diagram of a state in which each sensor of the sensor unit is stacked and embedded in the river bed.
FIG. 12 is a diagram showing a measurement block measured by each sensor.
FIG. 13 is a diagram showing the structure of a sensor.
FIG. 14 is a diagram showing an example of a graph received and recorded by the reception recorder of the river bed lowering measuring device and an example of a graph recorded by the data acquisition device of the water level meter.
[Explanation of symbols]
1 Transmission Sabo Dam 3 Sediment Layer Thickness Measurement Device 5 Ultrasonic Water Level Meter (Ultrasonic Measurement Device)
7 Flow rate / sediment volume measuring device 9 River bed drop measuring device 11, 13 Ultrasonic water level meter (water level measuring device)
15 Management Device 17 Sediment Movement Monitoring System 19, 33 Ultrasonic Transmitter / Receiver 21, 35 Controller 23, 37 Analog Recorder 25, 39 Data Acquisition Device 27, 41 Initial Value / Memory 29, 43 First Computing Unit 31, 45 First 2 arithmetic unit 47 remote monitoring camera 49 video recorder 51 workstation 53 sensor unit 55 antenna 57 receiver 61 sensor 63 base 65 transmitter 67 reed switch 69 outer cylinder 71 foam material 73 mounting member 75 wire 77 magnet 79 spacer

Claims (3)

In the sediment transport system, which is the entire area where sediment movement occurs from the hillside slope of the uppermost stream of the river to the sand drifting area on the coast, divide this entire area into three areas: hillside slope, mountain stream / dam and river channel. A transmission-type sabo dam is provided in this area, and a sedimentation layer thickness measurement device and a water level measurement device are provided upstream from this transmission-type sabo dam. A flow velocity / flow rate measuring device that measures the amount of sediment passing through the permeation part is provided, and a river bed lowering measuring device is provided in the river channel area, and the data measured by each measuring device is continuously changed over time. a soil movement monitoring system in sediment transport system ing to the management device provided for managing to obtain,
The deposition layer thickness measuring device includes an ultrasonic transmitter / receiver embedded in a river bed, a controller for controlling the emission of sound waves, an analog recorder for recording reflected waveforms in real time, and a data recording device for digitally recording measurement data The riverbed lowering measuring device comprises a sensor unit incorporating a small radio wave transmitter embedded in the riverbed in a river channel, a receiver for receiving radio waves transmitted from the sensor unit via an antenna, It is composed of a reception recorder that records the reception status received by the receiver, and the sensor section is stacked at a height corresponding to the measurement range targeted by a plurality of sensors downward from the riverbed Sand movement monitoring system characterized by being embedded in a removable manner .   2. The sediment movement monitoring system in a sand flow system according to claim 1, wherein a water level measuring device is provided in the vicinity of the flow velocity / flow rate measuring device and the river bed lowering measuring device. 3. The sediment movement monitoring system in a sand flow system according to claim 1, wherein the water level measuring device is an ultrasonic water level meter.

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