JP4932198B2 - Sediment measuring device - Google Patents

Description

  The present invention relates to a sediment measuring device for measuring sediment such as scavenging sand.

  In recent years, sediment dynamics in river basins have changed greatly due to various anthropogenic environmental loads on water systems. In order to cope with this, it is pointed out that there is a need for integrated sediment management in the water system that comprehensively manages sediment dynamics from the source of the river to the mouth and sea area. In that case, it is necessary to conduct extensive and accurate surveys of sediment dynamics in the river channel, which is the basis of sediment management.

  Sediment dynamics survey includes measurement of floating sand volume and wash load, and measurement of sediment flow.

  For the measurement of floating sand amount and wash load, a direct method of collecting water containing earth and sand and an indirect method using characteristics such as light and ultrasonic waves are used. The direct method is a method of collecting river water with a bucket or a pump. The indirect method is measured using an optical turbidimeter based on light transmittance or scattering intensity, an ultrasonic velocimeter utilizing the correlation between ultrasonic reflection intensity and sediment concentration, or the like. For measurement of suspended sand and wash load, automatic and continuous measurement over a long period of time is possible by using these methods and their combinations.

On the other hand, a direct method for measuring the volume and weight of earth and sand and an indirect method using sound or the like are used for the measurement method related to the amount of sand flow. As a direct method, there is known a method for automatically and continuously measuring the amount of the swept sand by collecting the swept sand with a collector installed on the river bed surface or in the river bed, and measuring the mass of the collected sand using a load meter. (For example, refer to Patent Document 1). As an indirect method, an acoustic method (hydrophone) that measures the sound and vibration of gravel that collides with an iron plate or an iron pipe installed on the riverbed is known.
JP-A-3-154830

  However, the conventional measuring device for measuring the amount of scavenging sand is larger than the measuring device for floating sand amount and wash load, so it cannot be measured easily, and the price of the device is expensive. There were many.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an earth and sand measuring apparatus that can easily and easily measure earth and sand such as sweeping sand.

To achieve the above object, the earth and sand measuring device of the present invention includes a box having an opening and a receiving part housed in the box so as to receive and discharge the earth and sand flowing from the opening of the box. A falling mass that includes a pair of masses, is supported in the box so as to be able to fall according to the amount of earth and sand that flows into one mass, and discharges the earth and sand that has flowed in when it falls more than a predetermined value, and the receiving portion When the amount of earth and sand discharged from one of the falling masses flows into one mass of the overturning mass exceeds a predetermined amount and the overturning mass falls down, the other mass can enter the earth and sand discharged from the receiving portion. A stopper that stops the fall of the overturning mass so as to be positioned, and a signal output unit that outputs a signal indicating the overturn when the overturning mass falls down, and the bottom surfaces of each of the pair of masses, A partition member that partitions a pair of masses Angle against along with formed to be an obtuse angle, the angle at which each of the bottom surface of the side where sediment flows forms together to form to be larger than 180 degrees.

As described above, since a falling mass having a pair of masses is provided, and the falling mass receives the earth and sand and outputs a signal indicating the falling, it is possible to easily measure sediment such as scavenging sand. it can. Moreover, since this earth and sand measuring apparatus can be easily created with a box, a receiving part, a falling mass, a stopper, and a signal output part, the manufacturing cost can be reduced and the apparatus can be miniaturized. In addition, the bottom surface of each of the pair of masses is formed so that the angle with respect to the partition member that partitions the pair of masses is an obtuse angle, and the angle formed by the bottom surfaces on the side into which the earth and sand flows is greater than 180 degrees. By forming in this way, it becomes easy to discharge the sediment accumulated in the mass.

  Note that the same weight may be provided for each of the pair of masses.

  Usually, when water pressure or the like is applied to the falling mass, it becomes difficult to fall, but by providing a weight in this way, it is easy to fall by the weight of the earth and sand, and the earth and sand can be measured smoothly.

  Furthermore, you may provide the guide member which guides earth and sand to the opening part of a box in the opening part vicinity of a box.

  By providing the guide member in this way, the earth and sand can be smoothly guided to the opening of the box, and the earth and sand can be measured smoothly with the falling mass in the box.

  As described above, according to the earth and sand measuring apparatus of the present invention, an excellent effect that earth and sand can be measured easily at low cost is obtained.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of the earth and sand measuring apparatus according to the present embodiment. This earth and sand measuring device 10 is an in-bed trap type measuring device that measures the amount of advancing sand that is embedded and fixed in the river bed and moves along the river bed.

  As shown in FIG. 1 (A), the sediment measuring apparatus 10 according to the present embodiment includes a sediment box 12 having a sediment box body 12a having an upper surface opened and an upper lid 12b covering the top surface of the sediment box body 12a. I have.

  The upper lid 12b is made of, for example, vinyl chloride or the like, and has an intake port 14 of a predetermined size for taking in the sweeping sand at the center. The intake 14 is provided with a mesh net 18 having a predetermined size so that dusts other than earth and sand do not flow into the sandbox 12. Moreover, the guide member 16 arrange | positioned along the flow of the river is provided in the inlet 14 vicinity of the upper cover 12b. The guide member 16 guides the sweeping sand moving in the river bed to the intake port 14.

  As shown in FIG. 1B, the sediment box main body 12a houses the main frame 30 that supports the overturning mass 40 and the like, and also stores the sweeping sand that has flowed from the intake port 14 of the upper lid 12b. Since the earth and sand falling from the overturning mass 40 accumulates below the overturning mass 40, the total amount of scavenging sand that can be measured is defined by the volume of the sandbox 12 itself and the shape of the bottom of the sandbox 12. The If the size of the sandbox 12 is made too small, the period during which continuous observation can be performed is shortened. Conversely, if the size of the sandbox 12 is made too large, installation work becomes large. It is preferable that the size is such that it can be continuously observed for the period of time and is easy to install.

  The main frame 30 housed and fixed in the sandbox 12 includes a funnel 20 that receives and discharges the scavenging sand flowing from the top lid 12b of the sandbox 12, and a falling mass 40 that receives and discharges the earth and sand discharged from the funnel 20. And the data logger 50 which records the date and time when the fall mass 40 fell is supported.

  FIG. 2 is a view showing the main frame 30 that supports the funnel 20 and the overturning mass 40. The main frame 30 is provided with four L-shaped steel members 32 erected as support columns. The four L-shaped steel members 32 support a funnel support member 33 that supports the conical funnel 20 at a predetermined height.

  The upper part of the funnel 20 supported by the funnel support member 33 is widely opened so as to receive the earth and sand flowing in from the intake port 14 of the sandbox 12, and the lower part of the funnel 20 receives the earth and sand from the intake port 14. A small opening is provided to discharge the falling mass 40 so that it can be received.

  Further, the main frame 30 is provided with a pair of falling mass support members 34, and is erected and fixed in parallel to the four L-shaped steel members 32 described above. In the holding hole 35 provided in each of the pair of falling mass support members 34, the end portion of the shaft body 36 that pivotally supports the falling mass 40 is inserted and supported. One of the pair of falling mass support members 34 is provided with a reed switch 37 that reacts with a magnet 47 (see FIG. 3) provided on the falling mass 40. When the falling mass 40 falls and the magnet 47 of the falling mass 40 crosses the reed switch 37, an electric pulse is generated and output to the data logger 50.

  A stopper 38 is provided between the pair of falling mass support members 34. When the predetermined amount of earth and sand flows into one of the pair of masses constituting the fall mass 40 and the fall mass 40 falls, the stopper 38 is in a position suitable for the other mass to receive earth and sand. Is provided to stop. Even if the overturning mass 40 is overturned by a predetermined value or more even before it is stopped by the stopper 38, discharging of the sediment accumulated in one of the masses is started.

  FIG. 3 is a front view of the overturning mass 40. The overturning mass 40 is composed of two masses of a first mass 41 and a second mass 42 having the same capacity. The first mass 41 and the second mass 42 are partitioned by a partition plate 44 having a triangular prism shape, and are adjacent to the partition plate 44 so as to be line symmetric.

  Unlike the overturn mass generally used for rain gauges, the overturn mass 40 is formed so that the angle formed between the partition plate 44 and the bottom surfaces of the first mass 41 and the second mass 42 is an obtuse angle. Side faces of rhombus shapes are provided on the side surfaces of the first mass 41 and the second mass 42 according to this angle.

  Sediment is unlikely to be drained unlike rainwater. However, by forming each of the first mass 41 and the second mass so that the angle formed between the bottom surface of the first mass 41 and the partition plate 44 becomes an obtuse angle, the earth and sand accumulated in the mass can be easily discharged. . Therefore, when the falling mass 40 falls, the earth and sand accumulated in the mass can be completely discharged without remaining.

  A shaft hole 46 is provided in the lower part of the partition plate 44. The shaft body 36 supported by the overturning mass support member 34 is inserted into the shaft body hole 46. With the shaft body 36 inserted in the shaft body hole 46 of the overturning mass 40 in this way, the end portion thereof is inserted into the holding hole 35 of the overturning mass support member 34 (see FIG. 2), so that the main frame 30 The overturning mass 40 can be supported below the supported funnel 20 so as to be overturned.

  Further, weights 48 and 49 having the same weight are provided on the bottom surfaces of the first mass 41 and the second mass 42, respectively. Since the earth and sand measuring device 10 is embedded in the riverbed, the sediment box 12 is filled with river water. Therefore, the falling mass 40 is subjected to water pressure and is less likely to fall than the falling mass of a rain gauge installed on the ground. However, by providing the weights 48 and 49 having the same weight on the bottom surfaces of the first mass 41 and the second mass 42 in this way, it is possible to easily fall over even when subjected to water pressure. The weights of the weights 48 and 49 can be adjusted according to the installation environment of the earth and sand measuring device 10 and the shape and size of the falling mass 40.

  Furthermore, a magnet 47 is provided above the shaft body hole 46, which is a partition portion between the first mass 41 and the second mass 42. The position of the magnet 47 varies depending on the posture variation of the falling mass 40. When the overturning mass 40 falls around the shaft body 36 (shaft body hole 46), the magnet 47 crosses the reed switch 37 provided in the overturning mass support member 34, and thus generates an electromotive force (electric pulse). The electric pulse is output to the data logger 50, and the data logger 50 can record the date and time when the overturning mass 40 is overturned together with the number of overturns by the input of the electric pulse.

  As shown in FIG. 1, the main frame 30 is also provided with a data logger 50 that receives the electric pulse output from the reed switch 37 and records the time when the falling mass 40 falls. In FIG. 2, the data logger 50 is not shown. The reed switch 37 and the data logger 50 are not shown, but are fixed to the main frame 30 in a simple waterproof case made of vinyl.

  The earth and sand measuring apparatus 10 configured as described above is installed on the river bed as follows.

  First, four iron plates are driven so as to surround a place where the earth and sand measuring device 10 is to be installed. Then, the river bed portion surrounded by four steel plates is excavated. The earth and sand measuring apparatus 10 is buried in the excavated place with the upper lid 12b of the sandbox 12 removed.

  After the earth and sand measuring device 10 is buried, the upper lid 12b is fixed to the sand box main body 12a so that air does not enter the sand box 12 and further piles are driven to fix the earth and sand measuring device 10 to the river bed. .

  FIG. 4 is a diagram schematically showing a state in which the earth and sand measuring device 10 is embedded and fixed in the river bed. In FIG. 4, illustrations of the columns (L-shaped steel material 32), the data logger 50, and the like of the main frame 30 are omitted so that the operation of the falling mass 40 constituting the earth and sand measuring device 10 can be easily understood.

  Next, the operation of measuring the amount of the sweeping sand by the earth and sand measuring device 10 installed on the river bed as shown in FIG. 4 will be described.

  As shown in FIG. 4, earth and sand move on the river bed surface (river sand). The moved earth and sand are guided to the intake port 14 by the guide member 16 provided on the upper lid 12 b of the earth and sand measuring device 10, and flow into the sediment box 12 from the intake port 14 through the net 18. The earth and sand flowing into the sediment box 12 is received by the funnel 20 and discharged downward (the falling mass 40).

  In the falling mass 40, the earth and sand discharged from the funnel 20 falls on one of the first mass 41 and the second mass 42. When the amount of earth and sand discharged from the funnel 20 and flowing into one mass of the overturning mass 40 exceeds a predetermined amount, the overturning mass 40 falls until it hits the stopper 38 with the weight of the earth and sand, and the earth and sand collected in the mass Is discharged downward and this time the opposite mass moves upward, so that new earth and sand discharged from the funnel 20 flows into the mass. During the measurement, the cycle in which the pair of masses alternately receive the earth, falls, and discharges is repeated in this way. When the overturning mass 40 falls, a magnet 47 provided on the overturning mass 40 crosses the reed switch 37 and an electric pulse is generated. This electric pulse is output to the data logger 50, and the date / time when the overturning mass 40 falls is recorded in the memory of the data logger 50 together with the number of falls.

  FIG. 5 is a flowchart showing the flow of a recording operation performed by the data logger 50. Here, this operation is started when a predetermined start time arrives.

  In step 100, it is determined whether or not an electrical pulse has been received from the reed switch 37. If it is determined that the electrical pulse has not been received, the process proceeds to step 106 to determine whether or not the measurement has been completed. Here, the measurement ends when the power is turned off or when a predetermined end time is reached.

  If it is determined in step 106 that the measurement has not ended, the process returns to step 100. If it is determined in step 100 that an electrical pulse has been received from the reed switch 37, the process proceeds to step 102 to acquire the current date and time. The current date and time is obtained from an internal clock built in the data logger 50. In step 104, the acquired date and time are recorded in a memory provided in the data logger 50 together with the number of falls (cumulative value). Thereafter, the process proceeds to step 106, and it is determined whether or not the measurement is completed as described above. The data logger 50 repeats steps 100 to 106 until it is determined that the measurement has been completed.

  In addition, the amount of earth and sand (volume or mass) when the overturning mass 40 overturns has been verified in advance by experiments, and if the number of overturns of the overturning mass 40 is recorded by the data logger 50, the amount of scavenging sand in the river bed is measured. can do.

  As described above, the sediment box 12 provided with the intake port 14 in the upper lid 12b, the funnel 20 that receives and discharges the earth and sand flowing from the intake port 14, and a pair of masses flowed into one mass. A fall mass 40 that falls according to the amount of earth and sand, a stopper 38 for stopping the fall mass 40 at a suitable position when the fall mass 40 falls, and a lead that generates an electric pulse when the fall mass 40 falls. Since the earth and sand measuring device 10 is constituted by the switch 37, the measuring device can be reduced in size and manufactured at a low cost without increasing the size of the measuring device, and can be easily installed on the river bed. Further, as described above, it is possible to measure the amount of scavenging sand only by recording the falling time and the number of falling times of the falling mass 40, so that it is extremely simple compared to the case of measuring with a load meter, an acoustic measuring device or the like. It is possible to measure the amount of sand flow.

  The sandbox 12 is not limited to the rectangular box exemplified in the above embodiment, and for example, a cylindrical sandbox 13 is used as shown in FIG. You may attach to the box 13 so that a fall is possible. By making the sedimentation box into such a shape, it can be easily pushed into the riverbed, and the labor for excavating the riverbed can be saved.

  Further, as shown in FIG. 7, a sand discharge pipe 22 is connected to the lower part of the sediment box main body 12a of the sediment measuring apparatus 10, and a pump 24 for discharging the sediment accumulated in the sediment box 12 to the outside is disposed of. It may be arranged in the tube 22. In this way, by providing the sandbox 12 and the pump 24 in the sandbox 12, there is no need to interrupt the measurement in order to discharge the accumulated sediment, and the period during which sediment can be measured continuously can be lengthened. it can.

It is a schematic block diagram of the earth and sand measuring apparatus which concerns on this Embodiment of this invention. It is the figure which showed the main frame which supported the funnel and the falling mass. It is a front view of a falling mass. It is the figure which showed typically the state where the earth and sand measuring device was embedded and fixed to the riverbed. It is a flowchart which shows the flow of the recording operation performed with a data logger. It is the figure which showed the modification of the sandbox. It is the figure which showed the modification of the earth and sand measuring apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Sediment measuring apparatus 12, 13 Sediment box 12a Sediment box main body 12b Top cover 14 Inlet 16 Guide member 20 Funnel 30 Main frame 32 L-shaped steel material 33 Funnel support member 34 Falling mass support member 36 Shaft body 38 Stopper 40 Falling mass 41 First mass 42 Second mass 44 Partition plate 46 Shaft hole 47 Magnet 50 Data logger

Claims (5)

A box having an opening;
A receiving part housed in the box so as to receive and discharge earth and sand flowing in from the opening of the box;
A falling mass comprising a pair of masses, supported in the box so as to be able to fall according to the amount of earth and sand that has flowed into one mass, and discharging the earth and sand that has flowed in when falling over a predetermined value;
When the amount of earth and sand discharged from the receiving portion and flowing into one mass of the overturning mass exceeds a predetermined amount and the overturning mass falls, the other mass flows into the earth and sand discharged from the receiving portion. A stopper for stopping the fall of the fall mass to be located at a possible position;
A signal output unit that outputs a signal indicating a fall when the fall mass has fallen;
Including
The bottom surface of each of the pair of masses is formed so that an angle with respect to a partition member that partitions the pair of masses is an obtuse angle, and an angle formed by the respective bottom surfaces on the side into which earth and sand flows is greater than 180 degrees. An earth and sand measuring device formed to be .   The earth and sand measuring apparatus according to claim 1, wherein a weight having the same weight is provided on each of the pair of masses.   The earth and sand measuring apparatus of Claim 1 or Claim 2 which provided the pump and sand discharge pipe which discharge the earth and sand discharged | emitted from the said falling mass outside.   The earth and sand measuring apparatus of any one of Claim 1 thru | or 3 which provided the guide member which guides the earth and sand to the said opening part in the opening part vicinity of the said box.   The earth-and-sand measuring apparatus of any one of Claim 1 thru | or 4 which provided the side plate of the rhombus shape according to the said angle on each side surface of said pair of mass.

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