JP2017194344A - Flooding risk diagnosis apparatus, flooding risk diagnostic method, controller, and computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flooding risk diagnosis apparatus, a flooding risk diagnostic method, a controller, and a computer program which can diagnose the risk of flooding in real time and provide a user with easy-to-understand results of the diagnosis at the same time in the diagnosis of the risk of flooding in a diagnosis target area.SOLUTION: The flooding risk diagnosis apparatus according to an embodiment includes: a parameter generating unit; an analysis model constructing unit; an outflow analysis unit; and a flooding analysis unit. The parameter generating unit generates a parameter necessary for constructing an analysis model for diagnosing the risk of flooding in a diagnosis target area based on a flow rate calculation table. The analysis model constructing unit constructs an analysis model based on the flow rate calculation table and the parameter. The outflow analysis unit calculates the flow rate for each tube path in a small drain area based on the analysis model. The flooding analysis unit calculates the degree of fullness of each tube path as an indicator of the risk of flooding in the small drain areas based on the flow rate of each tube path in the small drain area.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to an inundation risk diagnosis apparatus, an inundation risk diagnosis method, a control apparatus, and a computer program.

  In recent years, there has been a lot of local heavy rain (hereinafter referred to as "local heavy rain"), and the media has said "guerrilla heavy rain" in the sense that this local heavy rain does not know when and where it occurs. This word is now widely recognized by the general public. As a typical damage caused by local heavy rain, inundation floods occur frequently. In the past, the government has taken measures to prevent flooding, mainly in anticipation of flooding due to flooding or breakage of large rivers, such as embankments, river channel excavation, revetment construction and dam construction. River inundation is called outside water inundation. Conventionally, countermeasures against outside water inundation have been focused on, but in the future, it will be important to take into account inland water inundation.

  In fact, when we look at flood damage (outside water inundation, inland water inundation) in terms of damage amount, the damage amount of inland flooding accounts for about half of the total damage amount in the country, exceeding 90% of the total damage amount in Tokyo Yes. In this way, inundation is a new issue in urban areas where the development of dykes is relatively advanced.

  However, there are many cases where there is a trade-off between inundation and inundation. For example, a drainage facility such as a rainwater drainage pump or a drainage pumping station is added to the sewage treatment plant. And, if rainwater is discharged into the river by these drainage facilities in order to suppress the flooding of the inland water, the water level of the river rises and the risk of flooding the outside water is increased. On the other hand, delaying the start-up of the pump delays the risk of inland flooding if the pump activation is delayed in order to suppress flooding of the outside water. Therefore, it is important to operate drainage facilities that consider both inundation and inundation.

  Also, in urban areas with low altitudes (for example, Osaka and other areas), a drainage pumping station is installed near the mouth of the river, and the river water is discharged with the sluice closed to prevent backflow from the sea to the river. Has been done. It is desirable that the operation of such a drainage pumping station is performed by comprehensively considering the water level at the estuary and the amount of drainage at the drainage pumping station located upstream of the river. In order to adjust the trade-off between such inundation and inundation, pump operation adjustment rules may be introduced in drainage facilities such as drainage pump stations.

  The pump operation adjustment rule restricts the amount of drainage discharged to the river by suppressing or stopping the operation of the drainage pump when the river water level exceeds a certain level, and operates when the risk of flooding the outside water is avoided. The rule of the pump operation that restarts is established. However, since the flooding of the outside water and the flooding of the inside water are essentially in a trade-off relationship, it is not possible to achieve a fundamental solution only by setting the pump operation adjustment rule. In order to fundamentally solve the inundation and inundation, it is essential to take measures in terms of hardware, such as increasing the embankment according to the amount of rainfall and providing a storage facility.

  On the other hand, in recent years, heavy rains of 70-100 mm / h or more, which greatly exceed the planned rainfall (50-60 mm / h) set based on the probability rainfall of 5-10 years, have been observed relatively frequently. It is becoming like this. It is often difficult in terms of time and resources to implement all of these diversified rainfall measures in hardware. Therefore, in parallel with hardware measures, support for self-help efforts to avoid inundation damage by providing information such as rainfall information and inundation risk information, and more efficient drainage facilities such as storage facilities and drainage pumps. It is also necessary to implement software measures such as these as soon as possible.

  The main purpose of this hard and soft measure is to achieve complete inundation avoidance for rainfall below the planned rainfall, and for rainfall exceeding the planned rainfall, for example, on the floor. To avoid or reduce damage caused by flooding, such as avoiding flooding. When taking soft measures in addition to hard measures, information for comprehensively assessing the inundation risk of the entire city is extremely important. For example, distributed runoff analysis is widely used as a method for assessing inundation risk in the entire city. Distributed runoff analysis uses hydrological models and hydraulic models (Saint-Bennan equation) using topographic information such as land use pattern and elevation in a certain area, and civil engineering information such as sewage pipe laying conditions. Etc.) as appropriate, and the flow of rainfall (hereinafter referred to as “runoff”) is tracked. Distributed runoff analysis is widely used for rainfall runoff analysis, and many commercial software are sold.

  However, these commercial softwares are often used to design facilities that are installed mainly to avoid or reduce damage caused by floods and inundation. It was n’t. Some have functions for operational control, but they are not always widely used for the following reasons. First, there is a problem with the real-time nature of the analysis when analyzing the entire urban area. For example, when a wide area is an analysis target, civil engineering information and topographical information to be set are enormous, and the analysis requires a high cost. Another is that the analysis requires highly accurate rainfall data. In recent years, the Ministry of Land, Infrastructure, Transport and Tourism has provided highly accurate rainfall data (hereinafter referred to as “radar rainfall data”) acquired by X-band MP radar (Xrain) installed at 35 locations nationwide. However, this radar rainfall data may not always be provided in a data format suitable for runoff analysis. Therefore, when using radar rainfall data provided by the Ministry of Land, Infrastructure, Transport and Tourism, processing such as conversion to a data format suitable for runoff analysis is required.

  In order to solve such problems, various outflow analysis techniques have been proposed. However, the conventionally proposed methods provide a method for adapting radar rainfall data to existing methods such as runoff analysis and flood analysis, or a method for reducing labor when using radar rainfall data. In addition, the methods proposed in the past are basically applicable to the flooding of outside water caused by rivers, and elements specific to inland flooding such as the structure of sewer pipes are not considered. .

  On the other hand, in drainage facilities such as sewage treatment plants and drainage pump stations, conventionally, rainwater inflow prediction for predicting the amount of rainwater flowing into the drainage facility has been performed mainly for the purpose of supporting operation of the equipment. Various methods for realizing rainwater inflow prediction have been proposed. However, the conventional method is generally a method in which the amount of rainwater flowing into the drainage facility is estimated in a data-driven manner based on past performance values. On the other hand, some methods have been proposed to analyze the flow rate and inundation risk of virtual sewer pipes set for each mesh using the rainfall data acquired for each diagnosis target area divided into meshes as input. ing. However, since such an analysis method does not assume an actual sewage pipe, the analysis result is often difficult for a user such as a sewer company or a sewer manager. As described above, the conventionally proposed analysis methods are not compatible with real-time inundation risk diagnosis and providing diagnosis results that are easy for the user to understand.

JP 2009-8651 A JP 2005-128838 A JP 2004-62440 A JP 2000-257140 A Japanese Patent No. 4682178 Japanese Patent No. 4399122 Japanese Patent No. 4185910 Japanese Patent No. 4082686

  The problem to be solved by the present invention is that the inundation risk diagnosis apparatus capable of achieving both in real-time inundation risk diagnosis and providing easy-to-understand diagnosis results for the inundation risk diagnosis in the diagnosis target area. An inundation risk diagnosis method, a control device, and a computer program are provided.

  The inundation risk diagnosis apparatus according to the embodiment includes a parameter generation unit, an analysis model construction unit, an outflow analysis unit, and an inundation analysis unit. The parameter generation unit generates parameters necessary for constructing an analysis model for diagnosing the inundation risk in the diagnosis target area based on various amounts indicated by the flow rate calculation table of the diagnosis target area. The analysis model construction unit constructs the analysis model based on the various quantities and the parameters. The runoff analysis unit, based on the analysis model constructed by the analysis model construction unit and the rainfall data acquired at a predetermined cycle for each small drainage district of the diagnosis target area, the pipeline in each small drainage district Each flow rate is calculated. The inundation analysis unit calculates a full pipe rate for each of the pipelines, which is an index of the inundation risk of the small drainage districts, based on the flow rate of each pipeline in each of the small drainage districts calculated by the outflow analysis unit.

The block diagram which shows the outline of a function structure of the inundation risk diagnostic apparatus 1 of 1st Embodiment. The figure which shows the specific example of a flow volume calculation table. The figure which shows the specific example of the pipe line which connects a small drainage area and each small drainage area. The figure which shows one specific example of the aspect by which an analysis result is displayed. The figure which shows one specific example of the aspect by which an analysis result is displayed. The figure which shows the specific example of the directed graph which shows the inflow relationship of each pipe line. The figure which shows the specific example of the matrix which shows the connection relation of each pipe line. The figure which shows the specific example of a conversion table. The figure which shows the specific example of the drawing data divided | segmented into the mesh. The block diagram which shows the outline of a function structure of the inundation risk diagnostic apparatus 1a of 2nd Embodiment.

  Hereinafter, an inundation risk diagnosis apparatus, an inundation risk diagnosis method, a control apparatus, and a computer program according to embodiments will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a block diagram illustrating an outline of a functional configuration of an inundation risk diagnosis apparatus 1 according to the first embodiment. The inundation risk diagnosis apparatus 1 includes a CPU (Central Processing Unit), a memory, an auxiliary storage device, and the like connected by a bus, and executes a diagnosis program. The inundation risk diagnosis apparatus 1 is configured by executing a diagnostic program, a flow rate calculation table storage unit 101, an analysis model parameter generation unit 102, an analysis model construction unit 103, a rainfall data acquisition unit 104, a preprocessing unit 105, a runoff analysis unit 106, and an inundation analysis. It functions as a device including the unit 107 and the analysis result display unit 108. Note that all or part of each function of the inundation risk diagnosis apparatus 1 may be realized by using hardware such as an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA). Good. The diagnostic program may be recorded on a computer-readable recording medium. The computer-readable recording medium is, for example, a portable medium such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM, or a storage device such as a hard disk built in the computer system. The diagnostic program may be transmitted via a telecommunication line.

  The flow rate calculation table storage unit 101 is configured using a storage device such as a magnetic hard disk device or a semiconductor storage device. The flow rate calculation table storage unit 101 stores a flow rate calculation table in advance. The flow rate calculation table is information used for sewerage planning, and is information that is usually held by sewerage companies such as local governments and sewerage managers.

  FIG. 2 is a diagram showing a specific example of the flow rate calculation table. The flow rate calculation table 100 in FIG. 2 has a number of flow rate calculation records corresponding to the number of small drainage areas. The small drainage area referred to here means each area where an area subject to diagnosis of inundation risk (hereinafter referred to as “diagnosis target area”) is divided based on a sewer plan. The flow rate calculation record has items of line number, inflow line number, area, outflow coefficient, flow time, flow velocity, extension, and cross section. The line number is the identification number of the small drainage area. The line number may be an identification number of a pipe line connecting the small drainage areas. The inflow line number is the line number of the small drainage area connected to the upstream side of the small drainage area indicated by the line number. The area is the drainage area of the small drainage area (or pipe line) indicated by the line number. The drainage area is the area where rainwater and sewage are collected in a small drainage area.

  The runoff coefficient represents the runoff coefficient of the small drainage area indicated by the line number. The runoff coefficient is the ratio of rainwater that flows down the ground surface to the amount of rainfall. The flow time represents the flow time of the small drainage area indicated by the line number. The flow time is the time required for rainwater to flow from the remotest point in the small drainage area to the drainage channel and to the point where the inflowing rainwater flows through the drainage channel. Expressed as the sum of the flow time and sum. The flow velocity represents a planned value (hereinafter referred to as “planned flow velocity”) of the speed of water flowing through a pipe connecting the small drainage area indicated by the line number and the upstream small drainage area indicated by the inflow line number. The extension represents the length of the pipe line connecting the small drainage area indicated by the line number and the upstream small drainage area indicated by the inflow line number. The cross section represents the cross-sectional area of the pipe line connecting the small drainage area indicated by the line number and the upstream small drainage area indicated by the inflow line number.

  In the flow rate calculation table, when the flow velocity is undefined, the gradient and roughness of the pipeline may be used instead of the flow velocity. In this case, the flow rate can be defined by the gradient and roughness of the pipe line by using the Manning equation described later.

  FIG. 3 is a diagram showing a specific example of a small drainage area and a pipe line connecting each small drainage area. The diagnosis target area 20 illustrated in FIG. 3 is divided into eight small drainage areas A1 to A8. Junction points 21-1 to 21-8 shown in each small drainage zone are junctions of pipe lines connecting adjacent small drainage zones. In the example of FIG. 3, each small drainage area has one junction 21. In other words, the small drainage area can be said to be an area in which the diagnosis target area is divided at each junction. A line connecting each junction 21 represents a pipe line connecting each small drainage section. In the example of FIG. 3, seven pipelines 22-1 to 22-7 are shown for the eight small drainage areas and the junction 21.

  Returning to the description of FIG. The analysis model parameter generation unit 102 extracts various amounts necessary for construction of an analysis model (specifically, an outflow analysis model and an inundation analysis model) used for diagnosis of inundation risk from the flow calculation table, and extracts the extracted amounts. Generate as a parameter table for each small drainage area. The analysis model parameter generation unit 102 outputs the generated parameter table to the analysis model construction unit 103 and the inundation analysis unit 106.

  Based on the parameter table for each small drainage area generated by the analysis model parameter generation unit 102, the analysis model construction unit 103 is a group of equations representing the balance of water amount, (continuous equation) water motion (movement equation), and the like. Is constructed as the above analysis model. The analysis model construction unit 103 outputs the constructed analysis model to the outflow analysis unit 106.

  The rainfall data acquisition unit 104 acquires rainfall data indicating time-series precipitation in each small drainage area. Rainfall data may be acquired in any manner as long as it is information indicating precipitation in time series in each small drainage area. The rainfall data acquisition unit 104 outputs the acquired rainfall data to the outflow analysis unit 106. The rainfall data acquired by the rainfall data acquisition unit 104 is acquired as data indicating the rainfall for each area (hereinafter referred to as “mesh”) obtained by dividing the diagnosis target area into a mesh pattern.

  The preprocessing unit 105 performs preprocessing on the rainfall data acquired by the rainfall data acquisition unit 104 and outputs it to the outflow analysis unit 106.

  The runoff analysis unit 106 performs runoff analysis based on the rainfall data acquired by the rainfall data acquisition unit 104 and the analysis model (specifically, the runoff analysis model) constructed by the analysis model construction unit 103. The flow rate, water level, etc. of the pipes connecting each small drainage area are calculated in real time (specifically, an update cycle of several seconds to several minutes). The outflow analysis unit 106 outputs the result of the outflow analysis to the inundation analysis unit 106 and the analysis result display unit 108.

  The inundation analysis unit 107 includes a result of the outflow analysis by the outflow analysis unit 106, an analysis model (specifically, an inundation analysis model) constructed by the analysis model construction unit 103, and a small model generated by the analysis model parameter generation unit 102. Based on the parameter table for each drainage area, inundation analysis is performed to calculate the full pipe ratio that is the index value of the inundation risk. The full pipe rate is a ratio of the flow rate to the capacity of the pipe line (hereinafter referred to as “full pipe capacity”). The inundation analysis unit 107 calculates the full capacity of each pipeline based on the cross section and extension included in the parameter table. The inundation analysis unit 107 outputs the result of the inundation analysis to the analysis result display unit 108.

  The analysis result display unit 108 includes a display device such as a CRT (Cathode Ray Tube) display, a liquid crystal display, and an organic EL (Electro-Luminescence) display, and results of runoff analysis and inundation analysis (hereinafter referred to as “analysis results”). Display information to be displayed on the screen. The analysis result display unit 108 outputs the generated display information to the display device, and displays the analysis result. The analysis result display unit 108 may be configured as a functional unit that provides display information to an external device including the display device. Specifically, the analysis result display unit 108 generates display information such that the analysis result is displayed in such a manner that the inundation risk can be visually grasped. In this case, the analysis result display unit 108 determines the inundation risk by comparing the analysis result with a predetermined threshold value set in advance, and the visual effect is applied to the pipeline or small drainage area determined to be high in risk. The display information that gives is generated. The visual effect imparted to the display information may be any effect that can visually convey the inundation risk, such as color, text, thickness, and line type.

  FIG. 4 is a diagram illustrating a specific example of an aspect in which an analysis result is displayed. FIG. 4 shows an example in which the risk of flooding is high in the pipelines 22-1, 22-2, 22-3, 22-5, and 22-6 among the seven pipelines 22-1 to 22-7. It is. FIG. 4 is an example in which the presence or absence of a flood risk is represented by the thickness of a line indicating a pipeline, and the height of the flood risk is represented by a line type. In addition, the selection display 30 of FIG. 4 is a display which shows the transition of the fullness rate of the pipe line selected on the screen. In this manner, the analysis result display screen has information (hereinafter referred to as “related information”) related to objects on the display screen (specifically, pipelines, junctions, small drainage areas, etc.) according to the user's selection. May be configured to be displayed. For example, in this case, the analysis result display unit 108 accumulates the analysis results of the outflow analysis unit 106 and the inundation analysis unit 107 for a predetermined period, and extracts the related information of the selected object from the accumulated analysis results. Then, the analysis result display unit 108 generates display information for displaying the acquired related information as the selection display 30, and outputs the display information to the display device.

  FIG. 5 is a diagram illustrating a specific example of an aspect in which an analysis result is displayed. FIG. 5 is an example in which the inundation risk is expressed by shading shading of a small drainage area in addition to the display mode of FIG. In this case, if inundation risk is recognized in two pipes as in the small drainage area A3, the shaded concentration of the small drainage area A3 may be set to a concentration corresponding to the average of the inundation risk, and the higher one The concentration may be in accordance with the risk of flooding. Further, the inundation risk at each point in the small drainage area A3 may be calculated according to the distance from each pipeline, and the small drainage area A3 may be displayed at a concentration according to the inundation risk at each point.

  Details of the outflow analysis and the inundation analysis will be described below. First, the construction of an analysis model used for runoff analysis and inundation analysis will be described.

[Analysis model construction]
First, the analysis model construction unit 103 generates a directed graph representing the relationship of water flowing into each pipeline (hereinafter referred to as “inflow relationship”) based on the parameter table.

FIG. 6 is a diagram showing a specific example of a directed graph showing the inflow relationship of each pipeline. FIG. 6 is an example of a directed graph showing the inflow relationship in the diagnosis target area of FIGS. Nodes 41-1 to 41-8 represent the junction 21 of each pipeline. That is, the nodes 41-1 to 41-8 correspond to the small drainage areas A1 to A8. Each solid arrow represents a pipeline connecting each node, and the direction of the arrow representing each pipeline represents the direction in which water flows down. Each broken-line arrow represents rainwater flowing into each node 41 (that is, a small drainage area). Q _{A1 to} Q _A8 appended to each broken-line arrow represent the inflow amount of rainwater flowing into each small drainage area. The amount of inflow into each small drainage area is obtained by converting the amount of rainfall into each small drainage area based on the drainage area and runoff coefficient. The directed graph in FIG. 6 means that rainwater that has flowed into each small drainage area finally flows into the small drainage area A1. In addition, it can replace with said directed graph and can represent the connection relationship of each pipe line in a matrix form.

  FIG. 7 is a diagram illustrating a specific example of a matrix indicating the connection relation of each pipeline. FIG. 7 is an example in which the connection relationships of the pipes shown in the directed graph of FIG. 6 are represented in a matrix format. In FIG. 7, a row represents a downstream node, and a column represents an upstream node. For example, the value “1” in 2 rows and 1 column indicates that the node identified by “1” is connected to the upstream side of the node identified by “2”. By expressing in such a matrix format, the connection relationship of each pipeline can be expressed in a more quantitative and easy-to-understand format.

  Subsequently, the analysis model construction unit 103 constructs an outflow analysis model by applying the connection relation of the pipes expressed as described above to the basic expression of the analysis model. The basic formula of the analysis model used here is a formula that expresses the balance of water volume (continuous formula), a formula that expresses the inflow of rainfall, a formula that expresses the movement of the inflowing rainwater (the formula of motion), and the like. The analysis model construction unit 103 constructs an outflow analysis model by applying and combining the connection relations of the pipes to these basic expressions. The following formula (1) is given as a typical example of the outflow analysis model constructed in this way.

In formula (1), Q _A ^* represents the inflow of rainwater into each small drainage area. In addition, “*” of Q _A ^* is a symbol that means all the values of Q _A for each small drainage area. For example, when there are 1 to 100 small drainage areas, “*” means to take a value of 1 to 100 corresponding to each small drainage area. That is, Formula (1) represents Formula (1) defined for every small drainage area with one formula. In the following, “*” in each formula is used in the same meaning as in formula (1). Moreover, in the following description, each symbol used in the mathematical expression may be described without “*”.

R _A ^* represents the intensity of rainfall for each small drainage area (hereinafter referred to as “rain intensity”). For the rainfall intensity, radar rainfall data (data generated based on the radar rainfall data) may be used, or rainfall data acquired by a ground rain gauge installed in each small drainage area may be used. A ^* represents the drainage area of each small drainage area. F _A ^* represents the (average) runoff coefficient of each small drainage area. T _in ^* represents the (average) inflow time of each drainage area. The formula for calculating T _in ^* is expressed by the following equation (2).

  The continuous equation is represented by the following equation (3).

In Formula (3), S ^* represents the amount of rainwater stored in each small drainage area. The first term on the right side is the amount of inflow into each small drainage area obtained by equation (1). J in the second term on the right side represents the identification number of the adjacent small drain-ku, Q _j denotes an inflow of rainwater flowing from small drain ku identified by j. That is, the second term on the right side represents the total inflow amount of rainwater flowing from the adjacent small drainage area. Q ^{* in} the third term on the right side represents the amount of rainwater that flows into the adjacent small drainage area.

  The equation of motion is expressed by the following equation (4).

  Equation (4) is a simplified expression of a general motion equation, and K is the reciprocal of the flow time. In addition, when using Formula (4) as a motion formula, it is a premise that the flow velocity of each pipeline is obtained. In general, the flow velocity of each pipe line can be obtained from a flow rate calculation table. However, if this flow velocity cannot be obtained, it is also possible to calculate the flow velocity using a Manning equation. The Manning formula is expressed by the following formula (5), and it assumes a full or semi-full pipe state from information indicating the physical configuration of the pipe line such as shape and extension (hereinafter referred to as “pipe line information”). It is possible to calculate the flow velocity of the pipeline.

In Expression (5), R represents the diameter depth of rainwater flowing down the pipeline assuming a full or half-filled state. I represents the slope of the pipeline and D represents the diameter of the pipeline. In this case, first, the flow velocity is obtained by the Manning equation of equation (5), and the parameter K may be calculated from the obtained flow velocity. In addition, when n, R, and I in Formula (5) are acquired as parameters for each small drainage area, n, R, and I in Formula (5) are represented as n ^* , R ^* , and I ^* , respectively. May be.

On the other hand, when it is desired to perform an analysis in consideration of the change in the flow velocity according to the change in the diameter depth, the Manning equation of Equation (5) may be incorporated into the equation of motion of Equation (4). In this case, the outflow amount Q ^* can be obtained by the following equations (6) to (9). Note that, similarly to the formula (5), A _d , θ, D, n, R, and I in the following formulas (6) to (9) are A _d ^* , θ ^* , D ^* , n ^* , R ^* , It may be expressed as I ^* .

In the formula (6), A _d represents the cross-sectional area of flow through the conduit (Nagareseki), n represents roughness. H _S ^* represents the water level in the pipeline and L _S represents the extension of the pipeline. Since equation (6) to (9) representing the flow rate ^{Q *} as a function of the water level ^{H *,} the formula (6) is used to Formula (9), the water level _H ^{s *} and storage amount ^{S *} and of It is necessary to calculate the relationship. In fact, the water level H _s ^* Because can be converted by using the structure data of the sewage pipe from the storage amount S ^* (such as conduit diameter and extension) can be expressed as a function of the storage amount S ^*. If such a function is obtained, Expression (9) can be expressed as a function of S ^* , and Expression (6) can also be expressed as a function of S ^* . As a result, Expression (3) can be analyzed using Expression (6) to Expression (9). Specifically, Formula (9) can be expressed as a function of S ^* by performing the following approximation.

In general, the function representing the relationship between the water level H _s ^* and the storage amount S ^* (here, if F is assumed, H _s ^* = F (S ^* )) depends on the physical shape of the sewer pipe. Therefore, when the sewer pipe is a circular pipe, the function F is a somewhat complicated expression. On the other hand, when the sewer pipe is a rectangular pipe, assuming that the bottom area of the rectangular pipe is A, the height of the rectangular pipe is D, and the actual water level is H _s , the full pipe capacity S _max is S _max = A × D. the amount S becomes _S = a × _{H s.} In this case, the full pipe ratio S / S _max is expressed as S / S _max = (A × H _s ) / (A × D) = H _s / D. Since Equation (9) is an equation assuming a circular pipe, H _s ^* / D in the equation does not coincide with the full pipe ratio, but when performing a simple calculation, approximately H _s ^* / D can be regarded as the fullness rate. If approximated in this way, H _s ^* / D = S ^* / S _max can be obtained, and Equation (9) can be used as a function of the storage amount S ^* . Therefore, when performing a simple calculation, the water level H _s ^* in Expression (9) is expressed by the full pipe ratio obtained by dividing the storage amount S ^* by the full pipe capacity S _max , thereby obtaining the expression (6 ) To Equation (9) can be analyzed in the differential equation obtained by substituting Equation (9) into Equation (3). In this way, when the equations (6) to (9) are used as equations of motion instead of the equation (4), phenomena that change with the water level, such as the flow velocity and the flow time, can be approximately analyzed, The accuracy of analysis can be improved.

Furthermore, if the pipe slope I is simulated by a hydrodynamic slope, it will be possible to analyze how the flow time will increase as the downstream water level rises. It becomes possible. For example, the hydraulic gradient I _d can be calculated by the following equation (6).

In the equation (10), S _update represents the fullness of the upstream pipeline, and _Sdnrate represents the _fullness of the downstream pipeline. In addition, when there are a plurality of upstream pipelines, an average value of the plurality of pipelines may be used for S _uprate and S _dnrate . By using such a hydraulic gradient, it is possible to analyze the phenomenon in which the flow rate becomes slow when the downstream fullness rate is larger than the upstream fullness rate (that is, when the hydraulic gradient is small). it can.

  Next, the outflow analysis based on the analysis model generated by the above method will be described.

[Outflow analysis]
First, the preprocessing unit 105 performs preprocessing of information necessary for outflow analysis. Specifically, the preprocessing unit 105 performs the following two preprocessing.

(1. Correlation between rainfall data and small drainage areas)
In general, the rainfall data is acquired for each area in which the diagnosis target area is divided into meshes. Therefore, in order to input rain data into the analysis model, it is necessary to convert rain data acquired for each mesh (hereinafter referred to as “mesh rain data”) into rain data for each small drainage area. Therefore, the preprocessing unit 105 generates a conversion table for converting the mesh rainfall data into the rainfall data of each small drainage area using drawing data that can identify the boundaries of the small drainage areas in the diagnosis target area. In addition, the above drawing data can be generated based on the division plan that is usually owned by a sewer company such as a local government or a sewer manager, and is set in the inundation risk diagnosis apparatus 1 in advance. And

  FIG. 8 is a diagram illustrating a specific example of the conversion table. The conversion table in the example of FIG. 8 has a conversion record for each small drainage area. The conversion record has each item of a small drainage area number, a small drainage area, and an area ratio. The small drainage area number is an identification number of each small drainage area. The small drainage area is the area of the small drainage area indicated by the small drainage area number. The area ratio has a value for each identification information of each mesh, and represents the ratio of the area of each mesh to the small drainage area. FIG. 8 is an example in which the identification information of each mesh is expressed as x and y coordinates. For example, in the example of FIG. 8, the mesh identified by (x, y) = (2, 1) occupies 20 of the area “100” of the small drainage area identified by the small drainage area number “1”. It represents that. Such a conversion table can be generated by dividing the drawing data of the diagnosis target area into each mesh which is a unit for obtaining mesh rainfall data.

(2. Conversion of rainfall data)
FIG. 9 is a diagram illustrating a specific example of drawing data divided into meshes. The size of each mesh is known. Therefore, the pre-processing unit 105 can calculate the area of each small drainage area by linearly approximating the boundary line of each small drainage area, and can calculate the ratio of the area of each mesh in each small drainage area. it can. Based on the conversion table generated in this way, the preprocessing unit 105 converts the mesh rainfall data into the rainfall data of each small drainage area and outputs the rainfall data to the outflow analysis unit 106.

  Specifically, when converting the mesh rainfall data for a certain small drainage area A, the preprocessing unit 105 first refers to the conversion table and selects a conversion record having a small drainage area number corresponding to the small drainage area A. . The preprocessing unit 105 refers to the value of the area ratio of the selected conversion record, and identifies the mesh corresponding to the small drainage area A. Specifically, the preprocessing unit 105 selects a mesh whose area ratio value is not zero from the selected conversion record. The pre-processing unit 105 converts the mesh rainfall data into the rainfall data of the small drainage area A by calculating the weighted sum of the mesh rainfall data with the area ratio of each selected mesh as a weight.

For example, when the meshes corresponding to the small drainage area A are M ₁ , M ₂ and M ₃ and the respective area ratios are 0.2, 0.7 and 0.1, the rainfall data R of the small drainage area A _a can be calculated by the following equation (11).

In the formula (11), R ₁ , R ₂ and R ₃ represent mesh rainfall data of M ₁ , M ₂ and M ₃ , respectively. Note that the conversion record of small drain locations A, by setting in advance the zero value of the area ratio of the mesh which does not correspond to small drain ku A (weight), precipitation data R _a small drainage District A has the following formula It can be calculated by (12).

In Expression (12), k represents the identification number of the mesh in the diagnosis target area, and N represents the maximum value. W _k represents the area ratio of the mesh identified by k, and R _k represents the mesh rainfall data of the mesh identified by k. Thus, for each small drainage area, by setting the area ratio of the mesh not applicable to zero in advance, the expression (12) is always generated without generating the expression (11) for each small drainage area to be converted. Only with rain data can be converted.

  The preprocessing unit 105 outputs the converted rainfall data generated by the above preprocessing to the outflow analysis unit 106. In practice, it is assumed that the size of each small drainage area is often smaller than the size of one mesh, but here the size of each small drainage area is larger than one mesh for simplicity. expressing. The mesh rainfall data is acquired as a two-dimensional array of meshes defined in the x and y coordinate format. For example, mesh rainfall data is acquired as time-series data in units of 1 minute.

  The runoff analysis unit 106 performs runoff analysis based on the converted rainfall data generated by the preprocessing unit and the analysis model constructed by the analysis model construction unit 103. Specifically, the runoff analysis unit 106 solves the continuous formula and the formula of motion represented by the formulas (1) to (10) using the connection relation of the small drainage areas, the inflow amount, the outflow amount, and the like as boundary conditions. Thus, the flow rate and the water level of the pipe line connecting each small drainage area are calculated. The outflow analysis unit 106 outputs information such as the flow rate and water level of each pipeline obtained by the outflow analysis to the inundation analysis unit 106 and the analysis result display unit 108 as analysis results. If necessary, the outflow analysis unit 106 may convert the flow rate information into the water level information using the pipeline information of each pipeline.

  It should be noted that the inflow delay required for the rainwater due to rain to flow into the small drainage area is not represented by a pure time delay as in Expression (1), but is expressed by a primary delay filter as in the following Expressions (13) to (14). It is also possible.

  In Expression (14), s represents a Laplace operator. The introduction of such a first-order lag filter not only delays the time until the rain flows in, but also suppresses the peak of the rain waveform, so that it is possible to analyze a phenomenon closer to a more realistic outflow.

  Next, the inundation analysis based on the outflow analysis result obtained by the above method will be described.

[Inundation analysis]
The inundation analysis unit 107 includes a result of the outflow analysis by the outflow analysis unit 106, an analysis model (specifically, an inundation analysis model) constructed by the analysis model construction unit 103, and a small model generated by the analysis model parameter generation unit 102. Based on the parameter table for each drainage area, inundation analysis is performed to calculate the full pipe ratio that is the index value of the inundation risk. Specifically, the inundation analysis unit 107 calculates the full pipe rate S _flood by dividing the storage amount S ^* of each pipe line indicated by the result of the outflow analysis by the capacity (full pipe capacity) S _max of the pipe line. . In other words, the full pipe ratio S _flood is defined by S _flood = S ^* / S _max ^* . The inundation analysis unit 107 outputs the calculated full rate S _flood of each pipeline to the analysis result display unit 108 as a result of the inundation analysis.

  Next, display of analysis results will be described.

[Display analysis results]
The analysis result display unit 108 determines the inundation risk of each small drainage area based on the result of the inundation analysis. Specifically, it is determined that the analysis result display unit 108 and the pipe line with the full pipe ratio S _flood <1 are in an overflow state and the inundation risk is high. Meanwhile, flooding analysis unit 107, the conduit is full bobbin ratio _{S flood} <1 no overflow condition, determines flooding risk is low. The analysis result display unit 108 displays the inundation risk of each small drainage area thus determined as an inundation hazard map as shown in FIGS. 4 and 5.

For example, the analysis result display unit 108 displays the pipelines with S _flood > 1 in red and displays the pipelines with 0.8 <S _flood <1 in yellow. May be displayed. In this way, by displaying the inundation risk of each small drainage area in the form of a visually identifiable inundation hazard map, sewer operators and sewer managers can more easily determine the inundation risk in the diagnosis target area. It becomes possible.

  The inundation risk diagnosis apparatus 1 according to the first embodiment configured as described above can perform the outflow analysis and the inundation analysis based on the information of the sewer plan (flow rate calculation table) normally owned by the sewer company. . By providing such a configuration, in the diagnosis of the inundation risk in the diagnosis target area, it is possible to achieve both the diagnosis of the inundation risk in real time and the provision of a diagnosis result that is easy for the user to understand.

  According to the inundation risk diagnosis apparatus 1 of the first embodiment configured as described above, the following effects can be expected. The sewer plan is used for the physical design of sewer pipes. Therefore, by using such sewer plan information for diagnosis of inundation risk, engineers who take measures against inundation in hardware such as augmented trunk lines and storage facility construction, and software such as pump operation and gate operation of storage facilities, etc. It is possible to reduce the communication gap between engineers who take measures against flooding.

  Moreover, the inundation risk diagnosis apparatus 1 performs runoff analysis and inundation analysis in real time according to the acquisition of rainfall data. Furthermore, the inundation risk diagnosis apparatus 1 displays the analysis results of the outflow analysis and the inundation analysis performed in real time as an inundation hazard map that allows easy visual identification. By providing such a function, it is possible to improve the diagnosis accuracy of the inundation risk and reduce inundation damage.

(Second Embodiment)
FIG. 10 is a block diagram illustrating an outline of a functional configuration of the inundation risk diagnosis apparatus 1a according to the second embodiment. The inundation risk diagnosis apparatus 1a of the second embodiment differs from the inundation risk diagnosis apparatus 1 of the first embodiment in that it further includes a measurement data acquisition unit 109 and an analysis model parameter adjustment unit 110. The measurement data acquisition unit 109 acquires measurement information such as the water level and flow rate of the pipeline from measurement devices such as a water level sensor and a flow rate sensor installed in each pipeline.

  The analysis model parameter adjustment unit 110 adjusts some parameters included in the parameter table based on the measurement information acquired by the measurement data acquisition unit 109. The analysis model parameter adjustment unit 110 inputs the adjusted parameter to the outflow analysis unit 106 by updating the parameter table with the adjusted parameter.

  The runoff analysis unit 106 calculates the flow rate or water level information of the pipes connecting the respective small drainage areas. In general, this is the actual observed flow rate or observed water level measured by the measurement data acquisition unit 109. In many cases, they do not match and have an analysis error. Therefore, the analysis model parameter adjustment unit 110 calculates the optimum values (minimum values) of some parameters included in the parameter table using the sum of the square error and absolute value error of the analysis error in a predetermined period as an evaluation index.

  Specifically, among the parameters shown in FIGS. 4 and 5, parameters that are considered to have relatively high uncertainty are roughness, runoff coefficient, and flow time. The analysis model parameter adjustment unit 110 selects some or all of these parameters as parameters to be adjusted. The analysis model parameter adjustment unit 110 adjusts the selected parameter using a method such as data assimilation so that the analysis error is reduced.

  The data assimilation method is a general term for a methodology for adjusting initial values, boundary values, or parameters of state variables of an analysis model so that an error between a measurement value and an analysis value becomes small. As a data assimilation method, a four-dimensional variation method that is a batch processing method, a particle filter (particle filter) that is a sequential processing method, an ensemble Kalman filter, and the like are widely known. The inundation risk diagnosis apparatus 1a of the present embodiment is intended to realize a diagnosis of inundation risk in real time (several seconds to several minutes). Therefore, the data assimilation method includes a sequential particle filter and an ensemble Kalman filter. Is preferably used.

  In addition, the optimization of the analysis error is not limited to the above data assimilation method, and other optimization methods may be used. For example, heuristic optimization methods called metaheuristics such as genetic algorithms (GA) and particle swarm optimization (PSO) may be used as other optimization methods. .

  In this embodiment, in addition to radar rainfall data, it is assumed that sensors capable of measuring water level or flow rate in real time are installed at a plurality of points in one or more locations in the sewer pipe. The measurement data acquisition unit 109 acquires measurement information at the same cycle as the radar rain data acquisition cycle or at a cycle shorter than that. If the measurement information acquisition cycle is longer than the radar rain data acquisition cycle, the radar rain data acquisition cycle is synchronized with the measurement information acquisition cycle.

  The inundation risk diagnosis apparatus 1a of the second embodiment configured as described above adjusts analysis model parameter adjustment for adjusting parameters of an analysis model necessary for inundation risk diagnosis based on analysis results and actual measurement data. The unit 110 is provided. By providing such a configuration, it is possible to improve the accuracy of outflow analysis and inundation analysis.

  Hereinafter, modified examples of the inundation risk diagnosis apparatus of the embodiment will be described.

  The analysis results of the outflow analysis unit 106 and the inundation analysis unit 107 may be used not only for displaying the inundation hazard map by the analysis result display unit 108 but also for controlling the operation of the drainage facility. For example, if such an analysis result is used for operation control of a drainage pump station, the drainage pump can be started at an appropriate timing according to the inundation situation. In general, the drainage pump station is located at the root node (“1” in FIG. 6) in the above directed graph, and the inflow amount can be estimated by the outflow analysis. And if the inflow to the drainage pump station can be estimated, the number of drainage pumps necessary to drain the inflow can be determined, and the required number of drainage pumps can be activated at an appropriate timing. . Moreover, based on the inflow obtained by the outflow analysis, it is possible to support the operation of changing the set values of the pump start water level and the stop water level. The support for the change operation may be realized by automatically controlling the setting value, or may be realized by notifying the operator of information such as the setting timing and the setting value.

  For example, if such an analysis result is used for operation control of a rainwater storage facility, the opening and closing of the storage gate can be controlled at an appropriate timing according to the inundation situation. For example, as a result of inundation analysis, when a pipeline with a full pipe ratio exceeding a predetermined threshold occurs, control can be performed to open the gate of a storage facility to which the pipeline is connected directly or indirectly. . Such gate control may be performed in combination with other phenomena and trends. For example, when a pipeline with a full pipe ratio exceeding a predetermined threshold occurs, and when the rainfall intensity at that time is expected to be maintained or further strengthened thereafter, control to open the gate of the storage facility May be performed. Thus, if the analysis results of the outflow analysis unit 106 and the inundation analysis unit 107 are used, a control device that controls the operation of the drainage facility in the diagnosis target area can be configured.

  The inundation risk diagnosis apparatus may be configured as a cloud system that distributes or provides the analysis result and the display of the analysis result (for example, an inundation hazard map) to an apparatus that can communicate via a network.

  According to at least one embodiment described above, an analysis model parameter generation unit 102 that generates parameters necessary for constructing an analysis model based on various quantities indicated by the flow rate calculation table in the diagnosis target area, and the flow rate calculation table indicate An analysis model construction unit 103 that constructs an analysis model based on various quantities and the above parameters, an outflow analysis unit 106 that calculates the flow rate of the pipeline in each small drainage area using the analysis model, and a calculation for each small drainage area. Inundation analysis unit 107 for calculating a full pipe ratio that is an index of inundation risk based on the flow rate of each pipeline, and in real-time inundation risk diagnosis in inundation risk diagnosis in the diagnosis target area It is possible to achieve both providing diagnostic results that are easy to understand for the user.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1,1a ... Inundation risk diagnostic apparatus, 101 ... Flow rate calculation table memory | storage part, 102 ... Analysis model parameter production | generation part, 103 ... Analysis model construction part, 104 ... Rainfall data acquisition part, 105 ... Pre-processing part, 106 ... Runoff analysis part DESCRIPTION OF SYMBOLS 106 ... Inundation analysis part 107 ... Inundation analysis part 108 ... Analysis result display part 109 ... Measurement data acquisition part 110 ... Analysis model parameter adjustment part 20 ... Diagnosis target area 21, 212-1-21-8 ... Junction point, 22, 22-1 to 22-7 ... Pipe line, 30 ... Selection display, 41, 41-1 to 41-8 ... Node, 100 ... Flow rate calculation table

Claims (11)

A parameter generation unit that generates parameters necessary for constructing an analysis model for diagnosing the inundation risk in the diagnosis target area based on various amounts indicated by the flow rate calculation table of the diagnosis target area;
An analysis model construction unit for constructing the analysis model based on the various quantities and the parameters;
Based on the analysis model constructed by the analysis model construction unit and the rainfall data acquired at a predetermined cycle for each small drainage area in the diagnosis target area, the flow rate for each pipeline in each small drainage area is calculated. An outflow analysis section
Based on the flow rate of each pipeline in each small drainage area calculated by the outflow analysis unit, an inundation analysis unit that calculates a full pipe rate for each pipeline serving as an index of the inundation risk of the small drainage zone;
Inundation risk diagnosis device comprising: The parameter generation unit calculates the flow velocity of the pipeline in a full pipe state or a semi-full pipe state, and calculates the flow down time that is one of the parameters by dividing the extension of the pipeline by the flow velocity.
The inundation risk diagnosis apparatus according to claim 1. The parameter generation unit calculates the downflow time by expressing the diameter depth and gradient in the Manning equation by the water level or the full pipe rate of the pipeline,
The inundation risk diagnosis device according to claim 2. The runoff analysis unit calculates an inflow time for each small drainage basin based on the flow time and the runoff time, and the runoff analysis is performed with a primary delay corresponding to the inflow time in the rainfall data for each small drainage basin. Do,
The inundation risk diagnosis device according to claim 2 or 3. A pre-processing unit that converts mesh rainfall data acquired for each predetermined mesh in the diagnosis target area into rainfall data for each small drainage area;
The inundation risk diagnosis device according to any one of claims 1 to 4. Based on the fullness ratio for each pipeline calculated by the inundation analysis unit, an analysis result for displaying the degree of inundation risk in the small drainage area on the map of the diagnosis target area in a visually identifiable manner A display unit,
The inundation risk diagnosis device according to any one of claims 1 to 5. A measurement information acquisition unit that acquires measurement information indicating the water level or flow rate from a measurement device that measures the water level or flow rate of any one or more pipelines connecting each small drainage area;
A parameter adjustment unit that adjusts the parameter so that an error between the flow rate or water level calculated by the outflow analysis and the flow rate or water level indicated by the measurement information is reduced;
Further comprising
The inundation risk diagnosis device according to any one of claims 1 to 6. The analysis result display unit transmits information on the inundation risk to another device connectable via a network.
The inundation risk diagnosis apparatus according to claim 6 or 7. A parameter generation step for generating parameters necessary for constructing an analysis model for diagnosing the inundation risk in the diagnosis target area based on various amounts indicated by the flow rate calculation table of the diagnosis target area;
An analytical model construction step of constructing the analytical model based on the various quantities and the parameters;
Based on the analysis model constructed by the analysis model construction unit and the rainfall data acquired at a predetermined cycle for each small drainage area in the diagnosis target area, the flow rate for each pipeline in each small drainage area is calculated. An outflow analysis step to
Based on the flow rate of each pipeline in each small drainage area calculated by the outflow analysis unit, an inundation analysis step of calculating a full pipe rate for each pipeline that serves as an index of inundation risk in the small drainage area;
A method for diagnosing inundation risk. A parameter generation step for generating parameters necessary for constructing an analysis model for diagnosing the inundation risk in the diagnosis target area based on various amounts indicated by the flow rate calculation table of the diagnosis target area;
An analytical model construction step of constructing the analytical model based on the various quantities and the parameters;
Based on the analysis model constructed by the analysis model construction unit and the rainfall data acquired at a predetermined cycle for each small drainage area in the diagnosis target area, the flow rate for each pipeline in each small drainage area is calculated. An outflow analysis step to
Based on the flow rate of each pipeline in each small drainage area calculated by the outflow analysis unit, an inundation analysis step of calculating a full pipe rate for each pipeline that serves as an index of inundation risk in the small drainage area;
A computer program for causing a computer to execute. A drainage facility in the diagnosis target area based on the outflow analysis result or the inundation analysis result in each small drainage area in the diagnosis target area acquired by the inundation risk diagnosis device according to any one of claims 1 to 8. Control the operation of the
Control device.

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