River channel underwater plane terrain reconstruction method and system based on section erosion and deposition and medium

Abstract

The invention relates to a river channel underwater plane terrain reconstruction method and system based on section erosion and deposition and a medium, and the method comprises the steps: collecting cross section and plane terrain observation data; calculating the erosion and deposition thickness of each node between the sections; regenerating a terrain change background grid between every two sections; and interpolating to form the underwater plane terrain of the river channel. According to the method, underwater topographic observation data of a plurality of measurement cross sections and a certain measurement are adopted, the plane topographic variation is formed by adopting river channel section erosion and deposition amplitude interpolation from comparison of erosion and deposition thicknesses of nodes of the multi-measurement cross sections, and underwater plane topographic data matched with section data are generated; the defect of underwater plane terrain observation data can be made up, the river bed erosion and deposition adjustment and evolution rule of a river channel can be reflected more accurately and fully, and a foundation support is provided for river planning and treatment.

Description

Technical Field

[0001] The present application relates to the field of water conservancy river sediment transport technology, and in particular to a method, system and medium for reconstructing underwater planar terrain of a river based on cross-section scouring and silting. Background Art

[0002] The underwater topography of the river channel has always been an important basis for riverbed evolution analysis and numerical simulation calculation of the river channel. However, due to the large workload, long time consumption and high cost of observation, the frequency of river channel topography is generally low. For important rivers such as the Yangtze River and the Yellow River, the frequency of measurement can only reach 2 to 3 years for key river sections and 5 years for non-key river sections. For small and medium-sized rivers, there is often a lack of riverbed plane topography observation data. In comparison, fixed section measurement is relatively simple and low-cost. For river sections with large changes, fixed sections with certain intervals can be selected for multiple observations within a year or at least once a year in the same period. The data has good continuity, but the fixed sections cannot reflect the changes in the riverbed throughout the process due to the large intervals, especially the continuous deformation of some key shoals and channels, and there are major shortcomings in the analysis of the river channel shoal and channel plane morphology.

[0003] In order to grasp the changing characteristics of the plane morphology of river shoals and troughs, enrich the content of riverbed evolution analysis, and fully grasp the basic laws of river channel evolution, this application uses multiple survey cross-sections and underwater topographic observation data of a certain survey. Starting from comparing the scouring and silting thickness of each node in multiple survey cross-sections, the scouring and silting amplitude of the river section is interpolated to form the change in plane topography. Based on the previous terrain and scouring and silting changes in time period, underwater plane topographic data matching the section data is generated to make up for the deficiency of underwater plane topographic observation data, and then more accurately and fully reflect the riverbed scouring and silting adjustment and shoal and channel pattern evolution law of the river channel, providing basic support for river planning and management. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a method, system and medium for reconstructing underwater plane topography of a river channel based on cross-sectional scouring and siltation, which can be applied to construct the plane topography of the second measurement when there are cross-sectional topography and plane topography from a first measurement, as well as cross-sectional data from a second measurement, to provide a basis for riverbed evolution analysis when measured plane topography data is scarce.

[0005] To achieve the above objectives, this application provides the following technical solutions:

[0006] In a first aspect, an embodiment of the present application provides a method for reconstructing underwater plane terrain of a river channel based on cross-section scouring and silting, comprising the following steps:

[0007] Step 1. Collect cross-sectional and planimetric topographic observation data;

[0008] Step 2. Calculate the scouring and silting thickness at each node between sections;

[0009] Step 3. Regenerate the background grid of terrain changes between two sections;

[0010] Step 4. Interpolate to form the underwater plane terrain of the river.

[0011] The implementation of step 1 is as follows:

[0012] Step 11. Collect the cross-sectional terrain data of the first and second measurements, including the starting distance of the measured nodes on the cross-sectional terrain. , Elevation :

[0013] ,

[0014] Among them, the subscript Indicates the measured value, is the number of the measured section, is the number of the measured node on the cross section, The number of measured sections, is the number of measured nodes on the cross section, and the subscripts 1 and 2 represent the first and second measurements, respectively.

[0015] Step 12. Collect the first measurement of plane terrain data, including the horizontal coordinates of the plane terrain measurement points , vertical coordinate , Elevation :

[0016] ,

[0017] in, is the number of the measured point of the plane terrain, is the number of measured points of plane terrain.

[0018] The implementation of step 2 is as follows:

[0019] Step 21. Set the number of new nodes on each section , whose value is the maximum value of the number of measured nodes of all cross-section terrain in the cross-section terrain data of two measurements, subscript Indicates the new node to be set.

[0020] Step 22. Determine the minimum distance between the starting points of the two measured nodes of the cross-section terrain , maximum value ,

[0021] Step 23. According to , , set the starting distance of the new node on the section :

[0022] ,

[0023] Step 24. Use linear interpolation to generate the elevation of each new node on the two measurement sections:

[0024] ,

[0025] Among them, the cross section The new node is located on the cross section and Between the measured nodes,

[0026] Step 25. Calculate the scouring and silting thickness between two measurements for each new node on the cross section:

[0027] .

[0028] The implementation of step 3 is as follows:

[0029] Step 31. Calculate the horizontal coordinates of each new node on the cross section and the vertical coordinate :

[0030] ,

[0031] in, and Represent the horizontal and vertical coordinates of the cross section, respectively. Indicates the starting point, Indicates the end point,

[0032] Step 32. First, connect the first A new node is created to generate a quadrilateral background mesh, and then the first node of one of the sections is connected. A new node and another section A new node is created to generate a triangular background mesh.

[0033] The implementation of step 4 is as follows:

[0034] Step 41. Select any triangle in the triangular background grid and use Heron's formula to calculate the area of ​​the triangle :

[0035] ,

[0036] in, are the three side lengths of the triangle, is half the sum of the three sides.

[0037] Step 42. Connect the measured points of the first survey plane topography with any two points of the triangle to form three new triangles. Apply Heron's formula again to calculate the areas of the three new triangles. , , ,

[0038] Step 43. Judgement Whether , , If the sum is not equal, select other triangles in the background grid in turn until the triangle where the measured point of the plane terrain of the first measurement is located is found.

[0039] Step 44. Based on the coordinates of the three vertices of the triangle where the measured point of the plane terrain of the first measurement is located and the scouring and silting thickness, the inverse distance interpolation method is used to interpolate the scouring and silting thickness of the measured point of the plane terrain of the first measurement:

[0040] ,

[0041] in, is the scouring thickness at the triangle vertex, is the distance from the measured point of the plane terrain to the vertex of the triangle in the first measurement.

[0042] Step 45. Calculate the terrain elevation of the second measured plane terrain point:

[0043] .

[0044] In a second aspect, an embodiment of the present application provides a river underwater plane terrain reconstruction system based on cross-section scouring and silting, comprising:

[0045] Data collection module, used to collect observation data of fixed sections of river sections and underwater topography;

[0046] Scouring and silting thickness calculation module, used to cut encrypted sections based on terrain observation data;

[0047] Plane mesh regeneration module, used to regenerate plane terrain interpolation calculation mesh;

[0048] The terrain interpolation calculation module is used to calculate the new planar underwater terrain of the river by difference.

[0049] In a third aspect, an embodiment of the present application provides a computer-readable storage medium, which stores program code. When the program code is executed by a processor, the steps of the method for reconstructing underwater planar topography of a river channel based on cross-sectional scouring and siltation are implemented as described above.

[0050] Compared with the prior art, the beneficial effects of the present application are as follows: the present application adopts multiple survey cross-sections and underwater topographic observation data of a certain survey, starts from comparing the scouring and silting thickness of each node of the multiple survey cross-sections, and adopts the interpolation of the scouring and silting amplitude of the river section to form the plane topographic change, thereby generating underwater plane topographic data that matches the section data, which can make up for the deficiency of underwater plane topographic observation data, and then more accurately and fully reflect the riverbed scouring and silting adjustment and evolution law of the river channel, and provide basic support for river planning and management. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0052] Figure 1 A flow chart of the method of the embodiment of the present application;

[0053] Figure 2 Two cross-sectional topographic maps and one plane topographic map of a river section in a river basin where shoals and channels coexist in an embodiment of the present application;

[0054] Figure 3 The cross-section scouring and silting distribution diagrams of two measurements in the embodiment of the present application;

[0055] Figure 4 A background grid diagram between two sections in an embodiment of the present application;

[0056] Figure 5 The scouring and silting thickness between two measurements calculated by the embodiment of the present application and the topography of the second measurement, as well as the measured scouring and silting thickness map;

[0057] Figure 6 This is a system block diagram of an embodiment of the present application. DETAILED DESCRIPTION

[0058] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0059] The terms "comprises," "comprising," or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0060] The terms "first", "second", etc. are only used to distinguish one entity or operation from another entity or operation, and should not be understood as indicating or implying relative importance, nor should they be understood as requiring or implying any such actual relationship or order between these entities or operations.

[0061] Reference Figure 1 The present application embodiment provides a method for reconstructing underwater plane terrain of a river channel based on cross-section scouring and silting, comprising the following steps:

[0062] Step 1. Collect the cross-sectional topographic and planar topographic data of the first survey and the cross-sectional topographic data of the second survey;

[0063] Step 2. construct the distribution of new nodes on the cross section, and calculate the scouring and silting thickness between two cross-section topographic measurements of the new nodes on the cross section;

[0064] Step 3. Generate a background grid based on the new node distribution on the cross section;

[0065] Step 4. Interpolate the second measurement plane topography based on the scouring and silting thickness of the background grid nodes and the measured points of the first measurement plane topography.

[0066] The implementation of step 1 is as follows:

[0067] Step 11. Collect the cross-sectional terrain data of the first and second measurements, including the starting distance of the measured nodes on the cross-sectional terrain. , Elevation :

[0068] ,

[0069] Among them, the subscript Indicates the measured value, is the number of the measured section, is the number of the measured node on the cross section, The number of measured sections, is the number of measured nodes on the cross section, and the subscripts 1 and 2 represent the first and second measurements, respectively.

[0070] Step 12. Collect the first measurement of plane terrain data, including the horizontal coordinates of the plane terrain measurement points , vertical coordinate , Elevation :

[0071] ,

[0072] in, is the number of the measured point of the plane terrain, is the number of measured points of plane terrain.

[0073] The implementation of step 2 is as follows:

[0074] Step 21. Set the number of new nodes on each section , whose value is the maximum value of the number of measured nodes of all cross-section terrain in the cross-section terrain data of two measurements, subscript Indicates the new node to be set.

[0075] Step 22. Determine the minimum distance between the starting points of the two measured nodes of the cross-section terrain , maximum value ,

[0076] Step 23. According to , , set the starting distance of the new node on the section :

[0077] ,

[0078] Step 24. Use linear interpolation to generate the elevation of each new node on the two measurement sections:

[0079] ,

[0080] Among them, the cross section The new node is located on the cross section and Between the measured nodes,

[0081] Step 25. Calculate the scouring and silting thickness between two measurements for each new node on the cross section:

[0082] .

[0083] The implementation of step 3 is as follows:

[0084] Step 31. Calculate the horizontal coordinates of each new node on the cross section and the vertical coordinate :

[0085] ,

[0086] in, and Represent the horizontal and vertical coordinates of the cross section, respectively. Indicates the starting point, Indicates the end point,

[0087] Step 32. First, connect the first A new node is created to generate a quadrilateral background mesh, and then the first node of one of the sections is connected. A new node and another section A new node is created to generate a triangular background mesh.

[0088] The implementation of step 4 is as follows:

[0089] Step 41. Select any triangle in the triangular background grid and use Heron's formula to calculate the area of ​​the triangle :

[0090] ,

[0091] in, are the three side lengths of the triangle, is half the sum of the three sides.

[0092] Step 42. Connect the measured points of the first survey plane topography with any two points of the triangle to form three new triangles. Apply Heron's formula again to calculate the areas of the three new triangles. , , ,

[0093] Step 43. Judgement Whether , , If the sum is not equal, select other triangles in the background grid in turn until the triangle where the measured point of the plane terrain of the first measurement is located is found.

[0094] Step 44. Based on the coordinates of the three vertices of the triangle where the measured point of the plane terrain of the first measurement is located and the scouring and silting thickness, the inverse distance interpolation method is used to interpolate the scouring and silting thickness of the measured point of the plane terrain of the first measurement:

[0095] ,

[0096] in, is the scouring thickness at the triangle vertex, is the distance from the measured point of the plane terrain to the vertex of the triangle in the first measurement.

[0097] Step 45. Calculate the terrain elevation of the second measured plane terrain point:

[0098] .

[0099] The specific steps of the embodiment are as follows:

[0100] Step 1. Collect topographic data of eight sections from two surveys and one plane topographic data from one survey of a river section where both shoals and deep troughs exist in a certain river basin (e.g. Figure 2 as shown).

[0101] Step 2. The maximum number of nodes measured in the two cross-sectional terrain measurements collected is 244, so the number of new nodes on each cross-sectional area is proposed to be 244. Take the maximum and minimum values ​​of the measured starting point distances of each cross-sectional area, set each node to be evenly distributed on the cross-sectional area, and calculate the starting point distance of each new node. Use the linear interpolation method to calculate the scouring and silting thickness between the two measurements of each new node on the cross-sectional area. Figure 3 shown.

[0102] Step 3. After calculating the coordinates of the new node on the section according to the coordinates of the starting and ending points of the section, first connect the first nodes on two adjacent sections. A new node is created to generate a quadrilateral background mesh, and then the first node of one of the sections is connected. A new node and another section A new node is generated to generate a triangular background mesh, where the triangular background mesh formed between section 1 and section 2 is as follows: Figure 4 shown.

[0103] Step 4. For the first measured point of the plane terrain to be interpolated, select any triangle in the background grid and first apply Heron's formula to calculate the area of ​​the triangle , then calculate the area of ​​three new triangles formed by the measured point of the plane terrain and any two points of the triangle ,judge Whether

[0104] If the sum is equal, then select other triangles in the background grid in turn until the triangle where the plane topography measured point of the first measurement is located is found. Use the inverse distance interpolation method to interpolate the erosion and siltation thickness of the plane topography measured point of the first measurement, and finally calculate the terrain elevation of the plane topography point of the second measurement. The result is as follows: Figure 5As shown in the figure, the comparison with the measured values ​​shows that the distribution law of scouring and silting thickness calculated by this method is basically consistent with the measured values, which can reflect the distribution law of scouring and silting between the shoals and channels.

[0105] The embodiment of the present application provides an improved system for calculating riverbed scouring and silting volume based on terrain classification and densification, comprising:

[0106] Data collection module 1, used to collect fixed section and underwater topographic observation data of river sections;

[0107] Scouring and silting thickness calculation module 2, used to cut encrypted sections based on terrain observation data;

[0108] A plane grid regeneration module 3 is used to regenerate a plane terrain interpolation calculation grid;

[0109] The terrain interpolation calculation module 4 is used to calculate the new planar underwater terrain of the river channel by difference.

[0110] An embodiment of the present application provides a computer-readable storage medium, which stores program codes. When the program codes are executed by a processor, the steps of the method for reconstructing underwater planar terrain of a river channel based on cross-section scouring and siltation are implemented as described above.

[0111] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0112] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0113] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0114] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0115] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0116] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0117] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0118] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for reconstructing underwater plane terrain of a river channel based on cross-section scouring and silting, characterized in that: The following steps are involved: Step 1. Collect cross-sectional and planimetric topographic observation data; Step 2. Calculate the scouring and silting thickness at each node between sections; Step 3. Regenerate the background grid of terrain changes between two sections; Step 4. Interpolate to form the underwater plane terrain of the river.

2. The method for reconstructing underwater plane terrain of a river channel based on cross-section scouring and silting according to claim 1 is characterized in that: The implementation of step 1 is as follows: Step 11. Collect the cross-sectional terrain data of the first and second measurements, including the starting distance of the measured nodes on the cross-sectional terrain. , Elevation : ， Among them, the subscript Indicates the measured value, is the number of the measured section, is the number of the measured node on the cross section, The number of measured sections, is the number of measured nodes on the cross section, and the subscripts 1 and 2 represent the first and second measurements, respectively. Step 12. Collect the first measurement of plane terrain data, including the horizontal coordinates of the plane terrain measurement points , vertical coordinate , Elevation : ， in, is the number of the measured point of the plane terrain, is the number of measured points of plane terrain.

3. The method for reconstructing underwater plane terrain of a river channel based on cross-section scouring and silting according to claim 1 is characterized in that: The implementation of step 2 is as follows: Step 21. Set the number of new nodes on each section , whose value is the maximum value of the number of measured nodes of all cross-section terrain in the cross-section terrain data of two measurements, subscript Indicates the new node to be set. Step 22. Determine the minimum distance between the starting points of the two measured nodes of the cross-section terrain , maximum value , Step 23. According to , , set the starting distance of the new node on the section : ， Step 24. Use linear interpolation to generate the elevation of each new node on the two measurement sections: ， Among them, the cross section The new node is located on the cross section and Between the measured nodes, Step 25. Calculate the scouring and silting thickness between two measurements for each new node on the cross section: 。 4. The method for reconstructing underwater plane terrain of a river channel based on cross-section scouring and silting according to claim 1 is characterized in that: The implementation of step 3 is as follows: Step 31. Calculate the horizontal coordinates of each new node on the cross section and the vertical coordinate : ， in, and Represent the horizontal and vertical coordinates of the cross section, respectively. Indicates the starting point, Indicates the end point, Step 32. First, connect the first A new node is created to generate a quadrilateral background mesh, and then the first node of one of the sections is connected. A new node and another section A new node is created to generate a triangular background mesh.

5. The method for reconstructing underwater plane terrain of a river channel based on cross-section scouring and silting according to claim 1 is characterized in that: The implementation of step 4 is as follows: Step 41. Select any triangle in the triangular background grid and use Heron's formula to calculate the area of ​​the triangle : ， in, are the three side lengths of the triangle, is half the sum of the three sides. Step 42. Connect the measured points of the first survey plane topography with any two points of the triangle to form three new triangles. Apply Heron's formula again to calculate the areas of the three new triangles. , , , Step 43. Judgement Whether , , If the sum is not equal, select other triangles in the background grid in turn until the triangle where the measured point of the plane terrain of the first measurement is located is found. Step 44. Based on the coordinates of the three vertices of the triangle where the measured point of the plane terrain of the first measurement is located and the scouring and silting thickness, the inverse distance interpolation method is used to interpolate the scouring and silting thickness of the measured point of the plane terrain of the first measurement: ， in, is the scouring thickness at the triangle vertex, is the distance from the measured point of the plane terrain to the vertex of the triangle in the first measurement. Step 45. Calculate the terrain elevation of the second measured plane terrain point: 。 6. A river underwater plane terrain reconstruction system based on cross-section scouring and silting, characterized in that: include, Data collection module, used to collect observation data of fixed sections of river sections and underwater topography; Scouring and silting thickness calculation module, used to cut encrypted sections based on terrain observation data; Plane mesh regeneration module, used to regenerate plane terrain interpolation calculation mesh; The terrain interpolation calculation module is used to calculate the new planar underwater terrain of the river by difference.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores program codes, and when the program codes are executed by a processor, the steps of the method for reconstructing underwater planar terrain of a river channel based on cross-section scouring and silting are implemented as described in any one of claims 1 to 5.

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