A quick method for establishing the relationship among storage, inundated area and water level of a dammed lake

Abstract

The application discloses a dammed lake storage-capacity-submergence-area-water level relationship quick construction method and device and a storage medium, and belongs to the technical field of water conservancy engineering disaster emergency management. The method of the application collects a topographic map to construct a DEM of a dammed lake region, and then intersects the DEM with a dam top elevation plane to generate a maximum lake body model, and performs scale self-adaptive three-dimensional grid discretization on the model and calculates grid parameters; subsequently, the water level is traversed according to a set step length within the range of the dammed body river bottom and top elevation, the submergence area top surface boundary grid body and all submergence grid bodies are respectively counted, the submergence area and the storage capacity corresponding to the water level are calculated, and finally, the relationship curves of the two and the water level are generated. The application only needs a conventional topographic map, does not need complex hydrological parameters, has high modeling efficiency and low operation threshold, balances the calculation accuracy and efficiency, adapts to the quick judgment and analysis needs of dammed lake emergency rescue, has wide applicability and high popularization value.

Description

Technical Field

[0001] This invention belongs to the field of emergency management technology for water conservancy engineering disasters, and specifically relates to a rapid method for constructing the relationship between reservoir capacity, inundation area, and water level of a landslide dammed lake. It is applicable to hydrological situation analysis, inundation risk assessment, and emergency response decision support in the emergency response to landslide dammed lakes. Background Technology

[0002] A landslide-dammed lake is a natural reservoir formed when landslides or collapses, triggered by natural disasters such as earthquakes or torrential rains, block river channels. Once it breaches, a massive volume of water is released in a short period, creating a highly destructive flood that seriously threatens the lives and property of people downstream and the safety of critical infrastructure. In emergency response to high-risk landslide-dammed lakes, rapidly and accurately obtaining the reservoir capacity-inundation area-water level relationship is crucial for predicting the scale of the breach flood, assessing the upstream inundation range, simulating the downstream flood path, and developing evacuation plans.

[0003] Currently, the construction of the reservoir capacity-inundation area-water level relationship for landslide-dammed lakes mainly relies on traditional hydrological methods or high-precision topographic data. Traditional hydrological methods combine watershed confluence simulation with river backwater calculation. While theoretically mature, these methods have high professional barriers and require numerous parameters, such as river roughness, gradient, and cross-sectional morphology. This makes them difficult to apply quickly in emergency scenarios where data is scarce and time is tight. Furthermore, landslide-dammed lakes often form in complex, inaccessible mountainous and canyon areas, making on-site surveying difficult and hindering the rapid acquisition of high-precision digital elevation models (DEMs) covering the upstream inundation area. This makes detailed modeling methods based on high-precision DEMs difficult to implement in actual disaster relief. Therefore, existing technologies generally suffer from strong parameter dependence and long modeling cycles, failing to meet the need for rapid construction of the reservoir capacity-inundation area-water level relationship in landslide-dammed lake emergency response. There is an urgent need to develop a method that uses limited and readily available topographic data and efficient data processing algorithms to rapidly construct this relationship, providing support for emergency response decision-making. Summary of the Invention

[0004] This invention aims to overcome the shortcomings of existing technologies and solve the technical problems of strong dependence on hydrological parameters, high requirements for high-precision topographic data, and complex and time-consuming modeling process when constructing the relationship between reservoir capacity, inundation area, and water level of landslide dammed lakes. It provides a method that, based on easily accessible topographic maps, constrains river topographic features, and uses a gridded statistical model to quickly and automatically generate reliable curves for the relationship between reservoir capacity, inundation area, and water level, thus meeting the need for rapid assessment of key hydrological situation data in emergency rescue operations for landslide dammed lakes.

[0005] To achieve the above objectives, the technical solution of this invention is as follows: This paper utilizes GIS surveying equipment to perform a complete pipeline processing of field-measured topographic data of landslide-dammed lakes. This addresses the technical challenges of limited topographic data during emergency rescue operations, the time-consuming nature of traditional hydrological modeling, and the repetitive calculation of inundation area in grid-based statistical methods. The process balances modeling efficiency and computational accuracy, and includes the following steps: 1) Topographic data acquisition and constrained DEM generation steps: Collect measured topographic maps of the landslide dammed lake area, extract the river centerline, left and right boundaries of the river channel, and riverbank topographic vector lines to construct a constrained vector library, and simultaneously collect measured crest elevations of the landslide dam body. Riverbed elevation The GIS processor calls the TIN irregular triangular network interpolation module to generate a digital elevation model of the upstream river channel using vector feature lines as terrain constraints. (x,y), where (x,y) are planar coordinates; 2) Based on the digital elevation model obtained in step 1) (x,y) Constructing the largest lake model of the landslide dammed lake: In the 3D modeling environment, define a plane model S of the dam crest elevation, where the plane model S is expressed as z= Where z is the elevation coordinate in three-dimensional space; the digital elevation model The intersection of (x,y) with the space below the dam crest elevation plane S is used to generate the largest lake model of the landslide dammed lake. ; 3) The largest lake model obtained in step 2) 3D mesh discretization: The largest lake model is discretized using mesh generation techniques. Divide the grid into N meshes and calculate the projected area of ​​each mesh. ,volume and center point coordinates ( , , ); 4) Hardware calculation steps for flooded area: The processor reads the water level range [ , [and traversal step size] H ,in The elevation of the riverbed at the location of the landslide dam. The elevation of the top of the landslide dam. = , with step size H Traverse any water level within the water level calculation range Statistical satisfaction of center point elevation ≤ and( - The value is the total number of mesh cells with the minimum difference. Calculate the current water level The submerged area After traversing all water levels, a series of points relating the water level and inundated area of ​​the landslide dam lake are generated and connected to form a curve. 5) Based on the grid parameters obtained in step 3) and the water level parameters set in step 4), construct a water level-reservoir capacity calculation model and generate a relationship curve: using the water level calculation range set in step 4) [ , and water level step H Traverse any water level Statistical satisfaction of center point elevation ≤ Total number of grid cells Calculate the current water level Under storage capacity After traversing all water levels, a series of points on the water level-reservoir capacity relationship of the landslide dam lake are generated, and then connected to form a curve; Output the water level-inundation area relationship curve obtained in step 4) and the water level-reservoir capacity relationship curve obtained in step 5) to the landslide dam emergency response terminal for engineering assessment of downstream inundation range, flood scale, and personnel evacuation plan.

[0006] Furthermore, the construction of the digital elevation model (DEM) of the landslide dammed lake area includes collecting topographic maps of the area and confirming their scale, and extracting the river centerline from the topographic maps. L The left and right boundary lines of the river channel and Topographic lines on the left and right banks of the river and This creates a vector database and simultaneously obtains the elevation of the top of the landslide dam. and the riverbed elevation at the landslide dam Using a vector database as terrain constraints, a digital elevation model of the upstream river channel area of ​​the landslide dammed lake was generated by performing elevation interpolation using GIS software and the TIN irregular triangular network algorithm. (x,y).

[0007] Furthermore, for the aforementioned largest lake model The 3D mesh discretization process involves determining the mesh generation accuracy according to a set topographic map scale. Specifically, when the topographic map scale is greater than or equal to 1:5000, the mesh planar dimensions Δx = Δy = 0.5m; when the scale is greater than 1:10000 but less than 1:5000, the mesh planar dimensions Δx = Δy = 1.0m; and when the scale is less than or equal to 1:10000, the mesh planar dimensions Δx = Δy = 2.0m. All meshes have the same vertical height Δz. Based on the determined Δx, Δy, and Δz, the lake model with the largest possible size is then created. Cut into N meshes, mesh The geometric parameter characteristics are shown in equation (2): Equation (2) In the formula: For mesh Projected area; For mesh volume; For mesh center point , , Center point The coordinate values.

[0008] Furthermore, the grid cell with the minimum difference is the grid cell located at the top boundary of the flooded area.

[0009] Furthermore, the current water level The submerged area The calculation is shown in equation (3): Equation (3) In the formula: For the current calculated water level The submerged area of ​​the lower landslide dammed lake; Current water level The center point elevation is satisfied ≤ And the total number of mesh cells with the smallest difference; Let i be the planar projected area of ​​the i-th qualified mesh body; This is a function that outputs 1 if the condition within the parentheses is met, and 0 otherwise. Let the elevation be the center point elevation of the i-th grid cell; For a given water level value calculated through iteration, and ∈[ , ].

[0010] Furthermore, the current water level Under storage capacity The calculation is shown in equation (4): Equation (4) In the formula: For the current calculated water level The reservoir capacity of the landslide-dammed lake; Current water level The following satisfies ≤ The total number of grid cells; For the first Volume of a conditional mesh volume; function Indicates when the condition is met ≤ If a condition is met, the function returns 1; otherwise, it returns 0. Let be the elevation of the center point of the i-th grid cell.

[0011] This invention discloses a device comprising at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to execute the method for rapidly constructing the relationship between the reservoir capacity, inundation area, and water level of a landslide dammed lake.

[0012] The present invention also discloses a computer-readable storage medium storing a computer program, which, when executed by a processor, implements a method for rapidly constructing the relationship between the reservoir capacity, inundation area, and water level of the landslide dammed lake.

[0013] The method for rapidly constructing the relationship between reservoir capacity, inundated area, and water level of a landslide-dammed lake proposed in this invention has the following significant advantages compared to existing technologies: 1. This invention proposes a complete rapid construction technology system based on vector constraints and grid statistics. It can quickly generate the relationship curve from topographic data to reservoir capacity-inundated area-water level using only easily obtainable topographic maps. This solves the problems of many parameters and slow modeling in traditional methods and meets the time urgency requirements of landslide dammed lake emergency rescue.

[0014] 2. By constructing a DEM using river channel topographic feature lines as constraints, the simulation accuracy of key topographic features in the upstream river channel was ensured. At the same time, the adoption of a grid discretization algorithm that adapts to the topographic map scale improved the processing efficiency of large-scale topographic data, effectively balancing the contradiction between computational accuracy and processing efficiency.

[0015] 3. The model has a clear principle and standardized operation process, which does not require operators to have in-depth hydrological knowledge, greatly reducing the dependence on professional level. This allows non-hydrological engineering personnel to operate quickly and generate reliable results even in tense emergency rescue environments.

[0016] 4. It is applicable to topographic data of different scales and can be adapted to landslide dams of different sizes and topographic conditions, providing a universal and efficient technical tool for emergency response to landslide dams. It has important engineering application value and broad prospects for promotion. Attached Figure Description

[0017] Figure 1 is a schematic diagram of the overall process of the method of the present invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only some, not all, of the embodiments of this invention, and are not intended to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0019] The method for rapidly constructing the relationship between reservoir capacity, inundated area, and water level of a landslide-dammed lake according to the present invention includes the following steps: 1) Construct a regional DEM of the upstream river channel of the landslide dammed lake. Collect topographic maps of the landslide-dammed lake area and confirm their scale, then extract the river centerline from the topographic maps. L The left and right boundary lines of the river channel and and the topographic lines on the left and right banks of the river. and This forms a vector database. Simultaneously, the elevation of the top of the landslide dam is obtained through data retrieval or simple on-site measurements. and the riverbed elevation at the landslide dam Using the aforementioned vector database as terrain constraints, and employing GIS software or a custom program, an elevation interpolation algorithm based on TIN (Triangulated Irregular Network) is used to generate a digital elevation model of the upstream river channel area of ​​the landslide dammed lake. The model, denoted by (x, y), represents the planar coordinates of the upstream river channel. This model provides a digital representation of the upstream river channel topography, offering a reliable digital foundation for subsequent calculations.

[0020] This invention specifies the extraction of four types of feature lines from the topographic map of the landslide dammed lake area: the river centerline, the left and right boundary lines of the river channel, and the topographic lines of the left and right banks of the river, forming a vector database. This clarifies the basic data type and source for DEM construction. The vector database serves as a topographic constraint, defining the spatial range and topographic boundaries of the DEM construction, avoiding the ambiguity of unconstrained modeling. The invention explicitly employs the TIN (Triangulated Irregular Network) algorithm for elevation interpolation, implemented through GIS software or a custom program, specifying the algorithm and providing a practical implementation method. The generated digital elevation model (DEM) is defined as a function... (x,y) clarifies the mathematical expression and output form of the model, providing a digital foundation for subsequent lake model construction. The TIN algorithm is a common algorithm for constructing digital elevation models in the field of geographic information, and will not be elaborated here. The GIS software used in the specific implementation of this invention, such as ArcGIS and QGIS, all have built-in TIN algorithm elevation interpolation functions. By using the extracted vector feature lines as constraints through GIS software, the generation of the DEM for the river area can be realized.

[0021] 2) Construct a model of the maximum possible size of the landslide dammed lake. In the 3D modeling environment, define the plane model S of the dam crest elevation: z = The planar model of the dam crest elevation is defined as S, and the mathematical expression for this plane is z = ,in The elevation of the top of the landslide dam is determined. Through three-dimensional Boolean operations, the intersection of the constructed DEM model with the space below the dam crest elevation plane S is calculated to generate the model of the largest possible lake size of the landslide dammed lake. Precisely define the maximum spatial extent of the lake. Maximum lake model. The model can be mathematically defined as equation (1): ={(x,y , z)∣(x,y , z) River channel horizontal range, z Equation (1) The three-dimensional spatial set representing the maximum possible lake size model of the landslide dammed lake represents the maximum water storage space range that the landslide dammed lake can form; (x,y) represents the plane coordinates, and (x,y) is limited to the plane range of the river channel upstream of the landslide dam, defined by the extracted river centerline and the left and right boundary lines of the river channel; z represents the elevation coordinate in three-dimensional space, i.e., the vertical coordinate. This represents the top elevation of the landslide dam, which is the highest elevation constraint of the lake model. If the water level exceeds this value, the landslide dam will overflow. (x,y) represents the constructed digital elevation model of the upstream river channel area of ​​the landslide dammed lake, which serves as the topographic bottom elevation constraint for the lake model. The lake space is formed based on the actual river channel topography and must not be lower than the river channel topographic elevation.

[0022] Formula 1 mathematically defines the three-dimensional spatial boundary of the potential maximum lake model of the landslide dammed lake. Formula 1 indicates that the potential maximum lake model of the landslide dammed lake is a three-dimensional spatial region above the river channel topographic elevation and below the top elevation of the landslide dam. Essentially, it filters out the water-storage space within the river channel topographic range and below the top elevation of the landslide dam through dual constraints of planar range and elevation. This completely corresponds to the three-dimensional Boolean intersection operation between the DEM model and the space below the top elevation plane S in step 2), and is the mathematical quantitative expression of this three-dimensional Boolean intersection operation. It also provides a clear spatial range basis for the subsequent mesh discretization of the maximum lake model.

[0023] Formula S:z= This means that the plane containing the crest of the landslide dam is a horizontal plane with a constant elevation, and the elevation coordinate z of all spatial points on this plane is equal to the elevation of the crest of the landslide dam. . The elevation plane S, which is the actual measured or acquired top elevation of the landslide dam, represents the maximum elevation boundary that the water level of the landslide dammed lake can reach. If the water level exceeds this plane, it will overflow the landslide dam. Therefore, the elevation plane S is used to define the model of the potentially largest lake. In this invention, by performing a three-dimensional Boolean intersection between the elevation plane S and the DEM model, all elevation coordinates z ≤ in the DEM model can be filtered out. The spatial region refers to the river channel topography below the crest elevation of the dam, which represents the maximum lake area that a landslide dammed lake can form. The elevation coordinates of z form the basis for this spatial filtering.

[0024] 3) Discretization of the three-dimensional mesh for the largest lake model To balance computational efficiency and accuracy, the grid division accuracy is determined based on the previously confirmed topographic map scale. When the topographic map scale is greater than or equal to 1:5000, the grid division plane dimension is set to Δx=Δy=0.5m; when the topographic map scale is greater than 1:10000 and less than 1:5000, the grid division plane dimension is set to Δx=Δy=1.0m; when the topographic map scale is less than or equal to 1:10000, the grid division plane dimension is set to Δx=Δy=2.0m; the grid division height dimension is Δz=1m for all grids. Based on the above determined Δx=Δy and Δz... ， The largest lake model Divide the material into N meshes and calculate the value of each mesh. Geometric parameters: Projected area: (Unit: m) 2 ),volume (Unit: m) 3 ) and center point coordinates ( , , ). Mesh The geometric parameter characteristics are shown in equation (2): Equation (2) In the formula: For mesh The projected area is the planar projected area of ​​the i-th qualified mesh cell, in meters. 2 ; For mesh volume; For mesh center point , , Center point The coordinate values.

[0025] 4) Construct a water level-inundated area calculation model based on grid statistics and generate relationship curves. The water level calculation range is set as [ , ],in The elevation of the riverbed at the location of the landslide dam. The elevation of the top of the landslide dam. = At the same time, set the water level step size. H , H The preferred step size is 1m, which can be adjusted according to accuracy requirements; the step size is... H Traverse any water level within the water level calculation range , ∈[ , Only those centers with elevations lower than [the specified value] are counted. And the elevation of the center point and The difference is the minimum total number of grid cells. This type of grid cell represents the top boundary grid cell of the flooded area below the current water level. ≤ The total number of mesh cells with the smallest difference is denoted as . Dynamically calculate the submerged area below this water level. As shown in equation (3); after traversing all water levels, a series of points on the relationship between the water level and the submerged area of ​​the landslide dam lake are generated and connected to form a smooth curve.

[0026] Equation (3) The above model guarantees that at the current water level Below, only those centers with elevations lower than [the specified value] are counted. And the grid with the smallest difference.

[0027] In the formula: This is a function that outputs 1 if the condition within the parentheses is met, and 0 otherwise. For example, the function... It means that when the condition is met ≤ The function returns 1 if a condition is met, otherwise it returns 0. For the current calculated water level The submerged area of ​​the lower landslide dammed lake (unit: m) 2 ); Current water level The center point elevation is satisfied ≤ And the total number of mesh cells with the smallest difference; The planar projected area of ​​the i-th satisfying grid cell (unit: m²) 2 ); Elevation of the center point of the i-th grid cell (in meters); For a given water level value (unit: m) calculated through iteration, and ∈[ , ], The elevation of the riverbed at the location of the landslide dam. The elevation of the top of the landslide dam is given. The minimum difference, combined with the fixed design of a grid vertical height Δz = 1m in this method, is quantified as the elevation of the grid center point satisfying the following condition. -Δz< ≤ Right now -1m< ≤ This type of mesh represents the top boundary mesh of the inundated area below the current water level. Statistical analysis of only this type of mesh avoids redundant calculations of the projected area caused by overlapping multiple meshes, ensuring the calculation results closely match the actual inundated area of ​​the landslide dammed lake. As one embodiment, Δz can be equal to... H .

[0028] In this invention, the minimum difference refers to the elevation of the center point of the grid. Compared with the current calculated water level elevation difference ( - ) is the smallest, and is limited ≤ If the elevation of the center point is lower than or equal to the current water level, then the current water level can be calculated. The grid cells at the submerged boundary are used to accurately calculate the actual submerged area corresponding to that water level. The formula for calculating the difference is: Difference = - , Elevation of the center point of the grid. The current calculated water level; only those simultaneously meeting the criteria are counted. ≤ That is, the submerged grid cells with the minimum difference at their center point are excluded, and all submerged grid cells with larger differences are excluded. Since the grid height dimension Δz is set to 1m, meaning all grid cells have a uniform vertical height, the actual minimum difference is 0 ≤ minimum difference ≤ 1m. The vertical height of the grid cells determines that the maximum elevation difference does not exceed 1m, which is a reasonable constraint that fits the model's grid discretization design. (Reservoir capacity calculation and statistics are all included.) ≤ The total submerged volume is calculated by summing the volumes of the grid cells, regardless of their positions within the submerged space; the submerged area calculation only considers the cells with the smallest difference. ≤ The grid cells, summing their projected areas This calculates the actual planar area of ​​the landslide dammed lake surface in contact with the terrain at the current water level, i.e., the boundary outline area of ​​the inundated area. All submerged grid cells constitute the inundation space of the landslide dammed lake, corresponding to the reservoir capacity. The grid cell with the smallest difference is precisely the top boundary of this inundation space, and its projected area is the actual inundated area at the current water level. This invention cuts the largest lake model into regular three-dimensional grid cells. These grid cells are discrete rather than continuous terrain. If the projected area of ​​all submerged grid cells is directly calculated, problems such as double-counting of areas and large deviations from the actual water surface area will occur, such as multiple layers of grid overlapping, resulting in multiple accumulation of projected areas. The minimum difference is determined by extracting the grid cell that exactly matches the current water level from the discrete grid cells. That layer of mesh, whose projected area closely matches the actual inundation area of ​​the landslide dammed lake, avoids redundant calculations and is compatible with the mesh discretization model design, achieving a balance between computational efficiency (mesh statistics) and computational accuracy (fitting the actual inundation boundary). For example, assuming the current calculated water level... =100m, grid Δz=1m, there are three types of submerged grid cells: Type 1 mesh: =99.5m, the difference =0.5m, is the minimum difference, corresponding to the boundary grid of the top surface of the flooded area; Type 2 grid: =99m, difference =1m; Type 3 grid: =98m, difference =2m.

[0029] The inundation area calculation only considers the first type of grid, i.e., all grids that satisfy the condition. ≤ The grid cell with the smallest difference, when summed, has the projected area of ​​the first type of grid. =100m inundation area; while reservoir capacity calculation statistics include all Class 1 grids plus Class 2 grids plus Class 3 grids, which is all those that satisfy... ≤ The volume of the grid is the sum of the volumes of the first type of grid, the second type of grid, and the third type of grid.

[0030] 5) Construct a water level-reservoir capacity calculation model based on grid statistics. Based on the water level calculation range set in step 4) , and step size H , with step size H Traversing any water level Calculate the elevation of all center points ≤ Total number of grid cells As shown in equation (4), the reservoir capacity at this water level is dynamically calculated. After traversing all water levels, a series of points representing the water level-reservoir capacity relationship of the landslide dam lake are generated, and these points are connected to form a smooth curve, thus generating the water level-reservoir capacity curve of the landslide dam lake.

[0031] Equation (4) In the formula: For the current calculated water level The reservoir capacity of the lower landslide dammed lake (unit: m) 3 ); Current water level The following satisfies ≤ The total number of grid cells; For the first Volume of a qualified grid cell (unit: m) 3 );function It means that when the condition is met ≤ If a condition is met, the function returns 1; otherwise, it returns 0. Let be the elevation (in meters) of the center point of the i-th grid cell. The above model guarantees that at the current water level... Below, statistics show that the elevation of all center points is lower than [the specified value]. The reservoir capacity at the corresponding water level is obtained by summing the volumes of the grid cells. To meet ≤ The required total number of mesh cells.

[0032] The final water level-reservoir capacity and water level-inundated area relationship curves, along with corresponding numerical data tables, are output. These results can be directly applied to subsequent analysis, judgment, and decision support work, such as hydrological situation analysis, inundation risk assessment, breach flood prediction, and personnel evacuation plan formulation, in response to landslide dammed lake emergencies.

[0033] The specific embodiments of the present invention are further described below: Example 1 This embodiment focuses on a high-mountain canyon-type barrier lake triggered by an earthquake. A 1:5000 scale regional topographic map is used to construct the relationship between reservoir capacity, inundated area, and water level. The specific implementation steps are as follows: Data preparation and preprocessing: Collect 1:5000 topographic maps of the landslide dammed lake area, and use GIS software to digitally extract the river centerline. L The left and right boundary lines of the river channel and Topographic lines on the left and right banks of the river and A vector database was created; the elevation of the top of the landslide dam was obtained through on-site measurements. =1250m, elevation of the riverbed at the landslide dam =1180m.

[0034] Constructing a constrained DEM: Using a vector database as constraints, and employing GIS software or a custom program, the TIN algorithm of the GIS software is used for elevation interpolation to generate a digital elevation model of the upstream river channel area of ​​the landslide dammed lake. (x,y).

[0035] Generating the largest lake model: 3D modeling can be performed using ArcGIS software. In the 3D modeling environment, define the weir crest elevation plane S: z=1250m. Perform a 3D Boolean intersection operation between the DEM model and the space below plane S to generate the largest possible lake model. ArcGIS has a built-in visualization function for 3D Boolean intersection, and the details of 3D Boolean intersection operations will not be elaborated here.

[0036] 3D mesh discretization: Since the topographic map scale is 1:5000, the mesh parameters are set according to standard: Δx=Δy=1.0m, Δz=1m; the lake model is then discretized. Divide the grid into N regular meshes and calculate the projected area of ​​each mesh. ,volume and center point coordinates ( , , ).

[0037] The relationship curve calculation includes calculating the water level-inundated area relationship and the water level-reservoir capacity relationship: Calculate the water level-inundated area relationship: Set the water level calculation range [1180m, 1250m], step size H =1m; for each water level , with step size H Traverse all grid cells and calculate the elevation of their center points. ≤ And the total number of mesh cells with the smallest difference Calculate the corresponding inundation area according to formula (3). After traversing all points, a series of points relating water level to submerged area are generated, which are then connected to form a curve. Regarding the water level-reservoir capacity curve: based on the same water level range and step size, traverse each water level... Calculate the elevation of all center points ≤ Total number of grid cells Calculate the corresponding storage capacity according to formula (4) Once the traversal is complete, a series of points representing the water level-reservoir capacity relationship will be generated, which can then be connected to form a curve.

[0038] Results and Applications: Outputs the final water level-reservoir capacity and water level-inundated area relationship curves and data tables, which can be directly applied to subsequent analysis, judgment and decision support for the emergency response to landslide dammed lakes.

[0039] By following the above steps, the method for rapidly constructing the relationship between reservoir capacity, inundation area, and water level of a landslide dammed lake, as proposed in this invention, can be implemented.

[0040] Example 2 This embodiment focuses on a low-mountain landslide dammed lake caused by a rainstorm. A 1:20,000 scale regional topographic map is used to construct the relationship between reservoir capacity, inundated area, and water level. The core difference is that the grid parameters are set to Δx=Δy=2.0m and Δz=1m. The remaining steps are the same as in Embodiment 1. Finally, a reliable reservoir capacity-inundated area-water level relationship curve is quickly generated, providing key data support for the emergency response of the landslide dammed lake.

[0041] The above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for rapidly constructing the relationship between reservoir capacity, inundated area, and water level of a landslide-dammed lake, characterized in that, Includes the following steps: 1) Constructing a Digital Elevation Model (DEM) of the landslide dammed lake area: Collecting topographic maps of the landslide dammed lake area to generate a digital elevation model of the upstream river channel area of ​​the landslide dammed lake. (x,y), where (x,y) are planar coordinates; 2) Based on the digital elevation model obtained in step 1) (x,y) Constructing the largest lake model of the landslide dammed lake: In the 3D modeling environment, define a plane model S of the dam crest elevation, where the plane model S is expressed as z= Where z is the elevation coordinate in three-dimensional space; the digital elevation model The intersection of (x,y) with the space below the dam crest elevation plane S is used to generate the largest lake model of the landslide dammed lake. ; 3) The largest lake model obtained in step 2) Discretize the 3D mesh: This involves creating a maximum lake model. Divide the grid into N meshes and calculate the projected area of ​​each mesh. ,volume and center point coordinates ( , , ); 4) Based on the grid parameters obtained in step 3), construct a water level-inundation area calculation model and generate a relationship curve: set the water level calculation range as [ , ],in The elevation of the riverbed at the location of the landslide dam. The elevation of the top of the landslide dam. = Set water level step H , with step size H Traverse any water level within the water level calculation range The statistics satisfy the center point elevation. ≤ and( - The value is the total number of mesh cells with the minimum difference. Calculate the current water level The submerged area A( After traversing all water levels, a series of points relating the water level to the submerged area of ​​the landslide dam lake are generated, and these points are connected to form a curve. 5) Based on the grid parameters obtained in step 3) and the water level parameters set in step 4), construct a water level-reservoir capacity calculation model and generate a relationship curve: using the water level calculation range set in step 4) [ , and water level step H Traverse any water level The statistics satisfy the center point elevation. ≤ Total number of grid cells Calculate the current water level Under storage capacity V( After traversing all water levels, a series of points representing the water level-reservoir capacity relationship of the landslide dam lake are generated, and these points are connected to form a curve. Output the water level-inundated area relationship curve obtained in step 4) and the water level-reservoir capacity relationship curve obtained in step 5).

2. The method for rapidly constructing the relationship between reservoir capacity, inundated area, and water level of a landslide dammed lake according to claim 1, characterized in that: The construction of the digital elevation model (DEM) of the landslide dammed lake area includes collecting topographic maps of the area and confirming their scale, extracting the river centerline, left and right boundary lines of the river channel, and topographic lines of the left and right banks from the topographic maps to form a vector database, and simultaneously obtaining the elevation of the top of the landslide dam. and the riverbed elevation at the landslide dam ; Using a vector database as terrain constraints, a digital elevation model of the upstream river channel area of ​​the landslide dammed lake was generated by performing elevation interpolation using GIS software and the TIN irregular triangular network algorithm. (x,y).

3. The method for rapidly constructing the relationship between reservoir capacity, inundated area, and water level of a landslide dammed lake according to claim 1, characterized in that: For the largest lake model The 3D mesh discretization process involves determining the mesh generation accuracy according to a set topographic map scale. Specifically, when the topographic map scale is greater than or equal to 1:5000, the mesh planar dimensions Δx = Δy = 0.5m; when the scale is greater than 1:10000 but less than 1:5000, the mesh planar dimensions Δx = Δy = 1.0m; and when the scale is less than or equal to 1:10000, the mesh planar dimensions Δx = Δy = 2.0m. All meshes have the same vertical height Δz. Based on the determined Δx, Δy, and Δz, the largest lake model is then... Cut into N meshes, mesh The geometric parameter characteristics are shown in equation (2): Equation (2) In the formula: For mesh Projected area; For mesh volume; For mesh center point , , Center point The coordinate values.

4. The method for rapidly constructing the relationship between reservoir capacity, inundated area, and water level of a landslide dammed lake according to claim 1, characterized in that: The grid cell with the minimum difference is the grid cell located at the top boundary of the flooded area.

5. The method for rapidly constructing the relationship between reservoir capacity, inundated area, and water level of a landslide dammed lake according to claim 1, characterized in that: The current water level The submerged area The calculation is shown in equation (3): Equation (3) In the formula: For the current calculated water level The submerged area of ​​the lower landslide dammed lake; Current water level The center point elevation is satisfied ≤ And the total number of mesh cells with the smallest difference; Let i be the planar projected area of ​​the i-th qualified mesh body; This is a function that outputs 1 if the condition within the parentheses is met, and 0 otherwise. Let the elevation be the center point elevation of the i-th grid cell; For a given water level value calculated through iteration, and ∈[ , N represents the total number of mesh cells after discretization of the three-dimensional mesh of the maximum lake model.

6. The method for rapidly constructing the relationship between reservoir capacity, inundated area, and water level of a landslide dammed lake according to claim 1, characterized in that: The current water level Under storage capacity The calculation is shown in equation (4): Equation (4) In the formula: For the current calculated water level The reservoir capacity of the landslide-dammed lake; Current water level The following satisfies ≤ The total number of grid cells; For the first Volume of a conditional mesh volume; function Indicates when the condition is met ≤ If a condition is met, the function returns 1; otherwise, it returns 0. is the elevation of the center point of the i-th grid cell; N is the total number of grid cells after discretization of the 3D grid of the maximum lake model.

7. A computer device, characterized in that, It includes at least one processor and a memory communicatively connected to the at least one processor; the memory stores instructions executable by the at least one processor, which, when executed by the at least one processor, enable the at least one processor to perform the rapid construction method for the relationship between reservoir capacity, inundation area, and water level of a landslide dammed lake as described in any one of claims 1-6.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the method for rapidly constructing the relationship between reservoir capacity, inundation area, and water level of a landslide dammed lake as described in any one of claims 1-6.

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