A dynamic simulation system for the evolution of reservoir dam-break floods based on topographic factors

Abstract

This invention discloses a dynamic simulation system for the evolution of reservoir dam-break floods based on topographic factors, comprising: a basic database of dam-break floods, a calculator for important indicators, a flood passage water level calculation model, a disaster area inversion model, and a time series visualization tool. This invention fully utilizes topographic information from digital elevation models, and calculates important indicators based on readily available conventional parameters such as the dam body and perennial water level; it establishes a flood passage water level calculation model to obtain regional inundation water levels, segments the topographic data by inundation water level elevation to obtain flood-inundated areas, and performs rapid statistical analysis based on data of houses and other land features; it creates a timeline to simulate and present information such as flood water levels, inundation range, and inundation paths according to the timeline, realizing dynamic simulation of dam-break floods and forming a dynamic evolution simulation and display tool for flood-inundated areas.

Description

Technical Field

[0001] This invention belongs to the field of dam-break flood simulation technology, and in particular relates to a dynamic simulation system for the evolution of reservoir dam-break floods based on topographic factors. Background Technology

[0002] In recent years, against the backdrop of global climate change, extreme rainstorms and floods have become more frequent, impacting dam stability and significantly increasing the probability of dam failures. Therefore, risk management of reservoir areas and effective dam failure prevention and mitigation measures are necessary. Technologies for dynamic simulation and visualization of dam failure floods are of great significance for reservoir area risk management and disaster prevention and mitigation efforts.

[0003] Existing technologies for simulating dam-break floods have the following problems: 1. Topographic information plays a very important role in the disaster assessment of downstream areas of dam-break floods, but the participation of topographic information in existing technologies is insufficient; 2. Flood analysis requires long-term observation data, which is difficult and time-consuming to collect, and the early research on dam site selection cannot meet the requirements of speed and fewer parameters; 3. Buildings are the carriers of human production and life, and current research has few time-segmented simulation methods for floods and damaged buildings, and lacks tools for simulating and displaying the dynamic evolution of flood-inundated areas. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a dynamic simulation system for the evolution of reservoir dam-break floods based on topographic factors.

[0005] The present invention is achieved through the following technical solutions.

[0006] This invention provides a dynamic simulation system for the evolution of reservoir dam-break floods based on topographic factors, comprising: a basic database of dam-break floods, a calculator for important indicators, a flood passage water level calculation model, a disaster-affected area inversion model, and a time series visualization tool;

[0007] The dam-break flood basic database is used to store basic data on dam-break floods. The basic data on dam-break floods includes: a set of basic information elements of the dam body, a set of hydrological information elements of the watershed where the dam body is located, a set of digital elevation model elements of the watershed where the dam body is located, a set of two-dimensional and three-dimensional data elements of buildings and structures in the watershed where the dam body is located, and a set of basic data elements of transportation land use in the watershed where the dam body is located.

[0008] The important indicator calculator is used to calculate important indicators based on basic data of dam-break floods. The important indicators include: flood volume, maximum instantaneous total flow at the dam site during complete dam failure, total duration of flood discharge, and flood volume downstream of the dam.

[0009] The flood passage water level calculation model is used to simulate the flood water body path and flood water level surface by using basic data and important indicators of dam-break floods.

[0010] The disaster-affected area inversion model is used to obtain statistical results of the disaster-affected area based on the flood level surface. The statistical results of the disaster-affected area include: information on damaged houses and other damaged land features.

[0011] The time series visualization tool is used to construct a time series table, and generate a visualized temporal map and dynamic visualization video based on the time series table, basic data of dam break floods, flood water body paths, flood water level surfaces and statistical results of disaster-stricken areas.

[0012] The visualized temporal map is used to enable click-and-interact queries for different time periods, and the dynamic visualized video is used to visualize the flood water path, flood water level surface, and statistical results of the disaster-stricken area.

[0013] Preferably, the set of basic information elements of the dam body includes: spatial location of the dam body, spatial data elements of the dam body, total reservoir capacity and total water volume at the time of dam failure, water volume below the water level before reservoir impoundment, time after the dam failure flood, dam length, dam crest elevation, dam bottom elevation, normal water level, design flood level, and check flood level;

[0014] The set of hydrological information elements of the basin where the dam is located includes: spatial data of upstream and downstream rivers, the average water level of the upstream reservoir before impoundment, the water depth in front of the dam, the water level at the time of dam failure, the average water level of the area before the dam construction, the average water level of the downstream area of ​​the dam, and the water flow velocity of upstream and downstream of the dam during flood season.

[0015] The set of elements in the digital elevation model of the watershed where the dam is located includes: the watershed base digital elevation model and digital elevation model data;

[0016] The set of two-dimensional and three-dimensional data elements of buildings and structures in the basin where the dam is located includes: two-dimensional building data and three-dimensional building white model data within the basin.

[0017] Preferably, the expression for calculating the volume of the floodwater is:

[0018] W flood =W dam_breaking -W before_dam_building

[0019] In the formula: W flood For the volume of floodwater, W dam_breaking The total reservoir capacity and total water volume at the time of the collapse, W before_dam_building This refers to the volume of water below the water level before the reservoir is impounded.

[0020] Preferably, the calculation expression for the maximum instantaneous total failure flow at the dam site is:

[0021] H = H dam_breaking -H before_dam_building

[0022]

[0023] In the formula: Q m Let B be the maximum instantaneous total failure flow rate at the dam site, B be the dam length, H be the water depth in front of the dam, g be the gravity coefficient, and H be the maximum instantaneous total failure flow rate at the dam site. dam_breaking The high water level at the time of the dam breach, H before_dambuilding This refers to the average annual water level in the area before the dam was built.

[0024] Preferably, the calculation expression for the total duration of floodwater discharge is as follows:

[0025]

[0026] In the formula: T is the total duration of floodwater discharge, W flood For the volume of floodwater, Q m The maximum instantaneous flow rate at the dam site during total collapse;

[0027] The formula for calculating the downstream flood volume of the dam is as follows:

[0028]

[0029] In the formula: W downstream_flood t is the downstream flood volume, t is the time after the dam break flood, T is the total duration of floodwater discharge, and Q is the total volume of water discharged downstream of the dam. m The maximum instantaneous flow rate at which the dam site collapses completely.

[0030] Preferably, the step of obtaining the flood water path and flood level surface through simulation of basic data and key indicators of dam-break floods includes the following steps:

[0031] Set the fitting granularity parameter and obtain the time period;

[0032] Generate flood water path based on basic data of dam-break floods;

[0033] Calculate the downstream flood volume of the dam body for each time period based on key indicators;

[0034] Calculate the bottom surface of the floodwater body based on basic data of dam-break floods;

[0035] Calculate the flood level for each time period based on the flood path, the downstream flood volume of the dam at each time period, and the bottom surface of the flood body.

[0036] The flood water level points at different times are collected to form a flood water level curve, and the flood water level surface is formed by translating the flood water level curve.

[0037] Preferably, the calculation of the bottom surface of the floodwater body based on the basic data of the dam-break flood includes the following steps:

[0038] Calculate the path length of the floodwaters;

[0039] Extract river water levels based on basic data of dam-break floods;

[0040] The river water level is intercepted based on the length of the flood water body path to obtain the bottom surface of the flood water body.

[0041] Preferably, the calculation of the flood level for each time period based on the flood path, the downstream flood volume of the dam at each time period, and the bottom surface of the flood water body includes the following steps:

[0042] Obtain the perpendicular lines at both ends of the flood path by examining the flood water body path and the bottom surface of the flood water body;

[0043] The digital elevation model data is cropped based on the perpendicular lines at both ends of the path to obtain the digital elevation model data within the flood-affected area.

[0044] Set up flood level variables within the region, and calculate the cut and fill volume based on the digital elevation model data of the flood-affected area and the flood level variables within the region.

[0045] The flood level for each period is calculated based on the volume of excavation and filling and the downstream flood volume of the dam at each time period.

[0046] Preferably, obtaining the statistical results of the disaster-stricken area based on the flood level surface includes the following steps:

[0047] A digital elevation model of the flood surface is generated based on the flood level surface.

[0048] The extent of the disaster-affected area is obtained from the flood surface digital elevation model;

[0049] Information on damaged houses and other damaged features was obtained by overlay analysis and statistical analysis based on basic data of dam break floods and the extent of the affected area.

[0050] Classify and statistically analyze information on damaged houses and other damaged features, and output the statistical results of the affected areas in a formatted manner.

[0051] Preferably, the construction of the time series table, and the generation of a visualized temporal map and a dynamic visualized video based on the time series table, basic data of dam-break floods, flood water body paths, flood water level surfaces, and statistical results of the affected areas, includes the following steps:

[0052] Construct a time series table, and then construct a time axis based on the time series table;

[0053] The flood water body path is segmented to obtain the segmented flood water body path, and the temporal attributes of the segmented flood water body path are constructed to form a flood path temporal data set;

[0054] The flood level surface is segmented to obtain block flood level surfaces. Temporal attributes are constructed on the block flood level surfaces to form a flood level temporal data set.

[0055] A temporal data set of affected buildings and features was obtained based on the flood level surface and statistical results of the affected area.

[0056] Based on the time series table, the temporal data set of flood path, the temporal data set of flood level, and the temporal data set of disaster-affected buildings and features, a visual temporal map and a dynamic visual video are generated.

[0057] The beneficial effects of this invention are as follows:

[0058] 1. Make full use of the topographic information of the digital elevation model, and based on easily obtainable conventional parameters such as the dam body and the perennial water level, use water level and topographic information to calculate the reservoir capacity before the dam failure event, and calculate important index quantities and other result data.

[0059] 2. Establish a flood passage water level calculation model. The model selects the terrain range based on the total outflow of water from the dam and the passing terrain area. Within the terrain range, an iterative algorithm is used to continuously simulate the fit between the water level rise and the total water volume to obtain the regional inundation water level. The terrain data is segmented by the inundation water level elevation to obtain the flood inundation area, and rapid statistics are performed based on the data of houses and other land features.

[0060] 3. Create a timeline to simulate and present information such as flood level, inundation range, and inundation path according to the timeline, realize dynamic simulation of dam-break floods, and form a dynamic evolution simulation display tool for flood-inundated areas. Attached Figure Description

[0061] Figure 1 This is a schematic diagram of the system structure provided in an embodiment of the present invention;

[0062] Figure 2 This is a schematic diagram of the system data flow provided in an embodiment of the present invention. Detailed Implementation

[0063] The technical solution of the present invention is further described below, but the scope of protection is not limited to what is described.

[0064] like Figure 1 As shown, a dynamic simulation system for the evolution of reservoir dam-break floods based on topographic factors includes: a basic database of dam-break floods, a calculator for important indicators, a flood passage water level calculation model, a disaster-affected area inversion model, and a time series visualization tool.

[0065] The dam-break flood basic database is used to store basic data on dam-break floods. The basic data on dam-break floods includes: a set of basic information elements of the dam body, a set of hydrological information elements of the watershed where the dam body is located, a set of digital elevation model elements of the watershed where the dam body is located, a set of two-dimensional and three-dimensional data elements of buildings and structures in the watershed where the dam body is located, and a set of basic data elements of transportation land use in the watershed where the dam body is located.

[0066] By establishing a dam-break flood baseline database, various data indicators and data storage methods are clearly defined by category. A standardized data storage model and space are constructed, and data formats and spatial data geographic coordinate systems are normalized. This enhances the applicability of the methodology and provides a standardized data resource foundation for rapid response. The dam-break flood baseline database uses a unified Geodatabase format for storage and employs Datasets for categorized management. Specific data information is stored in FeatureClasses for each feature.

[0067] The set of basic information elements of the dam body includes: spatial location of the dam body, spatial data elements of the dam body, total reservoir capacity and total water volume at the time of the dam failure, water volume below the water level before reservoir impoundment, time after the dam failure flood, dam length, dam crest elevation, dam bottom elevation, normal water level, design flood level, and check flood level;

[0068] The set of hydrological information elements of the basin where the dam is located includes: spatial data of upstream and downstream rivers, the average water level of the upstream reservoir before impoundment, the water depth in front of the dam, the water level at the time of dam failure, the average water level of the area before the dam construction, the average water level of the downstream area of ​​the dam, and the water flow velocity of upstream and downstream of the dam during flood season.

[0069] The set of elements in the digital elevation model of the watershed where the dam is located includes: the watershed base digital elevation model and digital elevation model data;

[0070] Digital elevation model data includes various raster elevation model data used in the calculation process.

[0071] The set of two-dimensional and three-dimensional data elements of buildings and structures in the basin where the dam is located includes: two-dimensional building data and three-dimensional building white model data within the basin.

[0072] The data includes attribute data for two-dimensional buildings within the watershed, and attribute data for three-dimensional building white models.

[0073] The important indicator calculator is used to calculate important indicators based on basic data of dam-break floods. The important indicators include: flood volume, maximum instantaneous total flow at the dam site during complete dam failure, total duration of flood discharge, and flood volume downstream of the dam.

[0074] Following a dam failure, the greatest harm manifests as the outflow of water, creating a flood peak downstream that erodes downstream areas, inundates residential and industrial areas, and triggers secondary geological disasters such as landslides and mudslides. The flood volume is the volume of water formed by the total reservoir capacity at the time of dam failure and the reservoir's initial water level. The expression for calculating the flood volume is:

[0075] W flood =W dam_breaking -W before_dam_building

[0076] In the formula: W flood For the volume of floodwater, W dam_breaking The total reservoir capacity and total water volume at the time of the collapse, W before_dam_building This refers to the volume of water below the water level before the reservoir is impounded.

[0077] The unit for the volume of floodwater is m. 3 The unit for the total reservoir capacity at the time of collapse is m³. 3 The unit for the volume of water below the reservoir's water level before impoundment is m. 3 .

[0078] In this embodiment, in order to automate and streamline the calculation of flood water volume indicators, the calculation process is encapsulated in a streamlined and tool-based manner based on the Python development environment and the arcpy site package. Based on digital elevation model data, with the water level before reservoir impoundment as the baseline data and the water level at the time of dam failure as the target water level, the base digital elevation model data is modified using water level elevation and water level surface information to form digital elevation data at two different time points: before reservoir impoundment and at the time of dam failure. The flood water volume is then calculated using excavation and filling tools.

[0079] Regarding dam failure modes, considering the dam's layout and the construction characteristics of roller-compacted concrete dams, two possible failure modes are considered: instantaneous total failure and instantaneous partial failure. This invention considers the most unfavorable scenario of damage and the most adverse impact on downstream areas, adopting the instantaneous total failure mode. The dam site flow rate determines the water volume changes during the formation and evolution of the dam-break flood. Following the principle of "most unfavorable and most dangerous," the empirical formula from the Ministry of Railways is used to calculate the dam site flow rate. The expression for calculating the maximum instantaneous total failure flow rate at the dam site is:

[0080] H = H dam_breaking -H before_dam_building

[0081]

[0082] In the formula: Q m Let B be the maximum instantaneous total failure flow rate at the dam site, B be the dam length, H be the water depth in front of the dam, g be the gravity coefficient, and H be the maximum instantaneous total failure flow rate at the dam site. dam_breaking The high water level at the time of the dam breach, Hbefore_dambuilding It is the perennial water level in this area before the dam construction.

[0083] Among them, the unit of the maximum instantaneous full-break flow at the dam site is m 3 / s, the unit of the dam body length is m, the unit of the water depth in front of the dam is m, the unit of the water level height at the time of dam break is m, and the unit of the perennial water level in this area before the dam construction is m. It usually takes a value of 5, and g takes a value of 9.8 N / kg.

[0084] The total flood water discharge duration is a representation of the discharge of the flood water volume. The calculation expression of the total flood water discharge duration is:

[0085]

[0086] In the formula: T is the total flood water discharge duration, W flood is the flood water volume, Q m is the maximum instantaneous full-break flow at the dam site;

[0087] Among them, the unit of the total flood water discharge duration is s, the unit of the flood water volume is m 3 3, and the unit of the maximum instantaneous full-break flow at the dam site is m 3 / s.

[0088] After the dam break event occurs, the flood flows out through the dam site. The total time is T. For the time t after the dam break, when t < T, there is a positive correlation between the flood volume downstream of the dam body and it. When t ≥ T, all the flood water is discharged downstream of the dam body for accounting, and the flood volume downstream of the dam body is stable. The calculation expression of the flood volume downstream of the dam body is:

[0089]

[0090] In the formula: W downstream_flood is the flood volume downstream of the dam body, t is the time after the dam break flood occurs, T is the total flood water discharge duration, Q m is the maximum instantaneous full-break flow at the dam site.

[0091] Among them, the unit of the flood volume downstream of the dam body is m 3 3, the unit of the time after the dam break flood occurs is s, the unit of the total flood water discharge duration is s, and the unit of the maximum instantaneous full-break flow at the dam site is m 3 / s.

[0092] The flood passing water level resolution model is used to simulate through the basic data and important index quantities of the dam break flood to obtain the flood water path and the flood water level surface;

[0093] When a flood passes through a region, there is a maximum flood level. At this time, a flood passage range will be formed on both sides of the river, and all affected areas will be affected by the flood. Considering the two-dimensional shape of the river valley and the water level elevation of the flood, from the overall time series perspective, the flood passage water level line is a three-dimensional curve. In order to realize the spatial calculation of this three-dimensional curve, a topographic-based passage water level calculation model was constructed.

[0094] The process of simulating flood water path and flood level surface using basic data and key indicators of dam-break floods includes the following steps:

[0095] Set the fitting granularity parameter and obtain the time period;

[0096] The flood level at the elevation level is the total time t between the flood level and the dam breach. totall In the overall fitting process of a two-dimensional function, the setting of the time span affects the granularity of the curve solution. Therefore, setting the time span t... block As a variable parameter of granularity in the solution process.

[0097] Generate flood water path based on basic data of dam-break floods;

[0098] Retrieve downstream river centerline data and downstream water flow velocity (v) during flood season from the dam breach flood database, according to a pre-defined time span (t). block Obtain the length L of each fitted interval block Using the arcpy linear feature piecewise function, with L block To segment the downstream river centerline, the flood water path L is obtained by segmenting the distance. downstream_flood If the total time t after the dam collapse occurs totall With time span t block If the ratio is N, then L downstream_flood =N*L block .

[0099] Calculate the downstream flood volume of the dam body for each time period based on key indicators;

[0100] By calling the key indicator calculator for the dam-break flood history, the time t after the dam break is calculated. totall According to the time span t block After being segmented and summarized at each level, the data is used as input parameters. Other relevant computational quantities are then called from the dam-break flood basic database to participate in the calculation, thereby obtaining the downstream flood volume index of the dam body for each time period.

[0101] Calculate the bottom surface of the floodwater body based on basic data of dam-break floods;

[0102] The calculation of the bottom surface of the floodwater body based on the basic data of the dam break flood includes the following steps:

[0103] Calculate the path length of the floodwaters;

[0104] Due to the influence of the river valley topography, the flood inundation area is an irregular two-dimensional surface. The determination of the bottom of the flood body needs to be based on the length of the flood path and the average annual water level, specifically the time t after the dam-break flood occurs. totall The functional relationship between the floodwater velocity (v) in the downstream watershed where the dam is located and the floodwater path is determined using time and velocity, is illustrated by the following formula for calculating the flood path length:

[0105]

[0106] Extract river water levels based on basic data of dam-break floods;

[0107] By the downstream perennial water level height H perennial_water_level The river water level was extracted using digital elevation model data and calculated based on the time t after the dam-break flood. totall .

[0108] The river water level is intercepted based on the length of the flood water body path to obtain the bottom surface of the flood water body.

[0109] The generated river water level is intercepted based on the flood water body path length to obtain the flood water body bottom surface S. flood_underside .

[0110] Calculate the flood level for each time period based on the flood path, the downstream flood volume of the dam at each time period, and the bottom surface of the flood body.

[0111] The calculation of flood water level for each time period based on the flood path, downstream flood volume of the dam at each time period, and bottom surface of the flood water body includes the following steps:

[0112] Obtain the perpendicular lines at both ends of the flood path by examining the flood water body path and the bottom surface of the flood water body;

[0113] Using the length of the flood water body L flood Floodwater bottom surface S flood_underside Obtain the perpendicular lines at both ends of the path and extend and expand them.

[0114] The digital elevation model data is cropped based on the perpendicular lines at both ends of the path to obtain the digital elevation model data within the flood-affected area.

[0115] The digital elevation model (DEM) data is cropped to obtain the DEM data for the flood-affected area. zonal .

[0116] Set up flood level variables within the region, and calculate the cut and fill volume based on the digital elevation model data of the flood-affected area and the flood level variables within the region.

[0117] Set the flood level variable h within the area flood_level By using excavation and filling tools, the volume of fill under different water levels is calculated, and the difference between the fill volume and the flood volume is obtained.

[0118] The flood level for each period is calculated based on the volume of excavation and filling and the downstream flood volume of the dam at each time period.

[0119] Adjusting flood level variable h using variable step size flood_level The downstream flood volume W of the dam is detected by detecting abrupt changes in positive and negative values. downstream_flood Calculated volume W of excavation and filling cut_fill The flood level variable whose difference approaches zero is used as the flood level calculation result for the current time period. The expression is:

[0120] W Δ =F cut_fill (DEM zonal (t),h flood_level H perennial_water_level )-W downstream_flood (t)

[0121] In the formula: t is the time after the dam-break flood, in seconds (s) and hours (W). downstream_flood Let t be the downstream flood volume of the dam, in m³. 3 DEM zonal (t) represents the digital elevation model data of the flood-affected area at time t, F cut_fill H is the function for calculating the volume of cut and fill. perennial_water_level The average annual water level downstream, h flood_level Let W be the flood level variable at the current location at time t. Δ This is the volume difference.

[0122] The flood water level points at different times are collected to form a flood water level curve, and the flood water level surface is formed by translating the flood water level curve.

[0123] Extract the center points of the flood water body path at each time interval, record the corresponding flood water level calculation results, combine them to form a flood curve point set, and string them together to form a flood water level curve. Using the flood water level curve, form a flood water level surface by translating the surface.

[0124] The disaster-affected area inversion model is used to obtain statistical results of the disaster-affected area based on the flood level surface. The statistical results of the disaster-affected area include: information on damaged houses and other damaged land features.

[0125] The process of obtaining statistical results of the disaster-stricken area based on the flood level surface includes the following steps:

[0126] A digital elevation model of the flood surface is generated based on the flood level surface.

[0127] In this embodiment, based on the flood level curve, statistical tools are constructed using the Python development environment and the arcpy site package. The FeatureToRaster function is used to convert the surface into raster data, forming a digital elevation model of the flood surface.

[0128] The extent of the disaster-affected area is obtained from the flood surface digital elevation model;

[0129] By combining the downstream digital elevation model with the flood surface digital elevation model, the Reclassify function is used to set a value of 1 when the flood surface elevation value is greater than the downstream digital elevation model value, and a value of empty when the flood surface elevation value is less than the downstream elevation value. The RasterToPolygon function is used to convert the generated raster data into vector data to obtain the disaster area extent. The above method for obtaining the disaster area extent solves the problem of the tortuous river edge, obtains the river edge more realistically, and incorporates the surface feature information of the flood surface.

[0130] Information on damaged houses and other damaged features was obtained by overlay analysis and statistical analysis based on basic data of dam break floods and the extent of the affected area.

[0131] Data was extracted from a dam-break flood baseline database to obtain data on buildings and structures in the dam's basin. The dataset of basic data elements in the basin included river data, highway data, railway data, transportation hubs, transportation facilities, and land use types. Using the Intersect function, information on affected buildings and other affected features was obtained through overlay and statistical analysis.

[0132] Classify and statistically analyze information on damaged houses and other damaged features, and output the statistical results of the affected areas in a formatted manner.

[0133] The time series visualization tool is used to construct a time series table, and generate a visualized temporal map and dynamic visualization video based on the time series table, basic data of dam break floods, flood water body paths, flood water level surfaces and statistical results of disaster-stricken areas.

[0134] The visualized temporal map is used to enable click-and-interact queries for different time periods, and the dynamic visualized video is used to visualize the flood water path, flood water level surface, and statistical results of the disaster-stricken area.

[0135] GIS-based 3D dam-break flood evolution visualization not only provides decision-makers with a more intuitive understanding, but also offers a rapid, accurate, and intuitive means of analyzing the time, location, scope, and intensity of flood events. It can accurately simulate the inundation range and water depth distribution of floods, providing fast and efficient information support for making scientific flood control and disaster reduction decisions. A time series visualization tool has been developed.

[0136] The process of constructing a time series table and generating a visualized temporal map and dynamic visualization video based on the time series table, basic data on dam-break floods, flood water body paths, flood water level surfaces, and statistical results of the affected areas includes the following steps:

[0137] Construct a time series table, and then construct a time axis based on the time series table;

[0138] The flood water body path is segmented to obtain the segmented flood water body path, and the temporal attributes of the segmented flood water body path are constructed to form a flood path temporal data set;

[0139] Using L in different time periods block The data is divided into time segments t and t after the dam-break flood. block Temporal attributes are constructed from the segmented flood surface data to form a flood path temporal data set.

[0140] The flood level surface is segmented to obtain block flood level surfaces. Temporal attributes are constructed on the block flood level surfaces to form a flood level temporal data set.

[0141] According to L in each time period block The data is segmented to obtain block-based flood surface data, and the data is divided into segments based on the time t after the dam-break flood. block Temporal attributes are constructed from the segmented flood surface data to form a set of temporal flood level data.

[0142] A temporal data set of affected buildings and features was obtained based on the flood level surface and statistical results of the affected area.

[0143] Simultaneously, based on the flood level at each time period, the intersection of surrounding buildings and other land features is performed, and the corresponding time values ​​are assigned to the buildings and other land features to complete the temporal data set of the disaster-affected buildings and land features.

[0144] Based on the time series table, the temporal data set of flood path, the temporal data set of flood level, and the temporal data set of disaster-affected buildings and features, a visual temporal map and a dynamic visual video are generated.

[0145] A timeline was constructed for the overall flood process, and a time slider was used to create a visualized temporal map. Click-and-interact queries were enabled for each time period. The flood process and the affected areas were simulated in a linked manner. At the same time, a time series table was constructed based on the time attributes of the elements contained in various temporal data sets. Based on the time series table, a dynamic visualization video of the entire process of the dam-break flood was generated. The functions were encapsulated to complete the creation of a time series visualization tool.

[0146] This invention fully utilizes the topographic information of digital elevation models. Based on readily available conventional parameters such as dam body and perennial water level, it calculates the reservoir capacity before a dam break event using water level and topographic information, and obtains important index data. A flood passage water level calculation model is established. The model selects the topographic range based on the total outflow from the dam outlet and the passing topographic area. Within the topographic range, an iterative algorithm continuously simulates the consistency between water level rise and total water volume to obtain the regional inundation water level. The topographic data is segmented by the inundation water level elevation to obtain the flood inundation area, and rapid statistics are performed based on data of houses and other land features. A timeline is created to simulate and present information such as flood water level, inundation range, and inundation path according to the timeline, realizing dynamic simulation of dam break floods and forming a dynamic evolution simulation and display tool for flood inundation areas.

Claims

1. A dynamic simulation system for the evolution of reservoir dam-break floods based on topographic factors, characterized in that, include: Basic database of dam-break floods, calculator for key indicators, flood passage water level calculation model, disaster-affected area inversion model, and time series visualization tool; The dam-break flood basic database is used to store basic data on dam-break floods. The basic data on dam-break floods includes: a set of basic information elements of the dam body, a set of hydrological information elements of the watershed where the dam body is located, a set of digital elevation model elements of the watershed where the dam body is located, a set of two-dimensional and three-dimensional data elements of buildings and structures in the watershed where the dam body is located, and a set of basic data elements of transportation land use in the watershed where the dam body is located. The important indicator calculator is used to calculate important indicators based on basic data of dam-break floods. The important indicators include: flood volume, maximum instantaneous total flow at the dam site during complete dam failure, total duration of flood discharge, and flood volume downstream of the dam. The flood passage water level calculation model is used to simulate flood water body paths and flood water level surfaces by using basic data and key indicators of dam-break floods. The model includes the following steps: setting fitting granularity parameters and obtaining time periods; generating flood water body paths based on basic dam-break flood data; calculating downstream flood volumes for each time period based on key indicators; calculating the bottom surface of the flood water body based on basic dam-break flood data; calculating flood water levels for each time period based on the flood water body paths, downstream flood volumes for each time period, and bottom surface of the flood water body; collecting flood water level points for each time period to form a flood water level curve; and forming a flood water level surface by translating the flood water level curve. The disaster-affected area inversion model is used to obtain statistical results of the disaster-affected area based on the flood level surface. The statistical results of the disaster-affected area include: damaged houses and other land features. The time series visualization tool is used to construct a time series table, and generate a visualized temporal map and dynamic visualization video based on the time series table, basic data of dam break floods, flood water body paths, flood water level surfaces and statistical results of disaster-stricken areas. In the process of generating the flood water path using the flood passage water level calculation model, downstream river centerline data and the downstream water flow velocity v during the flood season in the basin where the dam is located are retrieved from the dam-break flood basic database, according to the time span. Obtain the length of each fitted interval Using the arcpy linear feature piecewise function, to To obtain the flood water path, the downstream river centerline is segmented into segments based on the segmented distance. If the total time after the dam collapse With time span The ratio is N, then ; When calculating the bottom surface of a flood body, the length of the flood path is calculated; the river water level is extracted based on the basic data of the dam-break flood; the river water level is then extracted based on the length of the flood path to obtain the bottom surface of the flood body. When calculating the flood level for each time period, the vertical lines at both ends of the flood path and the bottom of the flood body are obtained; the elevation model data is cropped based on the vertical lines at both ends of the path to obtain the digital elevation model data within the flood-affected area; the flood level variable within the area is set, and the cut-and-fill volume is calculated based on the digital elevation model data within the flood-affected area and the flood level variable within the area; the flood level for each time period is calculated based on the cut-and-fill volume and the downstream flood volume of the dam body for each time period.

2. The dynamic simulation system for the evolution of reservoir dam-break floods as described in claim 1, characterized in that, The set of basic information elements of the dam body includes: spatial location of the dam body, spatial data elements of the dam body, total reservoir capacity and total water volume at the time of the dam failure, water volume below the water level before reservoir impoundment, time after the dam failure flood, dam length, dam crest elevation, dam bottom elevation, normal water level, design flood level, and check flood level; The set of hydrological information elements of the basin where the dam is located includes: spatial data of upstream and downstream rivers, the average water level of the upstream reservoir before impoundment, the water depth in front of the dam, the water level at the time of dam failure, the average water level of the area before the dam construction, the average water level of the downstream area of ​​the dam, and the water flow velocity of upstream and downstream of the dam during flood season. The set of elements of the digital elevation model of the watershed where the dam is located includes: the watershed base digital elevation model and elevation model data; The set of two-dimensional and three-dimensional data elements of buildings and structures in the basin where the dam is located includes: two-dimensional building data and three-dimensional building white model data within the basin.

3. The dynamic simulation system for the evolution of reservoir dam-break floods as described in claim 1, characterized in that, The formula for calculating the volume of the floodwater body is: In the formula: For the volume of floodwater, The total reservoir capacity and total water volume at the time of the collapse This refers to the volume of water below the water level before the reservoir is filled.

4. The dynamic simulation system for the evolution of reservoir dam-break floods as described in claim 1, characterized in that, The formula for calculating the maximum instantaneous total failure flow at the dam site is: In the formula: Let B be the maximum instantaneous total failure flow rate at the dam site, B be the dam length, H be the water depth in front of the dam, and g be the gravity coefficient. The dam was breached when the water level was high. This refers to the average annual water level in the area before the dam was built.

5. The dynamic simulation system for the evolution of reservoir dam-break floods as described in claim 1, characterized in that, The formula for calculating the total duration of floodwater discharge is as follows: In the formula: T is the total duration of floodwater discharge, For the volume of floodwater, The maximum instantaneous flow rate at the dam site during total collapse; The formula for calculating the downstream flood volume of the dam is as follows: In the formula: t is the downstream flood volume, t is the time after the dam breach flood, and T is the total duration of floodwater discharge. The maximum instantaneous flow rate at which the dam site collapses completely.

6. The dynamic simulation system for the evolution of reservoir dam-break floods as described in claim 1, characterized in that, The process of obtaining statistical results of the disaster-stricken area based on the flood level surface includes the following steps: A digital elevation model of the flood surface is generated based on the flood level surface. The extent of the disaster-affected area is obtained from the flood surface digital elevation model; Based on the basic data of the dam break flood and the scope of the affected area, the submerged buildings and other land features were obtained through overlay analysis and statistical analysis. The system categorizes and statistically analyzes submerged buildings, houses, and other features, and outputs the disaster area statistics in a formatted manner.

7. The dynamic simulation system for the evolution of reservoir dam-break floods as described in claim 1, characterized in that, The process of constructing a time series table and generating a visualized temporal map and dynamic visualization video based on the time series table, basic data on dam-break floods, flood water body paths, flood water level surfaces, and statistical results of the affected areas includes the following steps: Construct a time series table, and then construct a time axis based on the time series table; The flood water body path is segmented to obtain the segmented flood water body path, and the temporal attributes of the segmented flood water body path are constructed to form a flood path temporal data set; The flood level surface is segmented to obtain block flood level surfaces. Temporal attributes are constructed on the block flood level surfaces to form a flood level temporal data set. A set of temporal data on affected buildings and features was obtained based on the flood level surface and statistical results of the affected area. Based on the time series table, the temporal data set of flood path, the temporal data set of flood level, and the temporal data set of disaster-affected buildings and features, a visual temporal map and a dynamic visual video are generated.

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