Method and system for simulating influence of tailing pond overtopping dam break on downstream

Abstract

The invention relates to the technical field of model tests, in particular to a method and a system for simulating influence of tailing pond overtopping dam break on downstream. The method comprises the following steps: designing a tailing pond overtopping dam break simulation test scheme according to a tailing pond area and surrounding terrain, geology and design data; determining model sand comparison and selection and model scale comparison and selection according to the designed test scheme; establishing a tailing pond dam break physical model according to model sand comparison and selection and model scale comparison and selection; carrying out a tailing pond dam break test based on the tailing pond dam break physical model; and analyzing the dam break deposition amount and the submerging range based on a test result. By means of the technical scheme, the problem that the downstream range is affected by tailing pond overtopping dam break can be solved, and an optimal early warning scheme can be provided.

Description

Technical Field

[0001] The invention relates to the technical field of model tests, and in particular to a method and system for simulating the impact of overtopping and dam-breaking of a tailings pond on downstream areas. Background Art

[0002] A tailings pond is a place for storing ore tailings and is an indispensable industrial building. It has high gravitational potential energy and there is a risk of mudslides in the event of a dam breach.

[0003] As one of the key contents of safety supervision, tailings ponds may cause dam breaches and other accidents under the influence of disturbances such as precipitation and earthquakes. On the basis of strengthening daily safety supervision of tailings ponds and reducing potential accidents, an overtopping dam breach test model is established to study the evolution process, discharge flow and impact distance of dam breach, which is of great significance to strengthening safety management of downstream reservoir areas and reducing the severity of accident consequences.

[0004] Most existing tailings pond simulation tests are conducted using numerical simulation tests. However, numerical simulation tests often require simplification and assumptions of actual problems, ignoring some complex physical phenomena, resulting in a certain deviation between the results and the actual results. Therefore, a physical similarity model test method for tailings ponds is developed to directly display and measure the actual morphological changes and destruction process and data of tailings ponds under various working conditions. Summary of the invention The purpose of the present invention is to provide a method and system for simulating the impact of tailings pond overtopping and dam breach on the downstream, thereby restoring the scenario of tailings pond overtopping and dam breach to a certain extent, determining the scouring and silting patterns of flood water reaching various places downstream under the condition of overtopping and dam breach, determining the water level process lines of different sections, determining the tailings siltation status, and determining the flooding range.

[0005] In the first aspect, the present invention provides a method for simulating the impact of tailings dam overtopping and dam failure on the downstream, which adopts the following technical solution: A method for simulating the impact of tailings dam overtopping and dam failure on downstream, comprising: Design a tailings pond overtopping and dam-break simulation test plan based on the tailings pond area and surrounding terrain, geology and design data; Determine the model sand ratio and model scale ratio according to the designed test plan; Establish the tailings dam break physical model based on the model sand selection and model scale selection; Conduct tailings dam breach test based on tailings dam breach physical model; The dam break sedimentation volume and flooding range are analyzed based on the test results.

[0006] Furthermore, the design of a tailings pond overtopping and dam-burst simulation test plan based on the tailings pond area and surrounding terrain, geology and design data includes collecting the tailings pond area and surrounding terrain, geology and design data, and designing a tailings pond overtopping and dam-burst simulation test plan based on the tailings pond area and surrounding terrain, geology and design data.

[0007] Furthermore, the model sand selection and model scale selection are determined according to the designed test plan, including conducting a water tank test in a glass circulating water tank, adjusting the water flow through the upstream water measuring weir and the downstream tail gate of the water tank to form a quasi-binary uniform flow with a water surface gradient of about one ten-thousandth, determining the model sand selection according to the water tank test, and determining that the starting flow velocity law of the model sand is similar to that of the tailings sand.

[0008] Furthermore, the method of determining the model sand comparison and model scale comparison according to the designed test plan also includes placing a disc with scales on the bottom of the water area in the model large water area, and allowing the model sand to naturally settle and form a mound in still water, with the mound body formed on the disc, determining the height and bottom radius of the mound body, determining the slope of the mound body, and determining that the underwater angle of repose of the model sand is similar to that of the tailings sand.

[0009] Furthermore, the establishment of a tailings dam break physical model based on model sand comparison and model size comparison includes conducting a tailings dam break pre-test based on the tailings dam break physical model to determine the best physical model establishment scheme.

[0010] Furthermore, the tailings dam break pre-test based on the tailings dam break physical model includes testing whether the model sand is suitable for tailings dam break simulation; testing the relationship between the density and plasticity index of the tailings model dam body; and testing the influence of the construction method of the simulated dam break dam body model.

[0011] Furthermore, the tailings dam break test based on the tailings dam break physical model includes determining the maximum flow range of the breach, the maximum flow velocity of the breach, and the amount of tailings accumulation in the downstream channel according to the tailings dam break test model; planning the warning time and escape time of each key point according to the time it takes for the water flow to reach each key point after overflowing the tailings dam model; and drawing a tailings flow trajectory and a schematic diagram of the flooded range after the tailings dam break model overflows and ends.

[0012] Second, a simulation system for the impact of tailings dam overtopping and dam failure on downstream areas, including: The data collection module is configured to design a tailings pond overtopping and dam-break simulation test plan based on the topography, geology and design data of the tailings pond area and surrounding areas; A scheme determination module is configured to determine the model sand ratio and the model scale ratio according to the designed test scheme; The model building module is configured to establish a tailings dam breach physical model based on model sand selection and model scale selection; The test module is configured to perform a tailings dam breach test based on a tailings dam breach physical model; The analysis module is configured to analyze the dam break sedimentation volume and flooding range based on the test results. In a third aspect, the present invention provides a computer-readable storage medium storing a plurality of instructions, wherein the instructions are suitable for being loaded and executed by a processor of a terminal device, a method for simulating the impact of overtopping and dam breach of a tailings dam on the downstream.

[0013] In a fourth aspect, the present invention provides a terminal device comprising a processor and a computer-readable storage medium, the processor being used to implement various instructions; the computer-readable storage medium being used to store a plurality of instructions, the instructions being suitable for being loaded and executed by the processor to simulate the impact of overtopping and dam breach of a tailings dam on the downstream.

[0014] In summary, the present invention has the following beneficial technical effects: 1. Determine the model sand ratio and model size ratio according to the design scheme of the present invention; conduct simulation pre-experiments according to the designed model, and conduct overtopping dam break tests according to the best scheme; 2. Carry out large-scale tailings pond overtopping and dam-break tests, which is a method to intuitively analyze the changing laws of tailings pond dam-break process, flow process, cross-sectional morphology evolution process, infiltration line, submerged elevation and range; 3. Compared with traditional numerical experiments, although numerical experiments have the advantages of high efficiency and convenience, the results may be uncertain due to the limitations of their models and assumptions. Through physical similarity simulation experiments, the numerical model can be verified, the model parameters can be corrected, and the accuracy of numerical simulation can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of a method for simulating the impact of tailings dam overtopping and dam failure on downstream areas in Example 1 of the present invention; Figure 2 It is a schematic diagram of the tailings flow path and flooding range of Example 1 of the present invention. DETAILED DESCRIPTION

[0016] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0017] Example 1 Reference Figure 1 , a method for simulating the impact of tailings dam overtopping and dam failure on downstream in this embodiment, such as Figure 1 As shown, including: Design a tailings pond overtopping and dam-break simulation test plan based on the tailings pond area and surrounding terrain, geology and design data; Determine the model sand ratio and model scale ratio according to the designed test plan; Establish the tailings dam break physical model based on the model sand selection and model scale selection; Conduct tailings dam breach test based on tailings dam breach physical model; The dam break sedimentation volume and flooding range are analyzed based on the test results.

[0018] Specifically, the following steps are included: Step 1: Based on the topography, geology and design data of the tailings pond area and surrounding areas; collect the meteorological, hydrological and topographic conditions of the tailings pond area, and design a tailings pond overtopping and dam-break simulation test plan; Step 2, determining the model sand selection and model scale selection according to the design scheme; wherein, it includes: Calculation of tailings pond model scale, including: Among them, the first formula is: ; in, is the area ratio, is the volume scale, is the horizontal scale; The second formula is: ; in, is the flow rate scale, For time scale; The third formula is: , ; in, is the flow velocity scale, is the vertical scale; The fourth formula is: ; in is the roughness coefficient; in, is the starting flow rate of the bed load single width sand transport rate, D is the sand particle size, is the bulk density of model sand, is the specific gravity of water, is the stable dry volume of the sediment, The sediment is close to the stable dry volume. The value is 0.213×10 -4 cm; The formula of bed load single width sand transport rate improved according to the energy consumption graph: ; in, is the bed load transport rate per unit width, ; is the coefficient related to friction; is the underwater angle of repose of mud and sand; The scale of bed load single width sand transport rate is: According to the riverbed scouring and silting deformation equation caused by bed load movement: ; we can get: in, It is the dry bulk density ratio of bed load sediment. It is the scale of bed load transport rate per unit width. is the specific gravity of mud and sand, It is the scale of the coefficient of bed load transport rate per unit width. It is the time scale of scouring and silting caused by bed load mud and sand; Repeat step 2 to establish the tailings dam breach physical model and conduct a simulation pre-experiment to determine the best physical model establishment scheme.

[0019] As a further embodiment, The target tailings dam in this embodiment is a stacked tailings dam. The average annual precipitation of the target tailings pond from 1961 to 2019 is 1632.5 mm, with the highest value in 2016, reaching 2352.0 mm. The target tailings pond has an elevation of 1138.13 m, a stacking elevation of 452 m, and a total storage capacity of 30.76 million m 3 The total dam height is 175.2 m. According to the Code for Design of Tailing Facilities (GB 50863-2013), it is a Class II reservoir. The catchment area is 1.08 km 2 , covering an area of ​​0.82 km 2 The initial dam top elevation is 413m, the dam axis length is 525m, the dam top width is 25m~115m, the bottom width is more than 600m, and the dam height is 136.2m; The target tailings pond has a catchment area of ​​1.08 km 2 According to the rainstorm flood atlas and rainstorm parameter atlas of the target location, the main calculation parameters used in flood calculation are: Table 1. Flood calculation parameters Table 2. Flood calculation results Table 3. Summary of scales of target tailings dam breach models The test was conducted in a glass circulating water tank, and the water flow was adjusted by the upstream water weir and the downstream tail gate of the water tank, basically forming a quasi-binary uniform flow with a water surface drop of about one ten-thousandth; The comparison of model sand was determined based on flume tests, and it was determined that the starting flow rate patterns of model sand and tailings sand were similar; The sinking velocity test was carried out in two vertical sedimentation cylinders with an inner diameter of 6 cm and a height of 60 cm and an inner diameter of 16 cm and a height of 320 cm. The sedimentation cylinder is filled with clean water and placed vertically, and the average value of multiple observations is determined as the test sedimentation velocity value according to the velocity measured when the test particles are put into the clean water and start to settle at a uniform speed, and the sedimentation velocity value of the model sand is determined to be similar to that of the tailings sand; In the large model water area, a disc with scales is placed at the bottom of the water area, and the model sand is allowed to naturally settle and form a mound in still water. The mound is formed on the disc, and the height and bottom radius of the mound are determined, and the slope of the mound is determined. It is determined that the underwater repose angle of the model sand is similar to the underwater repose angle of the tailings sand; According to the flume test, sedimentation test and repose angle test, the volume ratio of the target model sand was determined to be tailings: perlite = 3:2; the initial dam material was crushed foam bricks, and the model scale was 1:200; The tailings pond model is divided into 12 sections to record the dam breach evolution process; According to the evolution of dam breach, record the change process of breach flow at the dam site section, and draw the scouring and silting morphology diagram of each section in different time periods; Draw a tailings sedimentation status map based on the initial riverbed deep line, the deep line after dam breach, and the highest flood level; Determine the maximum flow range of the breach, the maximum flow velocity of the breach, and the amount of tailings sedimentation in the downstream channel according to a tailings pond model breach test; According to the time when the water flow of the tailings pond model reaches each key point after overflowing, the warning time and escape time of each key point are planned; According to the tailings pond model, after the dam burst, the tailings flow line and the schematic diagram of the flooding range are drawn, as shown in the figure. Figure 2 shown.

[0020] Example 2 This embodiment provides a simulation system for the impact of tailings dam overtopping and dam failure on downstream, including: The data collection module is configured to design a tailings pond overtopping and dam-break simulation test plan based on the topography, geology and design data of the tailings pond area and surrounding areas; A scheme determination module is configured to determine the model sand ratio and the model scale ratio according to the designed test scheme; The model building module is configured to establish a tailings dam breach physical model based on model sand selection and model scale selection; The test module is configured to perform a tailings dam breach test based on a tailings dam breach physical model; The analysis module is configured to analyze the dam break sedimentation volume and flooding range based on the test results. A computer-readable storage medium stores a plurality of instructions, wherein the instructions are suitable for being loaded and executed by a processor of a terminal device, and a method for simulating the impact of overtopping and dam breach of a tailings dam on the downstream is disclosed.

[0021] A terminal device includes a processor and a computer-readable storage medium, wherein the processor is used to implement various instructions; the computer-readable storage medium is used to store multiple instructions, wherein the instructions are suitable for being loaded and executed by the processor to simulate the impact of tailings pond overtopping and dam failure on downstream.

[0022] The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for simulating the impact of tailings dam overtopping and dam failure on downstream, characterized in that: include: Design a tailings pond overtopping and dam-break simulation test plan based on the tailings pond area and surrounding terrain, geology and design data; Determine the model sand ratio and model scale ratio according to the designed test plan; Establish the tailings dam break physical model based on the model sand selection and model scale selection; Conduct tailings dam breach test based on tailings dam breach physical model; The dam break sedimentation volume and flooding range are analyzed based on the test results.

2. The method for simulating the impact of tailings dam overtopping and dam failure on downstream according to claim 1, characterized in that: The method of designing a tailings pond overtopping and dam burst simulation test plan based on the tailings pond area and surrounding terrain, geology and design data includes collecting the tailings pond area and surrounding terrain, geology and design data, and designing a tailings pond overtopping and dam burst simulation test plan based on the tailings pond area and surrounding terrain, geology and design data.

3. The method for simulating the impact of tailings dam overtopping and dam failure on downstream according to claim 2, characterized in that: The model sand selection and model scale selection are determined according to the designed test plan, including a water tank test in a glass circulating water tank, adjusting the water flow through the upstream water measuring weir and the downstream tail gate of the water tank to form a quasi-binary uniform flow with a water surface gradient of about one ten-thousandth, determining the model sand selection according to the water tank test, and determining that the starting flow rate law of the model sand and the tailings sand is similar.

4. The method for simulating the impact of tailings dam overtopping and dam failure on downstream according to claim 3, characterized in that: The method of determining the model sand comparison and model scale comparison according to the designed test plan also includes placing a disc with scales on the bottom of the water area in the model, and allowing the model sand to naturally settle and form a mound in still water. The mound is formed on the disc, and the height and bottom radius of the mound are determined, the slope of the mound is determined, and it is determined that the underwater angle of repose of the model sand is similar to that of the tailings sand.

5. The method for simulating the impact of tailings dam overtopping and dam failure on downstream according to claim 4, characterized in that: The method of establishing a tailings dam break physical model based on model sand comparison and model size comparison includes conducting a tailings dam break pre-test based on the tailings dam break physical model to determine the best physical model establishment scheme.

6. The method for simulating the impact of tailings dam overtopping and dam failure on downstream according to claim 5, characterized in that: The tailings dam break pre-test based on the tailings dam break physical model includes testing whether the model sand is suitable for tailings dam break simulation; testing the relationship between the density and plasticity index of the tailings model dam body; and testing the influence of the construction method of the simulated dam break dam body model.

7. The method for simulating the impact of tailings dam overtopping and dam failure on downstream according to claim 6, characterized in that: The tailings dam break test based on the tailings dam break physical model includes determining the maximum flow range of the breach, the maximum flow velocity of the breach, and the amount of tailings sedimentation in the downstream channel according to the tailings dam break test model; planning the warning time and escape time of each key point according to the time when the water flow reaches each key point after overflowing the tailings dam model; and drawing a tailings flow trajectory and a schematic diagram of the flooded range after the overtopping and dam break of the tailings dam model.

8. A simulation system for the impact of tailings dam overtopping and dam failure on downstream, characterized in that: include: The data collection module is configured to design a tailings pond overtopping and dam-break simulation test plan based on the topography, geology and design data of the tailings pond area and surrounding areas; A scheme determination module is configured to determine the model sand ratio and the model scale ratio according to the designed test scheme; The model building module is configured to establish a tailings dam breach physical model based on model sand selection and model scale selection; The test module is configured to perform a tailings dam breach test based on a tailings dam breach physical model; The analysis module is configured to analyze the dam break sedimentation volume and flooding range based on the test results.

9. A computer-readable storage medium storing a plurality of instructions, characterized in that: The instructions are suitable for being loaded by a processor of a terminal device and executing the method according to claim 1 .

10. A terminal device, comprising a processor and a computer-readable storage medium, wherein the processor is used to implement each instruction; and the computer-readable storage medium is used to store multiple instructions, characterized in that: The instructions are suitable for being loaded by a processor and executing the method as claimed in claim 1 .

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