Prediction simulation device and method for converting two-dimensional value of landslide surge into three-dimensional value

Abstract

The prediction simulation device comprises a test water tank, an energy dissipation wall is arranged at one end of the test water tank, a sliding bed is arranged at the other end of the test water tank, a landslide body is laid on the sliding bed, a baffle is arranged at the front edge of the landslide body, and a pull rope type displacement meter is fixedly arranged at the top of the sliding bed. One end of a pull rope in the pull rope type displacement meter is connected with a sliding body placed in the landslide body, a plurality of wave height meters are arranged in the test water tank, and the pull rope type displacement meter and the wave height meters transmit detected data to a computer. According to the numerical simulation method capable of rapidly and accurately evaluating the landslide surge risk, the influence of complex underwater river terrains and river terrains on the landslide surge making and propagation process is considered, the water entering speed of a landslide body can be dynamically adjusted, information of a three-dimensional surge source is obtained through reconstruction and serves as an initial condition, and the three-dimensional surge risk is evaluated. The simulation of the surge propagation and climbing process is completed, the precision and efficiency of the simulation calculation result are greatly improved, and the consumption required by calculation is reduced.

Description

Technical Field

[0001] The invention relates to a prediction simulation device and method for converting a two-dimensional value of a landslide surge into a three-dimensional value. Background Art

[0003] Landslide-surge is the most common type of landslide-surge chain, which endangers the safety of large-scale and long-distance waterways, towns along the river, and the production and living areas of coastal residents. The landslide-surge chain has the characteristics of fast movement, wide disaster-causing areas caused by surges along the river, and strong suddenness.

[0004] The current research methods on landslide surge mainly include empirical formula method, theoretical formula method, generalized physical model test method and numerical simulation method. However, these methods have many limitations: 1. Limitations between the accuracy of calculation results and time and cost: From a theoretical analysis, in order to make the calculation results more accurate, more time and money need to be invested.

[0005] 2. Limitations of the cognitive level of the operator: All of the above methods require the operator to have a certain degree of understanding of them in order to grasp the applicability of each method, making it difficult to select appropriate methods for different cases.

[0006] 3. Limitations of computational models: Current research methods rarely consider the impact of complex underwater topography and river channel topography on the generation, propagation and rise of surge waves, making it difficult to improve the prediction accuracy of traditional methods.

[0007] Although there are many inventions based on physical model tests of landslide surges, it is difficult to quickly and accurately evaluate the danger of landslide surges due to the experimental conditions and feasibility. In addition, the dynamic evolution process of the landslide surge hazard chain is extremely complex, involving four processes: landslide impact wave generation-surge generation-propagation-climbing. A single research method is difficult to quickly and accurately simulate the entire process of the landslide surge hazard chain. At the same time, the landslide surge hazard chain is closely related to landslide movement, water bodies and river valley topography. The study of the landslide surge chain mechanism that deeply considers the landslide instability mode and the complex river valley terrain effect has been simplified or neglected in this field in the past, but it is the key to predicting the landslide surge hazard chain. Based on this, there is an urgent need for a numerical simulation method that can fully consider the influence of complex underwater river channel topography on surge generation, propagation and climbing processes, and quickly and accurately predict the entire process of the landslide surge hazard chain. Summary of the invention

[0008] The purpose of the present invention is to provide a prediction simulation device and method for converting two-dimensional values ​​of landslide surges into three-dimensional values, a numerical simulation method that can quickly and accurately evaluate the danger of landslide surges, taking into account the influence of complex underwater river terrain and river terrain on landslide wave generation and propagation processes, and being able to dynamically adjust the speed at which the landslide enters the water, and can achieve multi-calculation condition simulation. This paper simulates the impact wave generation process of the landslide through a two-dimensional single-width landslide surge physical model test, obtains the characteristic parameters of the first two-dimensional surge generated after the landslide becomes unstable, and reconstructs the information of the three-dimensional surge source through the surge maximum amplitude conversion formula, which is used as the initial condition for numerical simulation calculations to achieve simulation of far-field surge propagation and climbing processes, greatly improving the accuracy and efficiency of the simulation calculation results and reducing the cost required for calculations.

[0009] In order to solve the above problems, the technical solution of the present invention is: The prediction simulation device for converting two-dimensional values ​​of landslide surge into three-dimensional values ​​comprises a test water tank, one end of which is provided with an energy dissipation wall, the other end of which is provided with a slide bed, a landslide body is laid on the slide bed, a baffle is provided at the front edge of the landslide body, a pull-rope displacement meter is fixed on the top of the slide bed, one end of the pull rope in the pull-rope displacement meter is connected to a sliding body placed in the landslide body, a plurality of wave height meters are provided in the test water tank, and the pull-rope displacement meter and the wave height meter transmit the detected data to a computer.

[0010] Graph paper is pasted on the inner wall of the test tank.

[0011] Anti-slip tape is pasted on the landslide body.

[0012] An electromagnet is fixedly installed in the water tank, one end of the baffle is fixedly connected to an armature, the armature is adsorbed on the electromagnet, a telescopic rod is arranged outside the test water tank, a guide wheel is installed on the top of the telescopic rod, a nylon rope is arranged on the guide wheel, one end of the nylon rope is connected to the baffle, and the other end of the nylon rope is connected to the counterweight block.

[0013] A method for predicting and simulating a landslide surge by converting a two-dimensional value into a three-dimensional value comprises the following steps: Step 1: First, the armature at one end of the baffle is adsorbed on the electromagnet, and then the height of the guide wheel is adjusted by adjusting the height of the telescopic rod, thereby adjusting the angle between the baffle and the horizontal plane to a set angle; Step 2: After laying the landslide mass on the slide bed, water is poured into the test water tank; Step three, the electromagnet loses power, the baffle is released, and the landslide body flows into the test water tank. At the same time, the pull-wire displacement meter and wave height meter will transmit the detected data to the computer, which will store and calculate the data information transmitted by the pull-wire displacement meter and wave height meter.

[0014] Step 4: Obtain the motion characteristic parameters of the landslide body and the morphological characteristic parameters of the initial surge wave by solving the images, displacement meter and wave height meter data of the test process.

[0015] Step 5: Based on the surge amplitude conversion formula, the maximum amplitude of the two-dimensional landslide surge (A MAX,2D，P ) is converted into the maximum amplitude of the surge wave in three-dimensional form (A MAX，3D，P ); and through Froude similarity theory, the motion characteristic parameters of the landslide body (motion time (T 2D，M ), movement speed (V 2D，M )、Movement distance (S 2D，M )) and the morphological characteristic parameters of the initial surge wave (maximum amplitude (A MAX,2D，P ), wavelength (L MAX，2D，M ))Converted to true value.

[0016] Step six, integrate the motion characteristic parameters of the landslide body under real conditions and the morphological characteristic parameters of the initial surge wave, reconstruct the wave source morphology of the initial maximum surge wave, and use the fully nonlinear Boussinesq equation in the basic control equation of fluid mechanics to perform numerical simulation calculations on the surge propagation and climbing process, and obtain the propagation and climbing process of the far-field surge wave.

[0017] The beneficial effects of the present invention are: (1) The present invention is based on a three-dimensional landslide surge hazard chain numerical simulation method coupled with a two-dimensional physical model test. Through the two-dimensional physical model test of landslide surge, the material properties of the landslide body and the morphological characteristics of the landslide and underwater topography of the river channel can be fully considered, and the influence of the landslide impact wave-making process under complex underwater topography can be fully considered.

[0018] (2) The two-dimensional physical model test of landslide surge can observe the interaction process between landslide and water in detail. The particle image velocimetry technology can be used to calculate the instantaneous full-field velocity vector data of the entire process of landslide and water movement, and analyze the interaction law between landslide and water body and the energy transfer and energy dissipation mechanism during the landslide impact wave-making stage.

[0019] (3) Based on the surge wave amplitude conversion formula, the maximum amplitude of the two-dimensional surge wave can be linked to the maximum amplitude of the three-dimensional surge wave, which can solve the limitations of the two-dimensional single-width water tank test of landslide surge waves and eliminate the influence of the lateral limitation of the surge wave on the test results, so that the test results can meet the requirements of three-dimensional conditions and greatly improve the accuracy and convenience of the calculation results.

[0020] (4) This paper provides a three-dimensional landslide surge hazard chain numerical simulation method coupled with a two-dimensional physical model test, which can break the time-consuming and costly limitations of large-scale three-dimensional physical model tests. The hybrid method can greatly improve the simplicity of the test process and the accuracy of the test results. It provides a technical process for quickly and accurately evaluating the hazard of landslide surges. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below in conjunction with the accompanying drawings: Figure 1 is a flow chart of the present invention, Figure 2 is a schematic diagram of the structure of the device of the present invention, Figure 3 for Figure 2 The local enlarged structural diagram at A in the middle, Figure 4 This is a numerical simulation calculation model diagram of landslide surge in the present invention. Figure 5 This is the result diagram of the numerical simulation of landslide surge in the present invention. Figure 6 This is the landslide surge intensity zoning diagram of the present invention, Figure 7 It is a schematic diagram of the intensity of landslide surge in the present invention.

[0022] In the figure: test water tank 1, energy dissipation wall 2, computer 3, graph paper 4, wave height meter 5, baffle 6, sliding body 7, anti-slip tape 8, pull-rope displacement meter 9, guide wheel 10, counterweight 11, telescopic rod 12, slide bed 13, electromagnet 14, landslide body 15, armature 16, three-dimensional reconstruction surge source 17, extremely high surge intensity area 18, very high surge intensity area 19, high surge intensity area 20, medium surge intensity area 21, water body 22, river channel topography 23. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] like Figure 2 and 3As shown, a prediction simulation device for converting a two-dimensional value of a landslide surge into a three-dimensional value comprises a test flume 1, an energy dissipation wall 2 is arranged at one end of the test flume 1, a slide bed 13 is arranged at the other end, a landslide body 15 is laid on the slide bed 13, a baffle 6 is arranged at the front edge of the landslide body 15, a pull-rope displacement meter 9 is fixedly arranged on the top of the slide bed 13, one end of the pull rope in the pull-rope displacement meter 9 is connected to a sliding body 7 placed in the landslide body 15, a plurality of wave height meters are arranged in the test flume 1, and the pull-rope displacement meter 9 and the wave height meter transmit the detected data to a computer 3.

[0025] Graph paper 4 is pasted on the inner wall of the test water tank 1. The background of the graph paper 4 is used as a scale to facilitate reading the wavelength and amplitude when the first column of maximum surge waves is generated and to determine the type of surge waves.

[0026] An anti-skid tape 8 is attached to the landslide body 15. The PVC anti-skid tape 8 arranged on the slide bed 13 is used to change the friction coefficient between the contact surface of the landslide body 15 and the slide bed 13 to control the acceleration of the landslide body 15 during movement, thereby controlling the water entry speed of the landslide body 15 and simulating the impact wave-making process under various instability scenarios.

[0027] An electromagnet 14 is fixedly arranged in the water tank, an armature 16 is fixedly connected to one end of the baffle 6, and the armature 16 is adsorbed on the electromagnet 14. A telescopic rod 12 is arranged outside the test water tank 1, and a guide wheel 10 is installed on the top of the telescopic rod 12. A nylon rope is arranged on the guide wheel 10, one end of the nylon rope is connected to the baffle 6, and the other end of the nylon rope is connected to the counterweight 11. The electromagnet 14 is convenient for releasing the baffle 6 and adjusting the angle of the baffle 6, so as to simulate the angle of a three-dimensional real landslide.

[0028] Taking the Wangjiashan landslide in the Baihetan reservoir area as an example, the method of using the prediction simulation device is further described below. The method includes the following steps: Before doing the experiment, you need to build a prediction simulation device. The construction method includes the following steps: A: Using the main sliding profile of Wangjiashan landslide and the Jinsha River channel profile, based on the Froude similarity criterion, the landslide body 15 and the dimensions of the river channel were scaled to a scale of 1:200 to establish a two-dimensional single-width landslide surge test flume 1 of Wangjiashan landslide.

[0029] B: Determine the similar material of the landslide body 15 in the model test. According to the density similarity principle, the material of the Wangjiashan landslide body 15 is selected according to the density ratio of 1:1. The similar material of the Wangjiashan landslide body 15 is composed of iron sand and river sand particles mixed in a ratio of 7:3, and the natural bulk density is about 2.1kg / m 3 .

[0030] C: A 0.5m long and 0.5m wide anti-skid tape 8 is pasted in the middle of the slide bed 13 to change the speed at which the landslide body 15 enters the water. If the speed is increased, the length of the anti-skid tape 8 needs to be reduced; if the speed is reduced, the length of the anti-skid tape 8 needs to be increased.

[0031] D: Five wave height meters are arranged in the river channel to collect wave amplitude change data.

[0032] Step 1: First, the armature 16 at one end of the baffle 6 is adsorbed on the electromagnet 14, and then the height of the guide wheel 10 is adjusted by adjusting the height of the telescopic rod 12, thereby adjusting the angle between the baffle 6 and the horizontal plane to the angle of the front edge of the Wangjiashan landslide, and using similar materials of the Wangjiashan landslide body 15 to pile up from bottom to bottom in the test water tank 1 to form the Wangjiashan landslide body 15, and burying the sliding body 7 in the landslide body 15 during the piling process; Step 2: After laying the landslide body 15 on the slide bed 13, water is poured into the test water tank 1; In step three, the electromagnet 14 loses power, the baffle 6 is released, and the landslide body 15 flows into the test water tank 1. At the same time, the pull-wire displacement meter 9 and the wave height meter transmit the detected data to the computer 3, which stores and calculates the data information transmitted by the pull-wire displacement meter 9 and the wave height meter.

[0033] Step 4: The movement time (T 2D )、Movement distance (S 2D ), the movement speed (V 2D At the same time, the image when the first wave produces the maximum amplitude is interpreted based on the image interpretation method, and the background of the test tank 1 and the square paper 4 are used as the scale to read the wavelength (L MAX,2D，M ) and amplitude (A MAX,2D，M ) and determine the surge wave type.

[0034] According to the Froude similarity principle, the test results of various parameters in the two-dimensional single-width landslide surge physical model test of Wangjiashan landslide are converted into true values ​​according to a certain proportional relationship. L is 200, speed scale μ V is 14.14, flow rate scale μ Q is 1788.5, the time scale is μ T is 14.14, density scale μ ρ = 1, and the motion characteristic parameters of the Wangjiashan landslide body 15 and the morphological characteristic parameters of the first surge under real conditions are obtained, specifically T 3D，P =14.14 × T2D，M =50.9s, S 3D，P =200× S2D，M =211.4m, V 3D，P =14.14×V 2D，M =7.07m / s, L MAX，3D，P =200×L MAX，3D，M =785.4m,W 3D,p =1062.6m.

[0035] The surge amplitude conversion formula is used to convert the maximum amplitude of the two-dimensional surge wave into a three-dimensional value. The surge amplitude expansion formula is: A MAX，3D，P =200×A MAX，2D，M ×(w 3D，P / (w 3D，P +L MAX，3D，M ))=11.5m.

[0036] Step five, the computer 3 uses the motion characteristic information of the Wangjiashan landslide body 15 and the first column of surge morphological characteristic parameters obtained above to form morphological characteristic parameters of a three-dimensional initial surge source, reconstruct the initial surge source with a real free surface shape, and form a calculation file with velocity field and potential field.

[0037] The computer 3 uses the three-dimensional initial surge source information as the initial control condition and adopts the water wave dynamics method to calculate the surge propagation and climbing process using the full nonlinear Boussinesq equation in the basic control equation of fluid mechanics, thereby simulating the surge propagation and climbing process.

[0038] Among them, the mass conservation equation of the fully nonlinear Boussinesq equation is:

[0039] Among them, the momentum conservation equation of the fully nonlinear Boussinesq equation is:

[0040] Where H is the water surface height in m, Hw is the water depth in m, is the horizontal velocity at water depth Hw in m / s; T is the partial derivative with respect to time.

[0041] According to the above calculation results, the intensity levels of surges in the Jinsha River are zoned according to the maximum amplitude and climbing height of surges in each area of ​​the Jinsha River.

[0042] Among them, when the surge amplitude / height is greater than 2.0m, it is an extremely high surge danger zone; when 1.5m is less than the surge amplitude / height ≤2.0m, it is a very high surge danger zone; when 1.0m is less than the surge amplitude / height ≤1.5m, it is a high surge danger zone; when 0.5m is less than the surge amplitude / height ≤1.0m, it is a medium surge danger zone; and when the surge amplitude / height ≤0.5m, it is a low surge danger zone.

[0043] The contents described in the embodiments of this specification are merely an enumeration of the implementation forms of the inventive concept. The protection scope of the present invention should not be regarded as limited to the specific forms described in the embodiments. The protection scope of the present invention also extends to equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. A prediction and simulation device for converting two-dimensional values ​​of landslide surge into three-dimensional values, characterized in that: The invention comprises a test water tank (1), wherein an energy dissipation wall (2) is arranged at one end of the test water tank (1), and a slide bed (13) is arranged at the other end. A landslide body (15) is laid on the slide bed (13), a baffle (6) is arranged at the front edge of the landslide body (15), a pull-rope displacement meter (9) is fixedly arranged on the top of the slide bed (13), one end of the pull rope in the pull-rope displacement meter (9) is connected to a sliding body (7) placed in the landslide body (15), and a plurality of wave height meters are arranged in the test water tank (1), and the pull-rope displacement meter (9) and the wave height meter transmit detected data to a computer (3).

2. The prediction and simulation device for converting two-dimensional values ​​of landslide surge into three-dimensional values ​​according to claim 1, characterized in that: Graph paper (4) is pasted on the inner wall of the test water tank (1).

3. The prediction and simulation device for converting two-dimensional values ​​of landslide surge into three-dimensional values ​​according to claim 1, characterized in that: An anti-slip tape (8) is pasted on the landslide body (15).

4. The prediction and simulation device for converting two-dimensional values ​​of landslide surge into three-dimensional values ​​according to any one of claims 1 to 3, characterized in that: An electromagnet (14) is fixedly arranged in the water tank, an armature (16) is fixedly connected to one end of the baffle (6), and the armature (16) is adsorbed on the electromagnet (14). A telescopic rod (12) is arranged outside the test water tank (1), a guide wheel (10) is installed on the top of the telescopic rod (12), and a nylon rope is arranged on the guide wheel (10), one end of the nylon rope is connected to the baffle (6), and the other end of the nylon rope is connected to the counterweight (11).

5. A method for predicting and simulating the landslide surge two-dimensional value conversion to three-dimensional value using the device for predicting and simulating the landslide surge two-dimensional value conversion according to claim 4, characterized in that: The steps include: Step 1: firstly, the armature (16) at one end of the baffle (6) is adsorbed on the electromagnet (14), and then the height of the guide wheel (10) is adjusted by adjusting the height of the telescopic rod (12), thereby adjusting the angle between the baffle (6) and the horizontal plane to a set angle; Step 2: After laying the landslide body (15) on the slide bed (13), water is poured into the test water tank (1); Step 3: the electromagnet (14) loses power, the baffle (6) is released, and the landslide body (15) flows into the test water tank (1). At the same time, the pull-wire displacement meter (9) and the wave height meter transmit the detected data to the computer (3), and the computer (3) stores and calculates the data information transmitted by the pull-wire displacement meter (9) and the wave height meter; Step 4: According to the data information, the morphological characteristics of the initial surge wave formed after the landslide fails are obtained, and based on the surge wave amplitude expansion formula, a three-dimensional initial surge source is constructed as the input value of the numerical simulation calculation to simulate the propagation and climbing process of the far-field surge wave. The surge wave amplitude expansion formula is: A MAX,3D,P =200×A MAX,2D,M ×(w 3D,P / (w 3D,P +L MAX，3D，M ))。

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