A hydraulic transmission type coal mine landslide speed control device and test method

Abstract

The present invention belongs to the field of mining engineering and information technology, and discloses a hydraulic transmission type coal mine landslide speed control device and test method. The method includes: prototype analysis and similarity coefficient determination; similar material formulation design; material property inspection, detection of material physical and mechanical properties; test parameter calculation, based on similarity theory and landslide dynamics principles, using mathematical and numerical methods to calculate the expected speed, acceleration distance and parking height; sensor layout, material box angle adjustment, landslide model test and material box cleaning and maintenance. The test method provided by the present invention has the characteristics of simple operation, low cost and high repeatability, which is convenient for conducting experimental research on landslide speed control under diverse geological conditions. The landslide speed control device and its test method of the present invention can significantly improve the efficiency and safety of landslide prevention and control work, and reduce the damage caused by landslide disasters to human society and the natural environment.

Description

Technical Field

[0001] The invention belongs to the fields of mining engineering and information technology, and in particular relates to a hydraulic transmission type coal mine landslide speed control device and a test method. Background Art

[0002] Due to geological factors and other factors, many coal mines are located in high mountain valleys during mineral resource extraction. This exacerbates slope instability, leading to frequent disasters such as collapses, landslides, and mudslides. These geological hazards not only pose significant challenges to underground mining but also threaten the surrounding environment and the safety of people and property. Slope landslides typically occur due to a combination of factors, including geological conditions, external loading, and rainfall. The immense impact of the sliding landslide not only causes deformation and damage to the surface but also has direct impacts on underground tunnels and worksites. These impacts include deformation and damage to tunnels, and even the possibility of tunnel closure. Furthermore, landslides can disrupt groundwater conditions, potentially causing water levels to rise or fall, impacting mine drainage and ventilation systems, increasing safety risks, and reducing mining efficiency.

[0003] Coal mine landslide model tests can visually demonstrate the process of landslide instability and fall, and are considered an important method for effectively simulating coal mine landslides. Under conditions that meet similarity criteria, coal mine landslide model tests can study the sliding patterns of landslides and effectively predict the scope and severity of coal mine landslide disasters, providing an important basis for implementing effective coal mine landslide prevention and mitigation measures.

[0004] Through the above analysis, the problems and defects of the existing technology are as follows: traditional mechanical structures (such as gears and chains) have slow response speeds and cannot accurately match the dynamic changes of landslides, which can easily lead to control lag or excessive intervention; and existing landslide simulation devices mostly rely on physical models or numerical calculations, and lack the ability to reproduce real working conditions in real time. Summary of the Invention

[0005] To overcome the problems of the existing technology, the disclosed embodiments of the present invention provide a hydraulically driven coal mine landslide velocity control device and test method. The design of the device and implementation of the test method provide a more accurate and scientific experimental basis for landslide prevention and control, thereby improving the efficiency and safety of landslide prevention and control work.

[0006] The technical solution is as follows: A test method for a hydraulically driven coal mine landslide speed control device comprises the following steps:

[0007] S1, prototype analysis and similarity coefficient determination;

[0008] S2, similar material formulation design;

[0009] S3, testing the physical and mechanical properties of materials;

[0010] S4, based on similarity theory and landslide dynamics principles, use mathematical and numerical methods to calculate the expected speed, acceleration distance and parking height;

[0011] S5: Determine the type, quantity, and location of sensors based on the characteristics of landslide movement and observation requirements, monitor and record changes in landslide movement parameters, and form a complete monitoring network;

[0012] S6, material box angle adjustment, adjust the material box rotation angle according to the similarity coefficient and the prototype tilt angle;

[0013] S7, conduct landslide model test and material box cleaning and maintenance.

[0014] In step S1, prototype analysis and similarity coefficient determination include:

[0015] S101: Analyze the geological conditions of the prototype landslide and complete the quantitative characterization of the landslide model;

[0016] S102, determine the similarity coefficient of the model test based on similarity theory; in the landslide model test, the basic dimension is mass length and time ; Select geometry, mechanics and motion as dimensionally independent basic quantities, and establish similarity relationships among physical quantities based on dimensional analysis:

[0017] Geometric parameters:

[0018] ;

[0019] Where, is the geometric scale factor between the model and the prototype, is the prototype characteristic length, is the model characteristic length;

[0020] Mechanical parameters, elastic modulus similarity ratio is:

[0021] ;

[0022] Where, is the proportional coefficient of elastic modulus between the model and the prototype, is the stress proportionality coefficient between the model and the prototype;

[0023] The similarity ratio of permeability coefficient is:

[0024] ;

[0025] Where, is the proportional coefficient between the model and prototype permeability coefficients, is the time ratio coefficient between the model and the prototype;

[0026] Dynamic parameters, acceleration similarity ratio:

[0027] ;

[0028] Where, is the acceleration proportional coefficient between the model and the prototype;

[0029] Speed similarity ratio:

[0030] ;

[0031] Where, is the speed ratio coefficient between the model and the prototype;

[0032] Displacement:

[0033] ;

[0034] Where, is the displacement proportional coefficient between the model and the prototype.

[0035] In step S2, similar materials are formulated and designed, including:

[0036] Constrained by the mechanical similarity ratio in similarity theory, the orthogonal experimental method was used to optimize the composite ratio of aggregate, cementitious agent, and toughening phase, and the porosity and permeability were balanced by controlling the water-cement ratio and gradation curve. Finally, triaxial shear and creep tests were conducted to verify the strain hardening, dilatancy, and long-term stability of the model material, ensuring that the stress-strain curve was consistent with that of the prototype rock and soil at a normalized scale, thus achieving cross-scale equivalent simulation of geomechanical behavior.

[0037] In step S3, the physical and mechanical properties of the material are detected, including:

[0038] S301, physical properties testing;

[0039] Density and porosity, wet density determined by the knife ring method , combined with the drying method to calculate the porosity , is the dry density, is the particle density, and the pore distribution of heterogeneous materials is corrected by the improved fractal pore model, which is expressed as:

[0040] ;

[0041] Where, is the corrected effective porosity, is the initial porosity calculated by traditional method, are the maximum and minimum pore diameters, is the pore fractal dimension, which was calibrated by the SEM image box counting method;

[0042] Permeability coefficient, based on variable head permeability test data, introduces non-Darcy flow correction factor :

[0043] ;

[0044] Where, is the corrected permeability coefficient, is the experimentally measured permeability coefficient, is the hydraulic gradient, is the critical gradient;

[0045] S302, mechanical properties testing;

[0046] Shear strength parameters, cohesion obtained by direct shear test or triaxial test and internal friction angle ,Combined with the nonlinear intensity envelope model to optimize the similarity ratio, the expression is:

[0047] ;

[0048] Where, is the cohesion similarity ratio, is the density similarity ratio, is the stress level correction factor, is the normal stress, is the reference stress, is the geometric scale factor between the model and the prototype;

[0049] The deformation modulus is characterized by the strain hardening effect using the triaxial test stress-strain curve and piecewise power function fitting, and the expression is:

[0050] ;

[0051] Where, is the initial modulus, is the critical strain, is the hardening index, is the deformation modulus, For strain.

[0052] In step S4, the expected speed, acceleration distance, and parking height are calculated using mathematical and numerical methods based on similarity theory and landslide dynamics principles, including:

[0053] S401, Dynamic modeling and similarity law correction;

[0054] Assuming that the sliding body is subject to gravity, base friction and internal shear resistance, the motion equation is:

[0055] ;

[0056] Where, is the mass of the landslide, is the landslide velocity, For time, is the acceleration due to gravity, is the sliding surface contact area, is the inclination angle of the material box, is the base friction coefficient, is the shear strength of sliding zone soil, ; For cohesion, is the internal friction angle;

[0057] Similarity Scaling: Convert prototype parameters to model parameters according to the Froude similarity criterion:

[0058] ;

[0059] ;

[0060] ;

[0061] Where, is the speed in the model experiment, is the actual velocity of the prototype landslide, is the acceleration in the model experiment, is the actual acceleration of the prototype landslide, is the shear strength of the model material, is the shear strength of the model landslide;

[0062] S402, numerical solution and acceleration distance calculation;

[0063] The improved Runge-Kutta method discretizes the equation of motion into:

[0064] ;

[0065] The fourth-order Runge-Kutta method is used to iteratively solve the velocity and displacement:

[0066] ;

[0067] ;

[0068] ;

[0069] ;

[0070] ;

[0071] ;

[0072] Where, are the slopes of the Runge-Kutta method, For the The speed of the time step, For the The displacement of the time step, is the time step, For the The speed of the time step, For the The time point of the time step, For the The displacement of the time step;

[0073] The acceleration distance is defined as the time when the speed reaches a stable value Displacement , by monitoring the speed change rate , determine convergence;

[0074] S403, parking height calculation and energy conservation correction;

[0075] Energy balance equation, the sliding body from the initial height Slide to parking height , the mechanical energy loss is friction work:

[0076] ;

[0077] Where, is the total sliding distance of the landslide from the beginning of sliding to complete stop, is the displacement variable on the sliding path;

[0078] Numerical integration is used to discretize the sliding path into Segment, displacement increment for each segment , iterative calculation of parking height:

[0079] ;

[0080] Where, For the The parking height calculated by the iteration is For the The friction coefficient on the sliding path, For the Shear strength over the sliding distance, For the Displacement increment over the sliding distance;

[0081] Introducing speed-dependent friction coefficient , enhance the nonlinear characterization capability of the model, is the rate effect coefficient, is the basic friction coefficient, is the instantaneous velocity of the landslide.

[0082] In step S5, the sensor type, quantity and location are determined, including:

[0083] Displacement monitoring, using laser displacement meters and high-frequency InSAR, covering the sliding surface;

[0084] Acceleration acquisition, triaxial MEMS accelerometers are embedded in the sliding body and arranged in a hexahedral grid, with the node spacing determined by the thickness of the sliding body. Decide, ;

[0085] Strain field capture, distributed fiber optic sensing is laid along the sliding belt.

[0086] In step S6, adjusting the rotation angle of the material box includes:

[0087] The tilt angle of the tilt truss is controlled by controlling the elongation of the flip cylinder fluid, and the tilt angle of the landslide material is controlled; the initial elongation of the flip cylinder, the distance from the flip cylinder to the flip support seat, and the distance from the intersection of the flip support seat and the tilt truss to the intersection of the flip cylinder and the tilt truss are formed into a triangle; the initial length of the flip cylinder is The corresponding initial angle is , the distance from the top of the flip cylinder to the flip support seat is The distance from the intersection of the flip support seat and the tilt truss to the intersection of the flip cylinder and the tilt truss is ; Assume that the inclination angle of the prototype landslide is , when the triangle angle is arrive When the hydraulic jack extends ;Establish and Function expression of ;

[0088] By the law of cosines:

[0089] ;

[0090] When the side becomes After that, the corresponding angle satisfy:

[0091] ;

[0092] Subtract these two equations:

[0093] ;

[0094] Arranged:

[0095] .

[0096] In step S7, a landslide model test and material box cleaning and maintenance are performed, including: using a high-speed camera and a data acquisition system to observe and record the entire landslide movement process and record abnormalities;

[0097] Material box cleaning and maintenance include: cleaning the material box in time after the test, removing residual materials, and inspecting and maintaining structures and components.

[0098] Another object of the present invention is to provide a hydraulically driven coal mine landslide speed control device, which implements the test method of the hydraulically driven coal mine landslide speed control device. The device includes: a material box for containing landslide material and a tilting truss located below the material box for fixing the acceleration mechanism, and a tilting cylinder for adjusting the angle of the material box; the tilting truss is connected to the base truss via the tilting cylinder; the front end of the base truss is provided with a tilting support seat; the tilting cylinder is installed at the rear end of the base truss;

[0099] A high-speed oil cylinder, a guide rod, and a guide rail are installed in the inclined truss, and a power source is provided to the material box 1 through the high-speed oil cylinder;

[0100] A card slot is provided at the bottom of the material box, and a buckle is installed at the bottom of the material box; the buckle is matched in the card slot;

[0101] A hydraulic door opening device is installed on the side of the front edge of the material box, and the hydraulic door opening device includes a baffle lock, a hydraulic rod and a material box door opening device; the baffle lock and the hydraulic rod are used in conjunction with each other. When the front edge of the material box is accelerated to the front end of the inclined truss, the baffle lock is pulled by the hydraulic rod and rotates upward, and the front side baffle of the material box door opening device is pulled by the spring device, which opens the front side baffle of the material box door opening device and releases the landslide material in the material box.

[0102] Furthermore, the buckle is engaged with the front of the high-speed oil cylinder, and the high-speed oil cylinder gives power to the material box, thereby driving the material box to accelerate downward along the longitudinal guide rail through multiple pulleys installed at the bottom of the material box. The buckle is connected to the guide rod, and the guide rod is matched in the card slot;

[0103] The flip support seat provided at the front end of the base truss is used as the support point when the tilt truss is flipped. The telescopic length of the flip cylinder provided at the rear end is controlled to control the tilt angle of the tilt truss, thereby controlling the angle of the material box.

[0104] Combined with all the above-mentioned technical solutions, the present invention offers the following advantages: It boasts a simple structure and ease of operation. It overcomes the slow response of traditional mechanical structures (such as gears and chains), which cannot accurately match the dynamic changes of landslides and can easily lead to control lag or excessive intervention. Furthermore, existing landslide simulation devices often rely on physical models or numerical calculations, lacking the ability to reproduce real-world conditions in real time. By incorporating a material bin, tilting trusses, high-speed cylinders, and guide rods, the present invention precisely controls the speed of the landslide, simulating its motion under various environmental conditions and providing scientific theoretical support for landslide prevention and control efforts. The ingenious design, with its material bin door opening mechanism and baffle lock, enables the automatic release of landslide materials. By incorporating a tilting cylinder into the base truss, it enables the physical simulation of landslides at varying inclination angles, expanding the applicability of the landslide acceleration device. By adjusting experimental parameters, it is possible to further investigate the mechanisms by which various prevention and control strategies affect the motion of the landslide and to recreate the motion characteristics of the landslide in a natural environment. Furthermore, the test method provided by the present invention is simple to operate, cost-effective, and highly reproducible, facilitating experimental research on landslide velocity control under diverse geological conditions. In practical applications, the landslide velocity control device and its test method can significantly improve the efficiency and safety of landslide prevention and control efforts, reducing the damage caused by landslide disasters to human society and the natural environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0105] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure;

[0106] Figure 1 This is a schematic diagram of a hydraulic transmission type coal mine landslide speed control device provided by an embodiment of the present invention;

[0107] Figure 2 It is a side view of a hydraulic transmission type coal mine landslide speed control device provided by an embodiment of the present invention;

[0108] Figure 3 2 is a three-dimensional schematic diagram of a landslide velocity control device according to an embodiment of the present invention;

[0109] Figure 4 This is a side view of a material box door opening device in a hydraulic transmission type coal mine landslide speed control device provided by an embodiment of the present invention;

[0110] Figure 5 This is a schematic diagram of the working of the baffle lock and door opening device in the hydraulic transmission type coal mine landslide speed control device provided by an embodiment of the present invention;

[0111] Figure 6The invention provides a method for testing a hydraulically driven coal mine landslide speed control device.

[0112] In the figure: 1. Material box; 2. Guide rail; 3. Guide rod; 4. Tilt truss; 5. Turn cylinder; 6. Turn support seat; 8. Pulley; 9. Base truss; 10. Hydraulic rod; 11. Baffle lock; 12. Material box door opening device; 13. Spring device; 14. Buckle. DETAILED DESCRIPTION

[0113] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0114] The innovation of the present invention lies in: the present invention systematically solves the technical problem of dynamic control of coal mine landslide velocity through high-precision hydraulic control and multi-field coupling test method; the sliding velocity of the model landslide is accurately controlled by a hydraulic device, reducing the error between the sliding velocity of the model and the prototype landslide; and the chemical, physical and mechanical properties of the model material are made consistent with those of the prototype landslide through the multi-field coupling test method.

[0115] Example 1, as Figure 1-Figure 5 As shown, the hydraulic transmission type coal mine landslide speed control device provided by the embodiment of the present invention includes a material box 1 for containing landslide material, a tilting truss 4 located below the material box and used to fix the acceleration mechanism, and a tilting cylinder 5 for adjusting the angle of the material box 1; the tilting truss 4 is connected to the base truss 9 through the tilting cylinder 5; wherein, the front end of the base truss 9 is provided with a tilting support 6; the tilting cylinder 5 is installed at the rear end of the base truss 9;

[0116] A high-speed oil cylinder 7, a guide rod 3, and a guide rail 2 are installed in the inclined truss 4, and the high-speed oil cylinder 7 provides a power source to the material box 1;

[0117] A card slot (not shown) is provided at the bottom of the material box 1, and a buckle 14 is installed at the bottom of the material box 1; the buckle 14 is matched in the card slot;

[0118] The buckle 14 engages with the front of the high-speed cylinder 7, which imparts power to the material box 1, thereby accelerating the downward movement of the material box 1 along the longitudinal guide rail 2 via multiple pulleys 8 mounted at the bottom of the material box 1. The pulleys 8 are accommodated within the guide rail 2 and can roll freely. The buckle 14 is connected to the guide rod 3, which fits within the slot. The guide rod 3 prevents the material box 1 from deflecting during movement. The buckle 14 is able to slide freely on the surface of the inclined truss 4.

[0119] like Figure 3-Figure 5 A hydraulic door opening device is installed on the side of the front edge of the material box 1, and the hydraulic door opening device includes a baffle lock 11, a hydraulic rod 10 and a material box door opening device 12; the baffle lock 11 is used in conjunction with the hydraulic rod 10. When the front edge of the material box 1 is accelerated to the front end of the inclined truss 4, the baffle lock 11 is pulled by the hydraulic rod 10 and rotates upward, and the front side baffle of the material box door opening device 12 is pulled by the spring device 13, which can timely open the front side baffle of the material box door opening device 12 to release the landslide material in the material box 1.

[0120] A flip support seat 6 is provided at the front end of the base truss 9, which is used as the support point when the tilt truss 4 is flipped. A flip cylinder 5 is provided at the rear end. The tilt angle of the tilt truss 4 is controlled by controlling the telescopic length of the flip cylinder 5, thereby controlling the angle of the material box 1.

[0121] Exemplarily, the high-speed cylinder 7 provides power to the material box 1 so that the material box moves along the longitudinal guide rail 2 at a predetermined speed.

[0122] The material box 1 is configured to be rectangular, and the baffles on both sides are made of high-strength transparent organic glass, so that the changes in the materials in the material box 1 can be clearly seen.

[0123] When the material box 1 reaches a certain position at the front end of the inclined truss 4, the opening and closing of the baffle lock 11 can be accurately controlled by controlling the hydraulic door opening device, so that the material in the material box 1 can slide out.

[0124] A flip support seat 6 is provided at the front end of the base truss 9 to provide a support point for the tilting truss 4 when flipping. A flip cylinder 5 is provided at the rear end. By controlling the telescopic length of the flip cylinder 5, the tilt angle of the tilting truss 4 is controlled, and then the tilt angle of the material box 1 is controlled.

[0125] As can be seen from the above embodiments, the hydraulically driven coal mine landslide speed control device provided by the present invention cleverly integrates hydraulic technology and mechanical engineering principles. The device primarily comprises: a material box for loading the landslide material, and a hydraulic door opening mechanism disposed at the front end of the material box; a tilting truss for securing the material box and the acceleration mechanism, which includes a high-speed oil cylinder for speed control, a guide rod to prevent the material box from deviating, and a guide rail to ensure smooth movement of the material box; a base truss 9 with a tilting support 6 at the front end, through which the tilting truss is connected to the base truss 9; and a tilting oil cylinder 5 at the rear end for adjusting the angle of the tilting truss.

[0126] A high-speed cylinder 7 is mounted on top of the tilted truss. Its front end is equipped with a clip 14, which fits into a corresponding slot on the bottom of the material box. This clip and slot connect the high-speed cylinder to the material box. As a power output unit, the high-speed cylinder provides power to the material box, enabling it to move at a predetermined speed, thereby precisely controlling the speed of landslide release.

[0127] The front end of the high-speed cylinder is also equipped with a guide rod. The addition of the guide rod further improves the stability and accuracy of the material box during the release process, and effectively avoids the deviation or swing problems that may occur during the movement of the landslide body.

[0128] The material box 1 is set to be rectangular, and the baffles on both sides are made of high-strength transparent organic glass. The destruction characteristics of the landslide body can be observed during the test.

[0129] A hydraulic door opening device is provided at the front end of the material box 1, and the baffle lock 11 is used in conjunction with the hydraulic rod 10. When the front edge of the material box is accelerated to the end of the guide rail 2, the baffle lock 11 of the hydraulic door opening device is controlled to rotate upward by the pulling force of the hydraulic rod 10, and the front side baffle of the material box door opening device 12 is pulled by the spring device 13, so that the material box can be opened in time to release the landslide material in the material box 1.

[0130] In order to achieve angle control between the material box and the base truss 9, a flip support seat 6 is provided at the front end of the base truss 9, which is used as the support point when the tilt truss is flipped. A flip cylinder 5 is provided at the rear end. By controlling the telescopic length of the flip cylinder 5, the tilt angle of the tilt truss 4 is controlled, and then the angle of the material box 1 is controlled.

[0131] Example 2, as Figure 6 As shown, the test method of the hydraulic transmission type coal mine landslide speed control device provided by the present invention includes the following steps:

[0132] S1, prototype analysis and similarity coefficient determination;

[0133] S101 meticulously analyzed the geological conditions of the prototype landslide. Regional geological maps, drill core data, geophysical exploration data (such as resistivity and seismic waves), topographic remote sensing images, and long-term displacement monitoring records were systematically collected to establish a unified geographic information database. Three-dimensional geological modeling software was used to spatially interpolate and reconstruct stratigraphic interfaces, structural surface networks, and groundwater levels. Kriging was used to eliminate data discreteness. Probabilistic statistical analysis of the shear strength parameters of the sliding zone soil was conducted in conjunction with geotechnical test data, and the Monte Carlo method was used to assess parameter sensitivity. Finally, through spatiotemporal coupling of multi-period InSAR deformation data and numerical simulation results, the dominant structural surface and the spatial morphology of the potential sliding surface were identified, completing the quantitative characterization of the landslide model.

[0134] S102, determine the similarity coefficient of the model test based on similarity theory; in the landslide model test, its basic dimension is mass ,length and time ; Select geometry, mechanics and motion as dimensionally independent basic quantities. Based on dimensional analysis, establish similarity relationships among physical quantities:

[0135] Geometric parameters:

[0136] ;

[0137] Where, is the geometric scale factor between the model and the prototype, is the prototype characteristic length, is the model characteristic length;

[0138] Mechanical parameters, elastic modulus similarity ratio is:

[0139] ;

[0140] Where, is the proportional coefficient of elastic modulus between the model and the prototype, is the stress proportionality coefficient between the model and the prototype;

[0141] The similarity ratio of permeability coefficient is:

[0142] ;

[0143] Where, is the proportional coefficient between the model and prototype permeability coefficients, is the time ratio coefficient between the model and the prototype;

[0144] Dynamic parameters, acceleration similarity ratio:

[0145] ;

[0146] Where, is the acceleration proportional coefficient between the model and the prototype;

[0147] Speed similarity ratio:

[0148] ;

[0149] Where, is the speed ratio coefficient between the model and the prototype;

[0150] Displacement:

[0151] ;

[0152] Where, is the displacement proportional coefficient between the model and the prototype.

[0153] S2, similar material formulation design;

[0154] The mix design scheme is based on the technical features of designing mix proportions based on the principles of materials science. When designing the mix proportions, the mechanical similarity ratio in similarity theory is used as a constraint, and the orthogonal experimental method is used to optimize the composite ratios of aggregate (quartz sand / barite powder to adjust density), gelling agent (gypsum / cement to adjust c value) and toughening phase (fiber / polymer to control brittleness). The porosity and permeability are balanced by controlling the water-cement ratio (0.3-0.45) and the grading curve. Finally, triaxial shear and creep tests are performed to verify the strain hardening, shear dilatancy and long-term stability of the model material, ensuring that its stress-strain curve is consistent with the prototype rock and soil at the normalized scale, thereby achieving cross-scale equivalent simulation of geomechanical behavior.

[0155] The material properties can be fully verified through systematic triaxial shear and creep tests combined with the following steps:

[0156] Strain hardening: confirmed by the monotonically increasing nature of the stress-strain curve;

[0157] Dilatancy: quantified by the positive and negative volumetric strain and dilatancy angle calculation;

[0158] Long-term stability: assessed by the duration of the steady-state phase of the creep curve and the absence of accelerated failure;

[0159] Ultimately, the matching degree between the experimental data and the theoretical model will verify the reliability of the material model.

[0160] S3, testing the physical and mechanical properties of materials;

[0161] Use advanced equipment and methods to test the physical and mechanical properties of materials;

[0162] S301, physical properties testing;

[0163] Density and porosity, wet density determined by the knife ring method , combined with the drying method to calculate the porosity , is the dry density, is the particle density, and the pore distribution of heterogeneous materials is corrected by the improved fractal pore model, which is expressed as:

[0164] ;

[0165] Where, is the corrected effective porosity, is the initial porosity calculated by traditional method, are the maximum and minimum pore diameters, is the pore fractal dimension, which was calibrated by the SEM image box counting method;

[0166] Permeability coefficient, based on variable head permeability test data, introduces non-Darcy flow correction factor :

[0167] ;

[0168] Where, is the corrected permeability coefficient, is the experimentally measured permeability coefficient, is the hydraulic gradient, is the critical gradient;

[0169] S302, mechanical properties testing;

[0170] Shear strength parameters, cohesion obtained by direct shear test or triaxial test and internal friction angle ,Combined with the nonlinear intensity envelope model to optimize the similarity ratio, the expression is:

[0171] ;

[0172] Where, is the cohesion similarity ratio, is the density similarity ratio, is the stress level correction factor, is the normal stress, is the reference stress, is the geometric scale factor between the model and the prototype;

[0173] The deformation modulus is characterized by the strain hardening effect using the triaxial test stress-strain curve and piecewise power function fitting, and the expression is:

[0174] ;

[0175] Where, is the initial modulus, is the critical strain, is the hardening index, is the deformation modulus, For strain.

[0176] S4, based on similarity theory and landslide dynamics principles, use mathematical and numerical methods to calculate the expected speed, acceleration distance and parking height;

[0177] Based on similarity theory and landslide dynamics principles, mathematical and numerical methods are used to accurately calculate the expected speed, acceleration distance, and parking height. Through iteration and error analysis, the results are guaranteed to be accurate and reliable. Specifically, the following are included:

[0178] S401, Dynamic modeling and similarity law correction;

[0179] Assuming that the sliding body is subject to gravity, base friction and internal shear resistance, its motion equation is:

[0180] ;

[0181] Where, is the mass of the landslide, is the landslide velocity, For time, is the acceleration due to gravity, is the sliding surface contact area, is the inclination angle of the material box, is the base friction coefficient, is the shear strength of sliding zone soil, ; For cohesion, is the internal friction angle;

[0182] Similarity scaling: According to Froude's similarity criterion The prototype parameter (subscript ) is converted into model parameters (subscript ):

[0183] ;

[0184] ;

[0185] ;

[0186] Where, is the speed in the model experiment, is the actual velocity of the prototype landslide, is the acceleration in the model experiment, is the actual acceleration of the prototype landslide, is the shear strength of the model material, is the shear strength of the model landslide;

[0187] S402, numerical solution and acceleration distance calculation;

[0188] The improved Runge-Kutta method (RK4) discretizes the equation of motion into:

[0189] ;

[0190] The fourth-order Runge-Kutta method is used to iteratively solve the velocity and displacement:

[0191] ;

[0192] ;

[0193] ;

[0194] ;

[0195] ;

[0196] ;

[0197] Where, are the slopes of the Runge-Kutta method, For the The speed of the time step, For the The displacement of the time step, is the time step, For the The speed of the time step, For the The time point of the time step, For the The displacement of the time step;

[0198] The acceleration distance is defined as the time when the speed reaches a stable value Displacement , by monitoring the speed change rate , determine convergence;

[0199] S403, parking height calculation and energy conservation correction;

[0200] Energy balance equation, the sliding body from the initial height Slide to parking height , the mechanical energy loss is friction work:

[0201] ;

[0202] Where, is the total sliding distance of the landslide from the beginning of sliding to complete stop, is the displacement variable on the sliding path;

[0203] Numerical integration is used to discretize the sliding path into Segment, displacement increment for each segment , iterative calculation of parking height:

[0204] ;

[0205] Where, For the The parking height calculated by the iteration is For the The friction coefficient on the sliding path, For the Shear strength over the sliding distance, For the Displacement increment over the sliding distance;

[0206] Introducing speed-dependent friction coefficient , enhance the nonlinear characterization capability of the model, is the rate effect coefficient, is the basic friction coefficient, is the instantaneous velocity of the landslide.

[0207] S5: Determine the type, quantity, and location of sensors based on the characteristics of landslide movement and observation requirements, monitor and record changes in landslide movement parameters, and form a complete monitoring network;

[0208] Displacement monitoring uses a laser displacement meter (accuracy ±0.01mm) and a high-frequency InSAR (sampling rate 50 ), covering the key points on the sliding surface, and the layout density follows the Nyquist theorem (spacing ≤ sliding wavelength / 2).

[0209] Acceleration acquisition, three-axis MEMS accelerometer (range ±50g, bandwidth 1 ) are embedded in the sliding body and arranged in a hexahedral grid, with the node spacing determined by the sliding body thickness. Decide( ).

[0210] Strain field capture, distributed optical fiber sensing (BOTDR) is laid along the sliding belt, with a spatial resolution of 1m and a strain sensitivity of ±10 .

[0211] S6, material box angle adjustment, adjust the material box rotation angle according to the similarity coefficient and the prototype tilt angle;

[0212] Pay attention to the influence of small changes, repeatedly check and fine-tune, and keep close to the actual tilt state. By controlling the elongation of the flip cylinder 5, the tilt angle of the tilt truss is controlled, and then the tilt angle of the landslide material is controlled; therefore, the initial elongation of the flip cylinder 5, the distance from the flip cylinder 5 to the flip support seat, and the distance from the intersection of the flip support seat and the tilt truss to the intersection of the flip cylinder 5 and the tilt truss are regarded as a triangle; let the initial length of the flip cylinder 5 be The corresponding initial angle is , the distance from the top of the flip cylinder 5 to the flip support seat is The distance from the intersection of the flip support seat and the tilt truss to the intersection of the flip cylinder 5 and the tilt truss is ; Assume that the inclination angle of the prototype landslide is , when the triangle angle is arrive When the hydraulic jack extends .Establish and Function expression of ;

[0213] By the law of cosines:

[0214] ;

[0215] When the side becomes After that, the corresponding angle satisfy:

[0216] ;

[0217] Subtract these two equations:

[0218] ;

[0219] Arranged:

[0220] ;

[0221] S7, conduct landslide model test and material box cleaning and maintenance;

[0222] The landslide model test includes: after preparation, testing according to the plan, using high-speed cameras, data acquisition systems, etc. to observe and record the entire process of landslide movement, record abnormalities, and ensure that the data is complete and accurate.

[0223] Material box cleaning and maintenance include: cleaning the material box in time after the test, removing residual materials, checking and maintaining structures and components, and ensuring the next test conditions and stable operation of the device.

[0224] The above description is only a preferred specific implementation method of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with this technical field within the technical scope disclosed by the present invention and within the spirit and principles of the present invention should be covered by the scope of protection of the present invention.

Claims

1. A test method for a hydraulically driven coal mine landslide speed control device, characterized in that: The method comprises the following steps: S1, prototype analysis and similarity coefficient determination; S2, similar material formulation design; S3, testing the physical and mechanical properties of materials; S4, based on similarity theory and landslide dynamics principles, use mathematical and numerical methods to calculate the expected speed, acceleration distance and parking height; S5: Determine the type, quantity, and location of sensors based on the characteristics of landslide movement and observation requirements, monitor and record changes in landslide movement parameters, and form a complete monitoring network; S6, material box angle adjustment, adjust the material box rotation angle according to the similarity coefficient and the prototype tilt angle; S7, conduct landslide model test and material box cleaning and maintenance; In step S3, the physical and mechanical properties of the material are detected, including: S301, physical properties testing; Density and porosity, wet density determined by the knife ring method , combined with the drying method to calculate the porosity , is the dry density, is the particle density, and the pore distribution of heterogeneous materials is corrected by the improved fractal pore model, which is expressed as: ； Where, is the corrected effective porosity, is the initial porosity calculated by traditional method, are the maximum and minimum pore diameters, is the pore fractal dimension, which was calibrated by the SEM image box counting method; Permeability coefficient, based on variable head permeability test data, introduces non-Darcy flow correction factor : ； Where, is the corrected permeability coefficient, is the experimentally measured permeability coefficient, is the hydraulic gradient, is the critical gradient; S302, mechanical properties testing; Shear strength parameters, cohesion obtained by direct shear test or triaxial test and internal friction angle ,Combined with the nonlinear intensity envelope model to optimize the similarity ratio, the expression is: ； Where, is the cohesion similarity ratio, is the density similarity ratio, is the stress level correction factor, is the normal stress, is the reference stress, is the geometric scale factor between the model and the prototype; The deformation modulus is characterized by the strain hardening effect using the triaxial test stress-strain curve and piecewise power function fitting, and the expression is: ； Where, is the initial modulus, is the critical strain, is the hardening index, is the deformation modulus, For strain; In step S4, the expected speed, acceleration distance, and parking height are calculated using mathematical and numerical methods based on similarity theory and landslide dynamics principles, including: S401, Dynamic modeling and similarity law correction; Assuming that the sliding body is subject to gravity, base friction and internal shear resistance, the motion equation is: ； Where, is the mass of the landslide, is the landslide velocity, For time, is the acceleration due to gravity, is the sliding surface contact area, is the inclination angle of the material box, is the base friction coefficient, is the shear strength of sliding zone soil, ; For cohesion, is the internal friction angle; Similarity Scaling: Convert prototype parameters to model parameters according to the Froude similarity criterion: ； ； ； Where, is the speed in the model experiment, is the actual velocity of the prototype landslide, is the acceleration in the model experiment, is the actual acceleration of the prototype landslide, is the shear strength of the model material, is the shear strength of the model landslide; S402, numerical solution and acceleration distance calculation; The improved Runge-Kutta method discretizes the equation of motion into: ； The fourth-order Runge-Kutta method is used to iteratively solve the velocity and displacement: ； ； ； ； ； ； Where, are the slopes of the Runge-Kutta method, For the The speed of the time step, For the The displacement of the time step, is the time step, For the The speed of the time step, For the The time point of the time step, For the displacement of the time step; The acceleration distance is defined as the time it takes for the speed to reach a stable value. Displacement , by monitoring the speed change rate , determine convergence; S403, parking height calculation and energy conservation correction; Energy balance equation, the sliding body from the initial height Slide to parking height , the mechanical energy loss is friction work: ； Where, is the total sliding distance of the landslide from the beginning of sliding to complete stop, is the displacement variable on the sliding path; Numerical integration is used to discretize the sliding path into Segment, displacement increment for each segment , iterative calculation of parking height: ； Where, For the The parking height calculated by the iteration is For the The friction coefficient on the sliding path, For the Shear strength over the sliding distance, For the Displacement increment over the sliding distance; Introducing speed-dependent friction coefficient , enhance the nonlinear characterization capability of the model, is the rate effect coefficient, is the basic friction coefficient, is the instantaneous velocity of the landslide.

2. The test method of the hydraulic transmission type coal mine landslide speed control device according to claim 1 is characterized in that: In step S1, prototype analysis and similarity coefficient determination include: S101: Analyze the geological conditions of the prototype landslide and complete the quantitative characterization of the landslide model; S102, determine the similarity coefficient of the model test based on similarity theory; in the landslide model test, the basic dimension is mass length and time ; Select geometry, mechanics and motion as dimensionally independent basic quantities, and establish similarity relationships among physical quantities based on dimensional analysis: Geometric parameters: ； Where, is the geometric scale factor between the model and the prototype, is the prototype characteristic length, is the model characteristic length; Mechanical parameters, elastic modulus similarity ratio is: ； Where, is the proportional coefficient of elastic modulus between the model and the prototype, is the stress proportionality coefficient between the model and the prototype; The similarity ratio of permeability coefficient is: ； Where, is the proportional coefficient between the model and prototype permeability coefficients, is the time ratio coefficient between the model and the prototype; Dynamic parameters, acceleration similarity ratio: ； Where, is the acceleration proportional coefficient between the model and the prototype; Speed similarity ratio: ； Where, is the speed ratio coefficient between the model and the prototype; Displacement: ； Where, is the displacement proportional coefficient between the model and the prototype.

3. The test method of the hydraulic transmission type coal mine landslide speed control device according to claim 1, characterized in that: In step S2, similar materials are formulated and designed, including: Constrained by the mechanical similarity ratio in similarity theory, the orthogonal experimental method was used to optimize the composite ratio of aggregate, cementitious agent, and toughening phase, and the porosity and permeability were balanced by controlling the water-cement ratio and gradation curve. Finally, triaxial shear and creep tests were conducted to verify the strain hardening, dilatancy, and long-term stability of the model material, ensuring that the stress-strain curve was consistent with that of the prototype rock and soil at a normalized scale, thus achieving cross-scale equivalent simulation of geomechanical behavior.

4. The test method of the hydraulic transmission type coal mine landslide speed control device according to claim 1, characterized in that: In step S5, the sensor type, quantity and location are determined, including: Displacement monitoring, using laser displacement meters and high-frequency InSAR, covering the sliding surface; Acceleration acquisition, triaxial MEMS accelerometers are embedded in the sliding body and arranged in a hexahedral grid, with the node spacing determined by the thickness of the sliding body. Decide, ; Strain field capture, distributed fiber optic sensing is laid along the sliding belt.

5. The test method of the hydraulic transmission type coal mine landslide speed control device according to claim 1, characterized in that: In step S6, adjusting the rotation angle of the material box includes: The tilt angle of the tilt truss is controlled by controlling the elongation of the flip cylinder fluid, and the tilt angle of the landslide material is controlled; the initial elongation of the flip cylinder, the distance from the flip cylinder to the flip support seat, and the distance from the intersection of the flip support seat and the tilt truss to the intersection of the flip cylinder and the tilt truss are formed into a triangle; the initial length of the flip cylinder is The corresponding initial angle is , the distance from the top of the flip cylinder to the flip support seat is The distance from the intersection of the flip support seat and the tilt truss to the intersection of the flip cylinder and the tilt truss is ; Assume that the inclination angle of the prototype landslide is , when the triangle angle is arrive When the hydraulic jack extends ;Establish and Function expression of ; By the law of cosines: ; When the side becomes After that, the corresponding angle satisfy: ； Subtract these two equations: ； Arranged: 。 6. The test method of the hydraulic transmission type coal mine landslide speed control device according to claim 1, characterized in that: In step S7, a landslide model test and material box cleaning and maintenance are performed, including: using a high-speed camera and a data acquisition system to observe and record the entire landslide movement process and record abnormalities; Material box cleaning and maintenance include: cleaning the material box in time after the test, removing residual materials, and inspecting and maintaining structures and components.

7. A hydraulic transmission type coal mine landslide speed control device, characterized in that: The device implements the test method of the hydraulic transmission type coal mine landslide speed control device according to any one of claims 1 to 6, and the device comprises: a material box (1) for containing landslide material and a tilting truss (4) located below the material box and used to fix the acceleration mechanism, and a tilting cylinder (5) for adjusting the angle of the material box (1); the tilting truss (4) is connected to the base truss (9) through the tilting cylinder (5); a tilting support seat (6) is provided at the front end of the base truss (9); and the tilting cylinder (5) is installed at the rear end of the base truss (9); A high-speed oil cylinder (7), a guide rod (3), and a guide rail (2) are installed in the inclined truss (4), and a power source is provided to the material box 1 through the high-speed oil cylinder (7); A card slot is provided at the bottom of the material box (1), and a buckle (14) is installed at the bottom of the material box (1); the buckle (14) is matched in the card slot; A hydraulic door opening device is installed on the side of the front edge of the material box (1), and the hydraulic door opening device includes a baffle lock (11), a hydraulic rod (10) and a material box door opening device (12); the baffle lock (11) and the hydraulic rod (10) are used in conjunction with each other. When the front edge of the material box (1) is accelerated to the front end of the inclined truss (4), the baffle lock (11) is pulled by the hydraulic rod (10) and rotates upward. The front side baffle of the material box door opening device (12) is pulled by the spring device (13), and the front side baffle of the material box door opening device (12) is opened, releasing the landslide material in the material box (1).

8. The hydraulic transmission type coal mine landslide speed control device according to claim 7, characterized in that: The buckle (14) is engaged with the front of the high-speed oil cylinder (7), and the high-speed oil cylinder (7) provides power to the material box (1), thereby driving the material box (1) to accelerate downward along the longitudinal guide rail (2) through multiple pulleys (8) installed at the bottom of the material box (1), and the buckle (14) is connected to the guide rod (3), and the guide rod (3) is matched in the slot; The flip support seat (6) provided at the front end of the base truss (9) is used as a support point when the tilting truss (4) is flipped, and controls the telescopic length of the flip cylinder (5) provided at the rear end to control the tilting angle of the tilting truss (4), thereby controlling the angle of the material box (1).

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