Method, device and electronic equipment for predicting the influence of rainfall infiltration on slope stability

Abstract

The present invention discloses a method, device and electronic device for predicting the influence of rainfall infiltration on slope stability. The method comprises: constructing a first slope model through water level monitoring data and initial construction values; calculating the gravity and first pore pressure of the actual slope based on the initial construction values, and clearing the initial displacement field of the first slope model to obtain a second slope model; detecting the second pore pressure of the second slope model through a pressure probe, and setting a rainfall infiltration boundary condition on the second slope model based on the second pore pressure; taking the second pore pressure as the external stress of the stress field, and taking the volume strain as the source term of the seepage field for bidirectional coupling; calculating the plastic strain of the second slope model in the rainfall infiltration boundary process based on the initial construction values, and determining that the actual slope is in the first state when the plastic strain calculation no longer converges. The method can more accurately predict the influence of rainfall infiltration on slope stability, and can be applied to the field of predicting the influence of rainfall on slope stability.

Description

Technical Field

[0001] The invention relates to the field of predicting the influence of rainfall infiltration on slope stability, in particular to a method and field of predicting the influence of rainfall infiltration on slope stability. Background Art

[0002] Groundwater is one of the important factors that lead to slope instability, and draining groundwater from the slope is crucial to improving slope stability. However, rainfall or drainage will change the groundwater seepage path, especially in the sudden heavy rainfall season. While the physical and mechanical properties of the slope soil are changed, it will also significantly affect the seepage and deformation characteristics inside the slope, causing the slope that was originally in a mechanical equilibrium state to suddenly become unstable and damaged during rainfall. Therefore, understanding the changes in slope stability under the action of rainfall infiltration is of great guiding significance for the drainage and support design of the slope. Summary of the invention

[0003] In view of this, an embodiment of the present invention provides a method, device and electronic device for predicting the influence of rainfall infiltration on slope stability, so as to more accurately predict the influence of rainfall infiltration on slope stability.

[0004] One aspect of the present invention provides a method for predicting the influence of rainfall infiltration on slope stability, comprising: determining the seepage boundary conditions of a first slope model through water level monitoring data, constructing the first slope model based on the seepage boundary conditions and initial construction values, wherein the water level monitoring data is the water level data of the actual slope monitored, and the initial construction values ​​are the geological data of the actual slope; calculating the gravity and the first pore pressure of the actual slope based on the initial construction values, clearing the initial displacement field of the first slope model to zero based on the gravity of the actual slope and the first pore pressure to obtain a second slope model; detecting the second pore pressure of the second slope model through a pressure probe, and based on the initial construction values, The numerical value of the second pore pressure sets the rainfall infiltration boundary condition on the second slope model; the second pore pressure is used as the external stress of the stress field of the second slope model, and the volume strain is used as the source term of the seepage field of the second slope model to perform bidirectional coupling, wherein the volume strain is the ratio of the volume change of the second slope model during the rainfall infiltration boundary treatment process to the initial volume of the second slope model; the plastic strain of the second slope model during the rainfall infiltration boundary process is calculated based on the cohesion and internal friction angle in the initial construction value, and when the plastic strain calculation no longer converges, it is determined that the second slope model is in the first state, and the actual slope is in the first state.

[0005] According to some embodiments of the present invention, the method of determining the seepage boundary conditions of the first slope model through water level monitoring data and constructing the first slope model based on the seepage boundary conditions and initial construction values ​​includes: meshing the first slope model, wherein the maximum unit size of the grid near the slope surface of the first slope model has the smallest value.

[0006] According to some embodiments of the present invention, the gravity and the first pore pressure of the actual slope are calculated based on the initial construction value, and the initial displacement field of the first slope model is cleared to obtain the second slope model based on the gravity of the actual slope and the first pore pressure, including: obtaining the initial stress field by calculating according to the gravity of the actual slope and the first pore pressure; performing ground stress balance calculation on the first slope model according to the initial stress field, so that the initial displacement field of the first slope model is cleared to obtain the second slope model.

[0007] According to some embodiments of the present invention, the second pore pressure of the second slope model is detected by a pressure probe, and a rainfall infiltration boundary condition is set on the second slope model based on the value of the second pore pressure, including: when the second pore pressure is less than 0, a fixed flow boundary is applied to the slope surface of the second slope model; when the second pore pressure is greater than or equal to 0, a fixed pressure boundary is applied to the slope surface of the second slope model; wherein the calculation formulas of the fixed flow boundary and the fixed pressure boundary are: Where n is the boundary normal vector; ρ f is the water density; u is the seepage velocity; R is the rainfall intensity; A is the conversion function; L is the infiltration boundary thickness; K s is the saturated permeability coefficient; p is the second pore pressure; g is the gravitational acceleration.

[0008] According to some embodiments of the present invention, before setting the rainfall infiltration boundary condition on the second slope model based on the value of the second pore pressure, the method includes: setting a part of the smooth segment of the transfer function; obtaining the value of the second pore pressure and adjusting the transfer function according to the value of the second pore pressure.

[0009] According to some embodiments of the present invention, the second pore pressure is used as the external stress of the stress field of the second slope model, and the volume strain is used as the source term of the seepage field of the second slope model for bidirectional coupling. In this step, the calculation formula for using the second pore pressure as the external stress of the stress field of the second slope model is: Where, σ is stress; S e is the effective saturation; p is the second pore pressure; ρ f is the density of water; θ s is the saturated water content; ρs is the density of the soil; g is the acceleration due to gravity.

[0010] According to some embodiments of the present invention, the second pore pressure is used as the external stress of the stress field of the second slope model, and the volume strain is used as the source term of the seepage field of the second slope model for bidirectional coupling. In this step, the calculation formula for using the volume strain as the source term of the seepage field of the second slope model is: Among them, ρ f is the density of water, C m is the water content; g is the gravitational acceleration; S e is the effective saturation; S is the water storage coefficient; p is the second pore pressure; t is the time; K s is the saturated permeability coefficient; κ r is the relative permeability; D is the elevation; ε v is the volumetric strain.

[0011] According to some embodiments of the present invention, when the plastic strain calculation no longer converges, it is determined that the second slope model is in the first state, and after the step of the actual slope being in the first state, it includes: obtaining the transient calculation result of the seepage stress when the second slope model is in the first state; continuously adjusting the strength index and reduction factor of the slope based on the transient calculation result of the seepage stress until the second slope model is in a critical failure state, and obtaining the current reduction factor as a safety factor.

[0012] One aspect of the present invention provides a device for predicting the influence of rainfall infiltration on slope stability, comprising: a first module, used to determine the seepage boundary conditions of a first slope model through water level monitoring data, and to construct the first slope model based on the seepage boundary conditions and initial construction values, wherein the water level monitoring data is the monitored water level data of the actual slope, and the initial construction value is the geological data of the actual slope; a second module, used to calculate the gravity and the first pore pressure of the actual slope based on the initial construction value, and to clear the initial displacement field of the first slope model to obtain a second slope model based on the gravity of the actual slope and the first pore pressure; and a third module, used to detect the second pore pressure of the second slope model through a pressure probe. A rainfall infiltration boundary condition is set on the second slope model based on the value of the second pore pressure; a fourth module is used to use the second pore pressure as the external stress of the stress field of the second slope model and the volume strain as the source term of the seepage field of the second slope model for bidirectional coupling, wherein the volume strain is the ratio of the volume change of the second slope model during the rainfall infiltration boundary processing to the initial volume of the second slope model; a fifth module is used to calculate the plastic strain of the second slope model during the rainfall infiltration boundary process based on the cohesion and internal friction angle in the initial construction value, and when the plastic strain calculation no longer converges, it is determined that the second slope model is in the first state, and the actual slope is determined to be in the first state.

[0013] Another aspect of the present invention provides an electronic device, including a processor and a memory; the memory is used to store a program; the processor executes the program to implement a method for predicting the impact of rainfall infiltration on slope stability.

[0014] The electronic device according to the embodiment of the present invention has at least the same beneficial effect as the above-mentioned method for predicting the influence of rainfall infiltration on slope stability.

[0015] The embodiment of the present invention also discloses a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. A processor of a computer device can read the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the above method.

[0016] The embodiment of the present invention constructs a first slope model and seepage boundary conditions by acquiring geological data and water level data of the actual slope, and calculates gravity based on the density of the geological data of the actual slope, and calculates the first pore pressure based on the water level data. The initial displacement field of the first slope model is cleared by gravity and the first pore pressure to obtain a second slope model. By clearing the initial displacement field, the second slope model is more consistent with the actual slope, thereby improving the accuracy of subsequent predictions. The initial second pore pressure of the second slope model is detected by a pressure probe, and the rainfall infiltration boundary conditions are set according to the value of the second pore pressure. This is to realize the automatic conversion of different boundary conditions according to different pore pressure sizes, without the need to manually set different boundary conditions according to rainfall data. The operation is simple and convenient, and the simulation efficiency can also be improved. By taking the second pore pressure as the external stress of the stress field of the second slope model and the volume strain as the source term of the seepage field of the second slope model, the seepage field and the stress field are bidirectionally coupled, and the plastic strain of the second slope model in the rainfall infiltration boundary process is calculated based on the cohesion and internal friction angle in the initial construction value. When the plastic strain calculation no longer converges, it is determined that the second slope model is in the first state. Because the second slope model simulates the actual slope, it also indicates that the actual slope will be in the first state when the rainfall reaches the simulated rainfall infiltration treatment. By constructing a second slope model consistent with the actual slope and subjecting the second slope model to rainfall, during the rainfall process, the pressure probe is used to realize the automatic conversion of the rainfall infiltration boundary conditions to improve the simulation efficiency, and the bidirectional coupling is used to make the calculation results more accurate and consistent with the actual slope engineering, thereby predicting the impact of rainfall on the stability of the actual slope. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 A flowchart of the steps of a method for predicting the influence of rainfall infiltration on slope stability provided by an embodiment of the present invention;

[0019] Figure 2 Schematic diagram of geometric model and boundary conditions provided for embodiments of the present invention

[0020] Figure 3 A schematic diagram of mesh generation of a first slope model provided by an embodiment of the present invention;

[0021] Figure 4A distribution diagram of initial stress and initial displacement of a first slope model provided by an embodiment of the present invention;

[0022] Figure 5 A schematic diagram of the relationship between the conversion function A and the pressure p provided in an embodiment of the present invention;

[0023] Figure 6 The saturation and seepage field distribution diagram of the second slope model before and after rainfall provided by the embodiment of the present invention;

[0024] Figure 7 A plastic strain distribution diagram of the second slope model before and after rainfall provided by an embodiment of the present invention;

[0025] Figure 8 A schematic diagram of a slope sliding surface of a second slope model provided in an embodiment of the present invention;

[0026] Fig. 9 A safety factor variation curve of the second slope model at different rainfall moments provided by an embodiment of the present invention;

[0027] Fig.10 A schematic block diagram of a device for predicting the impact of rainfall infiltration on slope stability provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0029] Rainfall or drainage will change the seepage path of groundwater, resulting in a significant coupling effect between the seepage field and the stress field in the slope, especially in the heavy rainfall season. Under the action of rainfall infiltration and multi-field coupling environment, the physical and mechanical properties of the slope soil are changed, and the seepage and deformation characteristics inside the slope are significantly affected, resulting in the slope that was originally in a mechanical equilibrium state suddenly becoming unstable and damaged during rainfall. At present, numerical simulation is widely used to understand the impact of rainfall infiltration on slope stability. At that time, the commonly used method required the calculation of the seepage field first, and then the pressure field at different times was introduced into the slope stability calculation to evaluate the impact of rainfall infiltration on slope stability. The process was not only cumbersome and complicated, but also only considered the one-way coupling of the seepage field to the stress field, which was inconsistent with the actual on-site engineering. Therefore, how to establish a slope model that considers the bidirectional coupling effect of seepage stress to accurately predict the impact of rainfall infiltration on slope stability is a technical problem that needs to be solved urgently. Therefore, the present application proposes a method, device and electronic device for predicting the impact of rainfall infiltration on slope stability to more accurately predict the impact of rainfall infiltration on slope stability.

[0030] refer to Figure 1 , Figure 1 The flowchart of the method for predicting the influence of rainfall infiltration on slope stability provided by the embodiment of the present invention includes steps S100 to S600:

[0031] Step S100, determining the seepage boundary conditions of the first slope model through water level monitoring data, and constructing the first slope model based on the seepage boundary conditions and initial construction values, wherein the water level monitoring data is the monitored water level data of the actual slope, and the initial construction value is the geological data of the actual slope.

[0032] Specifically, relevant data of the actual slope, such as water level monitoring data and geological data, are obtained through geological background information, field investigations, etc. The pressure head of the actual slope on the boundary is determined based on the water level monitoring data, that is, the seepage boundary conditions are obtained. A first slope model is constructed based on the seepage boundary conditions and the initial construction values, wherein the first slope model can be established through software, such as COMSOL Multiphysics software, and the first slope model is meshed, and a typical profile is usually selected for modeling. It should be noted that since the slope is affected by rainfall infiltration, it is necessary to encrypt the mesh near the slope to improve the convergence of the calculation. After encryption, the maximum unit size of the mesh near the slope is minimized. For example, the maximum unit size of the mesh near the slope is set to 0.5m, and the maximum unit size of the remaining mesh is set to 5m. In addition, the initial construction values ​​include but are not limited to physical and mechanical parameters and model parameters. The physical and mechanical parameters of the actual slope include but are not limited to: the density ρ of the soil s , elastic modulus E, Poisson's ratio ν, cohesion c and internal friction angle Van Genuchten model parameters include but are not limited to: saturated permeability coefficient K of soil s , water storage coefficient S, saturated water content θ s , residual moisture contentθ r , constitutive relationship constants α, n and l.

[0033] Step S200, calculating the actual slope gravity and the first pore pressure based on the initial construction value, and clearing the initial displacement field of the first slope model based on the actual slope gravity and the first pore pressure to obtain the second slope model.

[0034] Specifically, the actual slope gravity can be obtained through the soil density, gravitational acceleration, and height in the initial construction value, and the first pore pressure can be obtained according to the seepage boundary. Then, the initial stress field of the slope under the action of gravity and the first pore pressure is calculated, and it is input as an internal force into the ground stress balance calculation, and the initial displacement field is cleared to obtain the second slope model. Exemplarily, the initial stress field of the slope under the action of gravity and pore pressure is calculated, and then the initial stress field is input as an internal force into the ground stress balance calculation through the "Prestress and Prestrain" interface in the COMSOL Multiphysics software, and the initial displacement field is cleared.

[0035] Step S300: detecting a second pore pressure of a second slope model by means of a pressure probe, and setting a rainfall infiltration boundary condition on the second slope model based on the value of the second pore pressure.

[0036] Specifically, the second pore pressure of the second slope model is detected by a pressure probe. For example, the "probe" in the COMSOL Multiphysics software can be used to monitor the pore pressure of the second slope model in real time. It can be understood that at this time, the second pore pressure detected by the pressure probe is the initial pore pressure value of the second slope model. When the second pore pressure is less than 0, a fixed flow boundary is applied to the slope surface of the second slope model; when the second pore pressure is greater than or equal to 0, a fixed pressure boundary is applied to the slope surface of the second slope model; wherein, the calculation formulas for the fixed flow boundary and the fixed pressure boundary are: Where n is the boundary normal vector; ρ f is the water density; u is the seepage velocity; R is the rainfall intensity; A is the conversion function; L is the infiltration boundary thickness; K s is the saturated permeability coefficient; p is the second pore pressure; g is the gravitational acceleration. It can be seen that when the second pore pressure is less than 0, the rainfall infiltration boundary condition applied to the slope of the second slope model becomes a fixed flow boundary, and the flow size is equal to the rainfall intensity, expressed as -n·ρ f u=ρ f R; When the second pore pressure is greater than or equal to 0, the rainfall infiltration boundary condition applied to the slope surface of the second slope model becomes a fixed pressure boundary, and its expression is: It should be noted that when the second slope model is subjected to rainfall infiltration boundary processing, the detected second pore pressure will continuously change due to rainfall infiltration. Therefore, the boundary conditions selected and applied based on the second pore pressure are also continuously converted. Thus, the automatic conversion of fixed flow boundary and fixed pressure boundary conditions is realized by using a pressure probe. Furthermore, a rainfall infiltration boundary condition is set on the slope surface of the second slope model. In order to prevent the sudden change of the value from causing the calculation result to not converge, a part of the smooth segment is set for the conversion function, and then the size of the second pore pressure is obtained, and the conversion function is further selected according to the interval of the second pore pressure.

[0037] Step S400: taking the second pore pressure as the external stress of the stress field of the second slope model and taking the volume strain as the source term of the seepage field of the second slope model, and performing bidirectional coupling.

[0038] Specifically, the second pore pressure is input as an external stress into the stress field of the second slope model, and the volume strain is input as a source term into the seepage field of the second slope model. The calculation formula for using the second pore pressure as the external stress of the stress field of the second slope model is: Where, σ is stress; S e is the effective saturation; p is the second pore pressure; ρ f is the density of water; θ s is the saturated water content; ρ s is the density of the soil; g is the gravitational acceleration. The calculation formula for the seepage field using volumetric strain as the source term of the second slope model is: Among them, ρ f is the density of water, C m is the water content; g is the gravitational acceleration; S e is the effective saturation; S is the water storage coefficient; p is the second pore pressure; t is the time; K s is the saturated permeability coefficient; κ r is the relative permeability; D is the elevation; ε v is the volume strain. Thus, the bidirectional coupling of the seepage field and the stress field is realized, and the calculation results are more accurate and in line with actual engineering.

[0039] Step S500, based on the cohesion and internal friction angle in the initial construction value, the plastic strain of the second slope model during the rainfall infiltration boundary process is calculated, wherein the volume strain is the ratio of the volume change of the second slope model during the rainfall infiltration boundary processing to the initial volume of the second slope model. When the plastic strain calculation no longer converges, it is determined that the second slope model is in the first state, and the actual slope is in the first state.

[0040] Specifically, the plastic strain of the second slope model is calculated using the Mohr-Coulomb yield criterion. The calculation no longer converges, indicating that the second slope model is in the first state, wherein the Mohr-Coulomb yield criterion calculation requires the use of the cohesion and internal friction angle in the initial construction value for calculation. It should be noted that the first state indicates that the second slope model is about to become unstable. Because the second slope model simulates the actual slope, it can be concluded that during the rainfall infiltration boundary treatment process, when the rainfall infiltration reaches a certain critical point, the actual slope will become unstable. Further, according to the saturation and seepage field distribution obtained in the process of bidirectional coupling between the seepage field and the stress field, for example, during heavy rainfall, according to the saturation and seepage field distribution, it can be analyzed that the slope soil gradually changes from an unsaturated state to a saturated state, causing the strength of the slope soil to gradually decrease with the increase in rainfall. After calculating the plastic strain, we further obtain the transient calculation results of the seepage stress corresponding to the moment of instability, and use the strength reduction method to calculate the slope safety factor at different rainfall moments. The specific steps include: obtaining the transient calculation results of the seepage stress when the second slope model is in an unstable state; continuously adjusting the strength index and reduction factor of the slope based on the transient calculation results of the seepage stress until the second slope model is in a critical failure state, and obtaining the current reduction factor as the safety factor. By obtaining the slope coefficient at different rainfall moments, we can analyze the change of the slope safety factor with the change of rainfall, and further predict whether the slope is in an unstable state based on the safety factor.

[0041] This application constructs a second slope model consistent with the actual slope, and uses simulated rainfall on the second slope model to predict the impact of rainfall on stability in the actual slope, and automatically completes the conversion of the slope fixed pressure boundary or fixed flow boundary through the pressure probe, without manually setting two boundary conditions according to rainfall data. It is not only simple and convenient to operate, but also improves simulation efficiency. In addition, by inputting the second pore pressure as an external stress into the stress field, and then inputting the volume strain as a source term into the seepage field, the two-way coupling of the seepage field and the stress field is realized, and the calculation results are more accurate and in line with actual engineering, and the impact of rainfall infiltration on slope stability is predicted more scientifically and accurately.

[0042] The following provides specific embodiments:

[0043] According to the geological background data of the study area, a slope model with a length of 240m, a width of 120m, a height of 110m and an inclination of about 24° was established in COMSOL Multiphysics software. According to the differences in soil parameters, the slope was subdivided into five soil layers, such as Figure 2At the same time, the slope model is meshed. Since the slope surface is affected by rainfall infiltration, the maximum unit size of the grid near the slope surface is set to 0.5m, and the maximum unit size of the grid in the rest of the slope is set to 5m, as shown in Figure 3 As shown, it should be noted that Figure 3 In the table, 0.5m and 5m refer to the cell size of the grid, not the cell area.

[0044] The physical and mechanical parameters of the slope soil and the Van Genuchten model parameters are shown in Tables 1 and 2. Table 1 is a list of model parameter values:

[0045] Table 1

[0046]

[0047] Table 2 shows the parameters of the Van Genuchten model:

[0048] Table 2

[0049]

[0050] According to the hydrogeological background data of the study area, the boundary pressure heads of the slopes before rainfall are 60m and 83m respectively, and the bottom boundary and the left and right side boundaries are water-retaining boundaries, such as Figure 2 As shown;

[0051] Calculate the initial stress field of the slope under the action of gravity and pore pressure, and then input the initial stress field as internal force into the ground stress equilibrium calculation through the "Prestress and Prestrain" interface in COMSOL Multiphysics software, and clear the initial displacement field, such as Figure 4 shown.

[0052] The rainfall infiltration boundary condition is set on the slope surface. In order to prevent the sudden change of the value from causing the calculation result to not converge, a part of the smooth segment is set for the conversion function A, such as Figure 5 In COMSOL Multiphysics software, a boundary probe is set, the slope is selected as the boundary, and the pressure p is selected as the monitoring variable. When the pressure probe detects that p<0, the rainfall infiltration boundary condition becomes a fixed flow boundary, and its expression is -n·ρ f u=ρ f R, the flow rate is equal to the rainfall intensity of 0.04m / h; when the pressure probe monitors p≥0, the rainfall infiltration boundary condition becomes a fixed pressure boundary, and its expression is

[0053] Set up bidirectional coupling between seepage field and stress field, input pore pressure p as external stress into solid mechanics module in COMSOL Multiphysics software, set mass source in Richards equation module, input expression -dl.Se*dl.rho*d(solid.evol,TIME) to realize bidirectional coupling between seepage field and stress field. Mohr-Coulomb yield criterion is used to calculate plastic strain of slope soil during rainfall infiltration, calculation time is set to 5d, time step is set to 0.01d, when the model is calculated to 4.66d, it no longer converges, indicating that the slope is about to become unstable, at this time, the saturation and seepage field distribution of slope model are as follows: Figure 6 As shown in the figure, the arrows indicate the size and direction of seepage. The results show that due to the influence of rainfall infiltration, the seepage field of the slope model has changed. Rainwater continuously infiltrates into the soil from the top of the slope, causing the slope soil to gradually change from an unsaturated state to a saturated state, causing the strength of the slope soil to gradually decrease with the increase in rainfall. The plastic strain distribution of the slope soil is shown in Figure 7 As shown in the figure, the results show that due to the influence of rainfall infiltration, a large plastic strain appeared near the toe of the slope, resulting in the imminent instability of the slope.

[0054] Based on the transient calculation results of seepage stress obtained from the two-way coupling and Mohr-Coulomb yield criterion calculation, the auxiliary scanning function in COMSOL Multiphysics software can be used to easily realize the reduction calculation of the slope safety factor. The scanning range of the safety factor is set to range(0.8,0.01,2). The calculated slope sliding surface is as follows: Figure 8 Before rainfall, the safety factor of the slope was 1.67, and the safety factor changes at different rainfall times are shown in Fig. 9 The results show that with the increase of rainfall time, the slope safety factor gradually decreases. When the rainfall time is 4.66 days, the slope safety factor decreases to 1.01, indicating that the slope is about to become unstable.

[0055] If only the one-way coupling of the seepage field and the stress field is considered, that is, the mass source term in the Richards equation is ignored, the safety factor of the slope after rainfall is calculated to be 1.06. The closer the safety factor is to 1, the easier it is for the slope to become unstable. Therefore, the present invention not only realizes the two-way coupling of the seepage field and the stress field and the automatic conversion of the rainfall infiltration boundary, but also can more accurately calculate the safety factor of the slope, thereby guiding the drainage and support design of the slope. At the same time, COMSOL Multiphysics software is easy to operate and has high calculation efficiency. This method has practical significance and value in the study of this problem in the geotechnical field.

[0056] The above is only the preferred implementation of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application. The software used is only the preferred software, and other software with similar functions may be used in other embodiments.

[0057] On the one hand, referring to Fig.10 This embodiment also provides a device for predicting the impact of rainfall infiltration on slope stability, which at least includes: a first module 1010, a second module 1020, a third module 1030, a fourth module 1040, and a fifth module 1050.

[0058] Specifically, the first module 1010 is used to determine the seepage boundary conditions of the first slope model through water level monitoring data, and to construct the first slope model based on the seepage boundary conditions and the initial construction values. The second module 1020 is connected to the first module 1010, and obtains the first slope model in the first module 1010, calculates the gravity and the first pore pressure according to the initial construction values, and clears the initial displacement field of the first slope model to obtain the second slope model; the third module 1030 is connected to the second module 1020, and obtains the second slope model in the second module 1020, and detects the second pore pressure of the second slope model with a pressure probe, and sets the rainfall infiltration boundary conditions on the second slope model based on the value of the second pore pressure. Boundary conditions; the fourth module 1040 is connected to the third module 1030, and the second slope model for rainfall infiltration boundary treatment in the third module 1030 is obtained, and the second pore pressure is used as the external stress of the stress field of the second slope model, and the volume stress is used as the source term of the seepage field of the second slope model to perform bidirectional coupling; the fifth module 1050 is connected to the fourth module 1040, and the second slope model in the fourth module 1040 is obtained. The plastic strain of the second slope model in the process of rainfall infiltration boundary treatment is calculated based on the cohesion and internal friction angle of the initial construction value. When the plastic strain calculation no longer converges, it is determined that the second slope model is in the first state, and the actual slope is in the first state.

[0059] The embodiment of the present invention also discloses a computer program product or a computer program, wherein the computer program product or the computer program includes a computer instruction, and the computer instruction is stored in a computer-readable storage medium. A processor of a computer device can read the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes Figure 1 The method shown.

[0060] In some selectable embodiments, the function / operation mentioned in the block diagram may not occur in the order mentioned in the operation diagram. For example, depending on the function / operation involved, the two boxes shown in succession can actually be executed substantially simultaneously or the boxes can sometimes be executed in reverse order. In addition, the embodiment presented and described in the flow chart of the present invention is provided by way of example, for the purpose of providing a more comprehensive understanding of technology. The disclosed method is not limited to the operation and logic flow presented herein. Selectable embodiments are expected, wherein the order of various operations is changed and the sub-operation of a part for which is described as a larger operation is performed independently.

[0061] In addition, although the present invention is described in the context of functional modules, it should be understood that, unless otherwise specified, one or more of the functions and / or features described may be integrated into a single physical device and / or software module, or one or more functions and / or features may be implemented in separate physical devices or software modules. It is also understood that a detailed discussion of the actual implementation of each module is unnecessary for understanding the present invention. More specifically, in view of the properties, functions, and internal relationships of the various functional modules in the device disclosed herein, the actual implementation of the module will be understood within the conventional skills of the engineer. Therefore, those skilled in the art can implement the present invention set forth in the claims without excessive experimentation using ordinary techniques. It is also understood that the specific concepts disclosed are merely illustrative and are not intended to limit the scope of the present invention, which is determined by the full scope of the appended claims and their equivalents.

[0062] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0063] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0064] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0065] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0066] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0067] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

[0068] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the described embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A method for predicting the effect of rainfall infiltration on slope stability, characterized in that: include: Determine the seepage boundary conditions of the first slope model through water level monitoring data, and construct the first slope model based on the seepage boundary conditions and initial construction values, wherein the water level monitoring data is the monitored water level data of the actual slope, and the initial construction value is the geological data of the actual slope; Calculating the actual slope gravity and the first pore pressure based on the initial construction value, and clearing the initial displacement field of the first slope model to obtain the second slope model based on the actual slope gravity and the first pore pressure; detecting a second pore pressure of the second slope model by a pressure probe, and setting a rainfall infiltration boundary condition on the second slope model based on a value of the second pore pressure; The second pore pressure is used as the external stress of the stress field of the second slope model, and the volume strain is used as the source term of the seepage field of the second slope model to perform bidirectional coupling, wherein the volume strain is the ratio of the volume change of the second slope model during the rainfall infiltration boundary treatment process to the initial volume of the second slope model; The plastic strain of the second slope model during the rainfall infiltration boundary process is calculated based on the cohesion and the internal friction angle in the initial construction value. When the plastic strain calculation no longer converges, it is determined that the second slope model is in the first state, and it is determined that the actual slope is in the first state.

2. A method for predicting the impact of rainfall infiltration on slope stability according to claim 1, characterized in that: The method of determining the seepage boundary condition of the first slope model through water level monitoring data and constructing the first slope model based on the seepage boundary condition and the initial construction value includes: The first slope model is meshed, wherein the value of the maximum unit size of the mesh near the slope surface of the first slope model is the smallest.

3. A method for predicting the impact of rainfall infiltration on slope stability according to claim 1, characterized in that: The step of calculating the actual slope gravity and the first pore pressure based on the initial construction value, and clearing the initial displacement field of the first slope model to obtain the second slope model based on the actual slope gravity and the first pore pressure, comprises: Calculating an initial stress field according to the gravity of the actual slope and the first pore pressure; A geostress balance calculation is performed on the first slope model according to the initial stress field, so that the initial displacement field of the first slope model is reset to zero to obtain a second slope model.

4. A method for predicting the effect of rainfall infiltration on slope stability according to claim 1, characterized in that: The step of detecting the second pore pressure of the second slope model by a pressure probe and setting a rainfall infiltration boundary condition on the second slope model based on the value of the second pore pressure includes: When the second pore pressure is less than 0, applying a fixed flow boundary on the slope surface of the second slope model; When the second pore pressure is greater than or equal to 0, applying a fixed pressure boundary on the slope surface of the second slope model; The calculation formulas for the fixed flow boundary and the fixed pressure boundary are as follows: Where n is the boundary normal vector; ρ f is the water density; u is the seepage velocity; R is the rainfall intensity; A is the conversion function; L is the infiltration boundary thickness; K s is the saturated permeability coefficient; p is the second pore pressure; g is the gravitational acceleration.

5. A method for predicting the effect of rainfall infiltration on slope stability according to claim 4, characterized in that: Before setting the rainfall infiltration boundary condition on the second slope model based on the value of the second pore pressure, the method includes: Set the conversion function to a part of the smooth segment; The value of the second pore pressure is obtained and the transfer function is adjusted according to the value of the second pore pressure.

6. A method for predicting the effect of rainfall infiltration on slope stability according to claim 1, characterized in that: The second pore pressure is used as the external stress of the stress field of the second slope model, and the volume strain is used as the source term of the seepage field of the second slope model to perform bidirectional coupling. In this step, The calculation formula of the second pore pressure as the external stress of the stress field of the second slope model is: Where, σ is stress; S e is the effective saturation; p is the second pore pressure; ρ f is the density of water; θ s is the saturated water content; ρ s is the density of the soil; g is the acceleration due to gravity.

7. A method for predicting the effect of rainfall infiltration on slope stability according to claim 1, characterized in that: The second pore pressure is used as the external stress of the stress field of the second slope model, and the volume strain is used as the source term of the seepage field of the second slope model to perform bidirectional coupling. In this step, The calculation formula for the seepage field of the second slope model using volumetric strain as the source term is: Among them, ρ f is the density of water, C m is the water content; g is the gravitational acceleration; S e is the effective saturation; S is the water storage coefficient; p is the second pore pressure; t is the time; K s is the saturated permeability coefficient; κ r is the relative permeability; D is the elevation; ε v is the volumetric strain.

8. The method for predicting the effect of rainfall infiltration on slope stability according to claim 1, characterized in that: After the step of determining that the second slope model is in the first state when the plastic strain calculation no longer converges, and the actual slope is in the first state, the method further comprises: Obtaining transient calculation results of seepage stress when the second slope model is in a first state; The strength index and reduction factor of the slope are continuously adjusted based on the transient calculation result of the seepage stress until the second slope model is in a critical failure state, and the current reduction factor is obtained as a safety factor.

9. A device for predicting the effect of rainfall infiltration on slope stability, characterized in that: include: A first module is used to determine the seepage boundary conditions of the first slope model through water level monitoring data, and to construct the first slope model based on the seepage boundary conditions and initial construction values, wherein the water level monitoring data is the monitored water level data of the actual slope, and the initial construction value is the geological data of the actual slope; A second module is used to calculate the gravity and the first pore pressure of the actual slope based on the initial construction value, and to clear the initial displacement field of the first slope model to obtain a second slope model based on the gravity and the first pore pressure of the actual slope; A third module is used to detect a second pore pressure of the second slope model by a pressure probe, and to set a rainfall infiltration boundary condition on the second slope model based on a value of the second pore pressure; The fourth module is used to use the second pore pressure as the external stress of the stress field of the second slope model and the volume strain as the source term of the seepage field of the second slope model for bidirectional coupling, wherein the volume strain is the ratio of the volume change of the second slope model during the rainfall infiltration boundary processing to the initial volume of the second slope model; The fifth module is used to calculate the plastic strain of the second slope model during the rainfall infiltration boundary process based on the cohesion and internal friction angle in the initial construction value. When the plastic strain calculation no longer converges, it is determined that the second slope model is in the first state, and it is determined that the actual slope is in the first state.

10. An electronic device, characterized in that: including a processor and a memory; The memory is used to store programs; The processor executes the program to implement the method according to any one of claims 1 to 8.

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