Slope stability analysis and dynamic feedback method based on heavy rainfall condition

Abstract

The invention discloses a slope stability analysis and dynamic feedback method based on a heavy rainfall condition. Comprising the steps that a heterogeneous slope model is constructed in a computer system, units are divided, and lithologic partition parameters are determined; deducing the displacement direction of the infiltration line, determining the maximum range of the infiltration line, and generating a heterogeneous slope longitudinal section thermodynamic diagram of different rainfall durations; establishing a bidirectional coupling model of an unsaturated-saturated seepage field and a stress field, tracking infiltration line displacement and plastic strain zone expansion, and calculating the evolution of a safety coefficient along with rainfall duration; when the safety coefficient reaches a set threshold value, potential sliding surface displacement increment is monitored, residual speed is calculated, and a residual speed sequence changing along with rainfall duration under the same safety coefficient is formed and marked on the longitudinal section thermodynamic diagram; and identifying a sliding risk area in combination with the residual speed sequence, designing a drainage optimization scheme and dynamically adjusting parameters. The effectiveness of slope drainage prevention and control under the heavy rainfall condition is remarkably improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of geotechnical engineering or geotechnical engineering, in particular to the analysis and dynamic feedback regulation technology of slope stability under heavy rainfall conditions. BACKGROUND

[0002] Under heavy rainfall conditions, the risk of slope instability increases significantly, and accurate analysis of slope stability and timely feedback adjustment of control measures are crucial to engineering safety. Existing slope stability analysis methods are mostly based on the assumption of homogeneous slope, which fails to fully consider the heterogeneous characteristics such as fissures and weak interlayers formed by geological structure in actual slopes, resulting in a large deviation between the constructed model and the actual geological conditions, and making it difficult to accurately reflect the spatial differences of hydrogeological parameters within the slope, affecting the accuracy of stability evaluation.

[0003] In traditional slope stability analysis, there are limitations in the coupling analysis of seepage field and stress field. Most methods do not adequately consider the nonlinear relationship between matric suction and water content in the unsaturated zone, fail to dynamically track the movement path of the wetting front and the evolution of the saturated zone boundary during the rainfall process, and do not describe the attenuation law of rock and soil strength parameters (such as cohesion and internal friction angle) with water content in detail, resulting in that the safety factor calculation results are difficult to truly reflect the dynamic influence of rainfall duration on slope stability, and prone to evaluation lag or misjudgment.

[0004] In addition, the existing technology has deficiencies in dynamic feedback and risk control. On the one hand, there is a lack of mechanism to effectively integrate real-time monitoring data (such as slope displacement increment) with numerical simulation results, making it difficult to accurately identify the area of sliding risk; on the other hand, the design of drainage optimization scheme relies heavily on experience, and fails to combine detailed analysis results such as the distribution of wetting front, pore water pressure and residual velocity, making the differentiated drainage measures for high and low permeability areas not strong enough in pertinence, and unable to dynamically adjust the drainage parameters according to the rainfall duration and risk changes, affecting the timeliness and effectiveness of the control measures. SUMMARY

[0005] The main purpose of the present application is to provide a slope stability analysis and dynamic feedback method based on heavy rainfall conditions, which accurately identifies the sliding risk area and dynamically adjusts the drainage optimization scheme by constructing a three-dimensional model of heterogeneous slope, coupling the dynamic changes of seepage and stress field, and monitoring the residual velocity of potential sliding surface, to realize the accurate analysis and effective dynamic feedback regulation of slope stability under heavy rainfall conditions.

[0006] One main aspect of the present application is to provide a slope stability analysis and dynamic feedback method based on heavy rainfall conditions, comprising the following steps executed by a computer system:

[0007] The terrain data, the geological radar scanning result and the meteorological rainfall parameter are integrated in a computer system to construct a heterogeneous slope model, the unit is divided and the lithology zoning parameter is determined; the infiltration line moving direction is deduced, the infiltration line maximum range is determined, and the heterogeneous slope longitudinal section thermal map of different rainfall duration is generated;

[0008] A two-way coupling model of unsaturated-saturated seepage field and stress field is established, the infiltration line moving and the plastic strain zone expansion are tracked, and the evolution of the safety factor with rainfall duration is calculated;

[0009] When the safety factor reaches a set threshold, the potential sliding surface displacement increment is monitored and the residual velocity is calculated, a residual velocity series changing with rainfall duration under the same safety factor is formed, and is marked on the longitudinal section thermal map;

[0010] Based on the infiltration line position, the pore water pressure distribution and the safety factor, the residual velocity series is combined to identify the sliding risk area, an optimized drainage scheme is designed and the parameters are dynamically adjusted.

[0011] As a further preferred scheme, in the foregoing method, the terrain data is collected by a drone at a set resolution; the geological radar scanning result at least includes three-dimensional fracture distribution data; the meteorological rainfall parameter at least includes rainfall intensity and duration; the lithology zoning parameter at least includes saturated permeability coefficient, saturated water content θ s and residual water content θ r .

[0012] As a further preferred scheme, in the foregoing method, before the deducing the infiltration line moving direction, it further includes marking the fracture position, occurrence and weak interlayer coordinates in the heterogeneous slope model, determining the potential sliding surface length and sliding direction; embedding the initial position of the infiltration line and the initial groundwater level line, and setting a safety factor threshold.

[0013] As a further preferred scheme, in the foregoing method, the two-way coupling model of unsaturated-saturated seepage field and stress field is established by using a finite element-discrete element hybrid algorithm, and the initial groundwater level line and the maximum range of the infiltration line moving are used to define the boundary of the saturated area, wherein the real-time position of the infiltration line represents the dynamic boundary of the saturated area.

[0014] As a further preferred scheme, in the foregoing method, the calculation of the evolution of the safety factor with rainfall duration includes: discretizing the rainfall duration according to a time step Δt=0.1h, and iteratively solving the seepage field and the stress field;

[0015] The soil strength parameters are corrected based on the volume water content θ:

[0016] c′=c0·(1-aθ)

[0017]

[0018] wherein a and b are intensity attenuation coefficients, determined by experiment;

[0019] The finite element strength reduction method is used to calculate the critical reduction coefficient as a safety factor.

[0020] As a further preferred scheme, in the foregoing method, the calculation and marking of the residual velocity include:

[0021] The displacement increment Δd is acquired in real time by a monitoring device arranged at the potential sliding surface, and the residual velocity

[0022] The v r values corresponding to different rainfall durations under the same safety factor are formed into a sequence, and are superimposed and marked at the corresponding positions of the longitudinal profile thermal map;

[0023] The monitoring is continued until the plastic strain zone extends to more than 80% of the length of the potential sliding surface.

[0024] As a further preferred scheme, in the foregoing method, the design drainage optimization scheme includes: for the high-permeability zone, the drainage hole spacing is increased and a filter layer is added; and for the weak interlayer low-permeability zone, a vacuum negative pressure drainage device is used.

[0025] The dynamic adjustment parameters include adjustment of hole coordinates, hole diameters and pumping rates, and the pumping rate is dynamically adjusted according to the residual velocity sequence.

[0026] As a further preferred scheme, in the foregoing method, the establishment of the unsaturated-saturated seepage field and stress field two-way coupling model further includes: a modified Van Genuchten model is used to describe the nonlinear relationship between matric suction and water content, and the unsaturated-saturated seepage field and stress field two-way coupling model is expressed according to the following formula:

[0027]

[0028] wherein θ is the volume water content, θ r is the residual water content, and θ s is the saturated water content, ψ is the matric suction, α, n and m are fitting parameters, obtained through indoor soil water characteristic curve tests, and are assigned according to lithology zoning, wherein α is inversely proportional to the air entry value of the soil body, reflecting the critical suction when the soil body starts to drain, and is a pressure reciprocal, n describes the curvature of the soil water characteristic curve, reflecting the uniformity of the pore size distribution, and is dimensionless, m is a parameter derived from n, controlling the flatness of the residual section of the curve, and is dimensionless, and m = 1-1 / n.

[0029] Another main aspect of the present application is to provide a slope stability analysis system, comprising:

[0030] The data integration module is used to process the terrain data of a set resolution collected by UAVs, the results of three-dimensional geological radar scanning, and meteorological and rainfall parameters, and to construct a three-dimensional model of a heterogeneous slope using GIS software.

[0031] The model processing module is used to divide the model into finite element units, perform lithological partitioning, and determine the saturated permeability coefficient, saturated water content, residual water content, fracture location, distribution of weak interlayers, potential sliding surface parameters, initial location of the phreatic line, and initial groundwater level.

[0032] The heat map generation module is used to extrapolate the movement of the wetting line and generate longitudinal profile heat maps;

[0033] The coupled model module uses a hybrid finite element-discrete element algorithm to establish a two-way coupled model of the unsaturated-saturated seepage field and stress field, so as to track the wetting line and plastic strain zone in real time and calculate the evolution of the safety factor.

[0034] The dynamic feedback module receives displacement increment data from the displacement monitoring device to calculate the residual velocity when the safety factor reaches the threshold, forms a series of data and marks it on the heat map.

[0035] The optimization module is used to identify areas of high pore water pressure and sliding risk areas, design drainage optimization schemes, and dynamically adjust drainage parameters.

[0036] Another key aspect of the present invention is to provide a computer program product comprising a computer-readable storage medium having stored thereon computer program instructions that, when executed by a processor, implement one or a combination of the steps of the aforementioned method:

[0037] The computer program instructions include at least:

[0038] Code used to integrate terrain data, 3D ground-penetrating radar scan results and meteorological and precipitation parameters to construct a 3D model of a heterogeneous slope;

[0039] Code used to divide finite element units, lithological zones, and determine saturated permeability coefficient, saturated water content, and residual water content;

[0040] Codes for marking fissures, weak interlayers, potential sliding surfaces, embedded seepage lines, and groundwater levels; codes for simulating seepage line movement and generating heat maps;

[0041] Code used to establish a two-way coupled model of unsaturated-saturated seepage field and stress field and calculate the evolution of safety factor;

[0042] Code used to collect displacement increments, calculate residual velocities, and label them when the safety factor reaches a threshold;

[0043] Code used to identify high pore water pressure zones and risk areas, and to design drainage optimization schemes.

[0044] Compared with existing technologies, this invention effectively improves the basic accuracy of slope stability analysis by constructing a three-dimensional model of a heterogeneous slope. The model integrates UAV topographic data, three-dimensional ground-penetrating radar results, and meteorological parameters, accurately marking heterogeneous features such as fissures and weak interlayers, dividing lithological zones and assigning key hydrological parameters. This overcomes the deviation between the traditional homogeneous assumption and actual geological conditions, providing a realistic geometric and parametric basis for subsequent seepage field and stress field analysis.

[0045] The two-way coupled model of unsaturated-saturated seepage field and stress field established in this invention realizes dynamic time-varying analysis of slope stability. By tracking the movement of the seepage line and the expansion of the plastic strain zone, and combining the strength reduction method to correct the strength parameters of the soil and rock mass in real time, the safety factor under different rainfall durations is accurately calculated. This overcomes the problem that traditional methods do not adequately consider the seepage-stress coupling and strength attenuation law, making the evolution of the safety factor more consistent with the actual stability changes under rainfall conditions.

[0046] This invention enhances the accurate identification of sliding risks by monitoring residual velocity and annotating with thermal maps. When the safety factor reaches a threshold, the potential sliding surface displacement increment is collected in real time and the residual velocity series is calculated. Combined with a thermal map, the risk distribution is presented intuitively, solving the problem of insufficient integration of monitoring data and simulation results in traditional technologies. This provides a quantitative basis for the early identification of concentrated sliding risk areas.

[0047] The drainage optimization scheme of this invention achieves a balance between specificity and dynamism. Based on the analysis results of the wetting line, pore water pressure, and residual velocity, the drainage holes are densified and a reverse filter layer is installed in the high-permeability zone, while vacuum negative pressure drainage is adopted in the low-permeability zone. Furthermore, the parameters are dynamically adjusted according to the changes in residual velocity, overcoming the shortcomings of traditional drainage schemes that rely on experience and lack specificity, and significantly improving the effectiveness of slope drainage control under heavy rainfall conditions.

[0048] In summary, this invention comprehensively improves the accuracy, dynamic response capability, and prevention and control effectiveness of slope stability analysis under heavy rainfall conditions through the synergy of model construction, coupled analysis, risk monitoring, and drainage regulation. It provides systematic technical support for slope engineering safety and reduces the risk of rainfall-induced landslide disasters. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, obtaining other drawings based on these drawings without creative effort still falls within the scope of the present invention.

[0050] Figure 1 This is an execution flowchart of an embodiment of the present invention;

[0051] Figure 2 This is an original topographic map of a slope according to an embodiment of the present invention;

[0052] Figure 3 This is a thermal diagram of a longitudinal profile of a slope according to an embodiment of the present invention. Detailed Implementation

[0053] The preferred embodiments of the present invention will be described in detail below to provide a clearer understanding of the purpose, features, and advantages of the invention. It should be understood that the following embodiments are not intended to limit the scope of the invention, but are merely illustrative of the essential spirit of the technical solution of the invention.

[0054] In the following description, certain specific details are set forth for the purpose of illustrating various disclosed embodiments in order to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the art will recognize that embodiments may be practiced without one or more of these specific details. In other instances, well-known techniques associated with the invention may not have been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0055] Throughout this specification, references to "an embodiment" or "an embodiment" indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Therefore, the appearance of "in an embodiment" or "an embodiment" in various places throughout the specification does not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic may be combined in any manner in one or more embodiments.

[0056] like Figure 1 As shown, in one possible embodiment, a slope stability analysis and dynamic feedback method based on heavy rainfall conditions includes the following steps performed by a computer system:

[0057] S110 integrates topographic data, ground-penetrating radar scan results, and meteorological and rainfall parameters in the computer system to construct a heterogeneous slope model, divides the slope into units and determines lithological zoning parameters; it also infers the direction of the phreatic line movement, determines the maximum range of the phreatic line, and generates longitudinal profile heat maps of heterogeneous slopes with different rainfall durations.

[0058] S120, establish a two-way coupled model of unsaturated-saturated seepage field and stress field, track the movement of the wetting line and the expansion of the plastic strain zone, and calculate the evolution of the safety factor with rainfall duration;

[0059] S130, when the safety factor reaches the set threshold, monitor the potential sliding surface displacement increment and calculate the residual velocity to form a residual velocity series that varies with rainfall duration under the same safety factor, and mark it on the longitudinal profile heat map;

[0060] S140, based on the location of the wetting line, the pore water pressure distribution and the safety factor, combined with the residual velocity sequence, the sliding risk zone is identified, a drainage optimization scheme is designed and the parameters are dynamically adjusted.

[0061] Specifically, when integrating terrain and other data in the computer system in S110, the computer system integrates terrain data from the UAV under a set resolution, 3D ground-penetrating radar scan results, and meteorological and rainfall parameters. Based on the terrain data, 3D ground-penetrating radar scan results, and meteorological and rainfall parameters, an original slope topographic map is drawn (e.g., Figure 2 (as shown), and then a three-dimensional model of the heterogeneous slope is constructed using GIS software.

[0062] In one feasible implementation, the heterogeneous slope three-dimensional model is divided into finite element units and lithological zones. Based on geological exploration experiments or regional hydrogeological experience databases, the saturated permeability coefficient, saturated water content, and residual water content of each lithological zone are determined.

[0063] Furthermore, the locations, attitudes, and coordinates of weak interlayers constructed by three-dimensional ground-penetrating radar scanning are labeled to determine the length and direction of the potential sliding surface. At the same time, geometric parameters, including the initial location of the seepage line and the initial groundwater level, are embedded into the three-dimensional model of the heterogeneous slope, and a safety factor threshold is set.

[0064] In a feasible implementation, in S110, it is also necessary to deduce the direction of the phreatic line migration of the three-dimensional model of the heterogeneous slope under different rainfall durations, determine the maximum range of phreatic line migration, and measure the saturated permeability coefficient; generate thermal maps of the longitudinal profile of the heterogeneous slope under different rainfall durations to intuitively determine the impact of rainfall on the longitudinal profile of the slope.

[0065] In a feasible implementation, step S120 employs a finite element-discrete element hybrid algorithm to establish a two-way coupled model of the unsaturated-saturated seepage field and stress field, track the wetting line migration path and the expansion of the plastic strain zone in real time, and calculate the evolution of the safety factor with rainfall duration. The specific steps are as follows:

[0066] The saturated zone boundary is determined based on the initial groundwater level and the maximum displacement of the phreatic line marked in S1. (The initial groundwater level serves as the initial reference for the saturated zone boundary, the real-time position of the phreatic line represents the dynamic state of the saturated zone boundary, and the maximum displacement of the phreatic line defines the extreme position that the saturated zone boundary can reach. When the phreatic line rises, the saturated zone boundary expands towards the upper part of the soil; when the phreatic line falls, the saturated zone boundary contracts towards the initial groundwater level. The maximum displacement reflects the upper and lower limits of the saturated zone boundary's change.)

[0067] A hybrid finite element-discrete element algorithm is adopted, and a modified Van Genuchten model is used to describe the nonlinear relationship between matrix suction and water content. The following bidirectional coupled model of unsaturated-saturated seepage field and stress field is established:

[0068]

[0069] Where θ is the volumetric water content, θ r θ represents the residual moisture content. s ψ represents saturated water content, α represents matrix suction, and α, n, and m are fitting parameters obtained through indoor soil-water characteristic curve tests and assigned values ​​according to lithological zones. Among them, α is inversely proportional to the air inlet value of the soil and reflects the critical suction when the soil begins to drain, with the unit being the reciprocal of pressure. n describes the curvature of the soil-water characteristic curve, reflecting the uniformity of pore size distribution, and is dimensionless. m is a parameter derived from n, controlling the smoothness of the residual segment of the curve, and is dimensionless (m = 1 - 1 / n).

[0070] Using the boundary of the saturated zone (ψ>0 above the initial groundwater level and ψ=0 below it) as the starting point for calculating the seepage field, the matrix suction ψ=0 and the water content θ=θ s The volumetric water content θ of the finite element units in the three-dimensional model of the heterogeneous slope is calculated sequentially, and the unsaturated permeability coefficient K(θ) is calculated using the Mualem formula:

[0071]

[0072] Among them, K s The saturated permeability coefficient;

[0073] Solve by simultaneously solving the Richards equation and the elastoplastic control equation;

[0074]

[0075] Where θ is the volumetric water content, t is the rainfall duration, K(θ) is the unsaturated permeability coefficient, h is the water head, and Q is the source-sink term; the boundary conditions are: the top surface of the slope is the rainfall infiltration boundary (source-sink term = Q), and the bottom surface is the constant water head boundary (h = the initial groundwater level determined in S1).

[0076] In addition, in the above formula, The gradient operator (Nabla operator) is a vector differential operator. In the formula for calculating the seepage field, The gradient represents the water head h, describing the rate and direction of change of the water head in space; while This indicates divergence operations, used to calculate the flux source strength of a vector field, such as... This represents the relationship between the unsaturated permeability coefficient K(θ) and the hydraulic head gradient. The divergence of the vector field formed by the product of is used to describe the spatial variation characteristics of water flux during seepage.

[0077] The rainfall duration is discretized by time step (e.g., Δt = 0.1h), and the distribution of θ and water head h is solved iteratively to track the path of the infiltration line and the expansion of the plastic strain zone in real time.

[0078] In a feasible implementation, step S120 further employs the finite element strength reduction method to calculate the evolution of the safety factor over rainfall duration. The specific steps are as follows:

[0079] Within the framework of the finite element strength reduction method, the actual water content state of each element of the soil and rock mass is first determined based on the calculation results of the seepage field at the current time step, namely the volumetric water content and the distribution of water head h.

[0080] Based on moisture content and soil strength parameters such as cohesion c and internal friction angle The correspondence between the original strength parameters c0 and c0 of each element. After correction, the effective strength parameter c′ at the current moisture content is obtained.

[0081] c′=c0·(1-aθ)

[0082]

[0083] Where a and b are intensity attenuation coefficients, which are determined through experiments;

[0084] Subsequently, a strength reduction factor F is introduced to reduce the corrected strength parameters to c′ / F and And substitute it into the stress field equilibrium equation of the finite element model: In the formula, σ is the stress tensor and f is the self-weight. The reduced stress, strain and displacement distribution are obtained by iterative solution.

[0085] Determine whether the slope has reached the limit equilibrium state under the current reduction factor. If signs such as displacement divergence, stress non-convergence, or plastic zone penetration appear during the finite element calculation, the slope is considered to have failed, and the corresponding reduction factor is the safety factor. If the calculation converges, it means that the slope is still in a stable state, and the reduction factor F needs to be increased. Repeat the above reduction-solution process until the calculation fails to converge.

[0086] This process determines the critical reduction factor, or safety factor, for a slope from stability to instability through a stepwise approximation method. The specific method is described below, but this algorithm is based on existing technology:

[0087] (1) Substituting the reduced cohesion c / F and the internal friction angle φ′=arctan(tanφ / F) into the Mohr-Coulomb yield criterion, the corrected yield function is: (σ1 and σ3 are the maximum and minimum principal stresses);

[0088] (2) Using the principle of virtual work, the equilibrium equation is solved Transform into weak form ∫ Ω δε T σdΩ=∫ Ω δu T fdΩ+∫ Γ δu T tdΓ(δu is the virtual displacement, For the sake of adapting to change ( (representing the symmetric gradient), f is the volume force or self-weight, t is the surface force, Ω is the solution domain, and Γ is the load boundary.

[0089] (3) Using the shape function u(x)=∑N i u i Discrete model, strain is expressed as ε = Bu e (B is the strain matrix, u) e (This refers to the displacement of the element nodes);

[0090] (4) Total strain ε = ε in the elastic-plastic stage e +ε p (ε e ,ε p For elastic and plastic strains, the stress is determined by the elastic-plastic tangent stiffness matrix D. ep Decision (σ=D) e (ε-ε p ), D e (This is the elastic stiffness matrix);

[0091] (5) Assemble the tangent stiffness matrix K ep =∫ Ω B T D ep BdΩ is solved iteratively using the Newton-Raphson method. (R(u i )=F-∫ Ω B T σ i dΩ represents the unbalanced force, update the displacement u. i+1 =u i +Δu i The process is iterated until convergence or displacement divergence occurs, and finally the slope safety factor is determined by the critical reduction factor F.

[0092] Finally, in the two-way coupled model, the seepage field within each time step dynamically evolves with the increase of rainfall duration, such as the rise of the phreatic line and the distribution of pore water pressure, which in turn leads to the continuous adjustment of the soil and rock water content and strength parameters over time. Therefore, the above-mentioned cyclic process of seepage field update - strength parameter correction - strength reduction - stress field solution - stability judgment needs to be repeated within each time step to finally obtain the dynamic evolution results of the slope safety factor under different rainfall durations.

[0093] This process achieves time-varying analysis of slope stability under rainfall conditions by coupling the interaction between the seepage field and the stress field, ensuring that the safety factor calculation can reflect the dynamic influence of actual hydrogeological conditions.

[0094] In one feasible implementation, in step S130, when the safety factor calculated in the previous step reaches the previously set safety factor threshold in the system, the displacement monitoring equipment deployed on the slope collects the displacement increments corresponding to different rainfall durations in real time in the potential sliding surface area. The computer system calculates the residual velocity using the following formula, forming a residual velocity series that varies with rainfall duration under the same safety factor, until the plastic strain zone expands to above the set range of the potential sliding surface length:

[0095]

[0096] Among them, v r The residual velocity is Δd, the displacement increment of the sliding surface is obtained through monitoring equipment, and Δt is the corresponding time interval.

[0097] The safety factor and residual velocity series are marked on the longitudinal profile heat map of the homogeneous slope obtained in the previous steps, such as... Figure 3 As shown.

[0098] In one feasible implementation, step S140, based on the location of the seepage line, the distribution of pore water pressure, and the safety factor output in the previous steps, and combined with the residual velocity series marked on the longitudinal profile heat map of the heterogeneous slope, identifies the high pore water pressure zone at the leading edge of the seepage line and the area of ​​concentrated sliding risk where the residual velocity is greater than the set value, and designs a targeted drainage optimization scheme. For example, some feasible implementations include: increasing the spacing of drainage holes and adding a reverse filter layer in high seepage zones, and using a vacuum negative pressure drainage device in low seepage zones such as weak interlayers to improve drainage efficiency.

[0099] Furthermore, in some feasible implementations, drainage parameters are dynamically adjusted based on the residual velocity sequence to form a real-time control strategy that includes orifice coordinates, orifice diameter, and pumping rate.

[0100] This invention provides a slope stability analysis and dynamic feedback system based on heavy rainfall conditions, comprising:

[0101] The data integration module is used to process the terrain data of a set resolution collected by UAVs, the results of three-dimensional geological radar scanning, and meteorological and rainfall parameters, and to construct a three-dimensional model of a heterogeneous slope using GIS software.

[0102] The model processing module is used to divide the model into finite element units, perform lithological partitioning, and determine the saturated permeability coefficient, saturated water content, residual water content, fracture location, distribution of weak interlayers, potential sliding surface parameters, initial location of the phreatic line, and initial groundwater level.

[0103] The heat map generation module is used to extrapolate the movement of the wetting line and generate longitudinal profile heat maps;

[0104] The coupled model module uses a hybrid finite element-discrete element algorithm to establish a two-way coupled model of the unsaturated-saturated seepage field and stress field, so as to track the wetting line and plastic strain zone in real time and calculate the evolution of the safety factor.

[0105] The dynamic feedback module receives displacement increment data from the displacement monitoring device to calculate the residual velocity when the safety factor reaches the threshold, forms a series of data and marks it on the heat map.

[0106] The optimization module is used to identify high pore water pressure zones and sliding risk areas, design drainage optimization schemes, and dynamically adjust parameters.

[0107] The foregoing has shown and described the basic principles and main features of the present invention, as well as its advantages. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A slope stability analysis and dynamic feedback method based on heavy rainfall conditions, characterized in that, This includes the following steps performed by the computer system: Integrate topographic data, ground-penetrating radar scan results, and meteorological and rainfall parameters into a computer system to construct a heterogeneous slope model, divide it into units, and determine lithological zoning parameters; deduce the direction of phreatic line movement, determine the maximum range of the phreatic line, and generate longitudinal profile heat maps of heterogeneous slopes with different rainfall durations. A two-way coupled model of unsaturated-saturated seepage field and stress field was established to track the movement of the wetting line and the expansion of the plastic strain zone, and to calculate the evolution of the safety factor with rainfall duration. When the safety factor reaches a set threshold, the potential sliding surface displacement increment is monitored and the residual velocity is calculated to form a residual velocity series that varies with rainfall duration under the same safety factor, and is marked on the longitudinal profile heat map. Based on the location of the wetting line, the pore water pressure distribution, and the safety factor, the sliding risk zone is identified by combining the residual velocity sequence, and a drainage optimization scheme is designed and the parameters are dynamically adjusted.

2. The slope stability analysis and dynamic feedback method based on heavy rainfall conditions according to claim 1, characterized in that, The terrain data was collected by a drone at a set resolution; the ground-penetrating radar scan results included at least three-dimensional fracture distribution data; the meteorological and precipitation parameters included at least rainfall intensity and duration; the lithological zoning parameters included at least saturated permeability coefficient and saturated water content θ. s and residual moisture content θ r .

3. The slope stability analysis and dynamic feedback method based on heavy rainfall conditions according to claim 1, characterized in that, Before deriving the direction of the phreatic line movement, the model also includes marking the location, attitude, and coordinates of weak interlayers in the heterogeneous slope model to determine the length and direction of the potential sliding surface; embedding the initial location of the phreatic line and the initial groundwater level line; and setting a safety factor threshold.

4. The slope stability analysis and dynamic feedback method based on heavy rainfall conditions according to any one of claims 1-3, characterized in that, The establishment of the bidirectional coupling model of unsaturated-saturated seepage field and stress field adopts a finite element-discrete element hybrid algorithm. The boundary of the saturated zone is defined by the maximum range of the initial groundwater level and the phreatic line, where the real-time position of the phreatic line represents the dynamic boundary of the saturated zone.

5. The slope stability analysis and dynamic feedback method based on heavy rainfall conditions according to any one of claims 1-3, characterized in that, The calculation of the safety factor as a function of rainfall duration includes: discretizing the rainfall duration at a time step of Δt = 0.1h and iteratively solving the seepage field and stress field; Correction of soil and rock strength parameters based on volumetric water content θ: c′=c0·(1-aθ) Where a and b are intensity attenuation coefficients, which are determined through experiments; The critical reduction factor is calculated using the finite element strength reduction method and used as the safety factor.

6. The slope stability analysis and dynamic feedback method based on heavy rainfall conditions according to any one of claims 1-3, characterized in that, The calculation and labeling of the residual velocity includes: The displacement increment Δd is collected in real time by monitoring equipment arranged on the potential sliding surface, and the residual velocity... v corresponding to different rainfall durations under the same safety factor r The values ​​form a series and are superimposed and labeled at the corresponding positions on the longitudinal profile heat map; Continue monitoring until the plastic strain zone extends to more than 80% of the potential sliding surface length.

7. The slope stability analysis and dynamic feedback method based on heavy rainfall conditions according to any one of claims 1-3, characterized in that, The drainage optimization design scheme includes increasing the spacing of drainage holes and adding a reverse filter layer in high-permeability zones; and using a vacuum negative pressure drainage device in low-permeability zones of weak interlayers. The dynamic adjustment parameters include adjusting the orifice coordinates, orifice diameter, and pumping rate, and the pumping rate is dynamically adjusted according to the residual velocity series.

8. The slope stability analysis and dynamic feedback method based on heavy rainfall conditions according to claim 4, characterized in that, The establishment of the bidirectional coupling model between the unsaturated and saturated seepage fields and the stress field further includes: describing the nonlinear relationship between matrix suction and water content using a modified Van Genuchten model, and expressing the bidirectional coupling model between the unsaturated and saturated seepage fields and the stress field according to the following formula: Where θ is the volumetric water content, θ r For residual moisture content, θ s ψ represents the saturated water content, α represents the matrix suction, and α, n, and m are fitting parameters obtained through indoor soil-water characteristic curve tests. They are assigned values ​​according to lithological zones. α is inversely proportional to the air intake value of the soil and reflects the critical suction when the soil begins to drain. The unit is the reciprocal of pressure. n describes the curvature of the soil-water characteristic curve, reflecting the uniformity of pore size distribution. It is dimensionless. m is a parameter derived from n, controlling the smoothness of the residual segment of the curve. It is dimensionless, and m = 1 - 1 / n.

9. A slope stability analysis and dynamic feedback system based on heavy rainfall conditions, characterized in that, include: The data integration module is used to process the terrain data of a set resolution collected by UAVs, the results of three-dimensional geological radar scanning, and meteorological and rainfall parameters, and to construct a three-dimensional model of a heterogeneous slope using GIS software. The model processing module is used to divide the model into finite element units, perform lithological partitioning, and determine the saturated permeability coefficient, saturated water content, residual water content, fracture location, distribution of weak interlayers, potential sliding surface parameters, initial location of the phreatic line, and initial groundwater level. The heat map generation module is used to extrapolate the movement of the wetting line and generate longitudinal profile heat maps; The coupled model module uses a hybrid finite element-discrete element algorithm to establish a two-way coupled model of the unsaturated-saturated seepage field and stress field, so as to track the wetting line and plastic strain zone in real time and calculate the evolution of the safety factor. The dynamic feedback module receives displacement increment data from the displacement monitoring device to calculate the residual velocity when the safety factor reaches the threshold, forms a series of data and marks it on the heat map. The optimization module is used to identify high pore water pressure zones and sliding risk areas, design drainage optimization schemes, and dynamically adjust parameters.

10. A computer program product comprising a computer-readable storage medium having computer program instructions stored thereon, characterized in that, The computer program instructions, when executed by a processor, implement the method of any one of claims 1-8.

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