A slope instability evaluation method based on deformation monitoring data

Abstract

The application discloses a kind of based on deformation monitoring data's slope instability evaluation method, it is related to slope engineering monitoring data analysis field, method is: obtaining the related data such as topography, stratum, foundation monitoring point in the range around slope;According to the distribution of deformation foundation monitoring point and deformation fitting potential sliding surface;Establish three-dimensional finite element model of slope, and determine the cohesion and internal friction angle of potential sliding surface by inversion;The inversion cohesion and internal friction angle of sliding surface are calculated by strength reduction method, and the safety factor of slope is determined;According to the horizontal displacement direction of foundation monitoring point and potential unstable slope body, the sliding direction of slope is determined;Finally, the slope, potential unstable slope body and its sliding direction are displayed through visual platform, and the volume of potential unstable slope body and the safety factor of slope are displayed by text.The application determines the three-dimensional sliding surface of slope by surface fitting, and then calculates the safety factor of slope by parameter inversion and strength reduction method, realizes the early warning description of slope instability form including instability volume, direction and other characteristics.

Description

Technical Field

[0001] This invention relates to the field of engineering monitoring technology, and in particular to a method for assessing slope instability based on deformation monitoring data. Background Technology

[0002] Slope engineering monitoring technologies are complex, and deformation is the most direct indicator of slope instability. Existing slope deformation monitoring methods mainly fall into two categories: ground deformation monitoring and hollow-foundation deformation monitoring. Ground deformation monitoring primarily uses deformation sensors installed on or inside the slope surface to capture slope deformation; hollow-foundation deformation monitoring mainly uses drones or satellites equipped with radar to periodically scan the slope to capture slope deformation. Ground deformation monitoring is characterized by point-like, high-frequency activity; hollow-foundation deformation monitoring is characterized by area-like, low-frequency activity.

[0003] Foundation deformation monitoring should be characterized by high frequency and timeliness. Therefore, foundation deformation monitoring is often the primary method in slope monitoring. In analyzing foundation deformation monitoring data, technicians typically use threshold-based early warning systems, such as the slope monitoring early warning method disclosed in Chinese invention patent CN117195610A. This method determines the stability early warning value for any monitoring point on the slope to be monitored using multiple slope surfaces. If the stability early warning value is greater than or equal to a preset threshold, an early warning is issued for the monitoring point. However, this early warning method can only simply reflect the stability state of the slope and cannot reflect the volume or direction of potential slope instability and slippage. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention provides a slope instability assessment method based on deformation monitoring data. The method assesses the potential instability morphology of the slope by fitting a three-dimensional slip surface, and determines the magnitude of the slope instability probability by inversion and strength reduction.

[0005] To achieve the above objectives, the present invention adopts the following technical solution, including:

[0006] A slope instability assessment method based on deformation monitoring data includes the following steps:

[0007] Step 1: Obtain topographic data, stratigraphic data, spatial coordinates of foundation monitoring points, deformation monitoring data of foundation monitoring points, and physical parameters of rock / soil in the surrounding area of ​​the slope;

[0008] The foundation monitoring points include slope monitoring points and in-slope monitoring points; the foundation monitoring points are distributed in multiple monitoring sections; the monitoring sections are parallel to the slope orientation, and each monitoring section contains both slope monitoring points and in-slope monitoring points;

[0009] The deformation monitoring data specifically includes: the monitored horizontal displacement vector and the monitored vertical displacement vector of the slope monitoring point; the monitored horizontal displacement vector of the monitoring point inside the slope; the deformation monitoring data of the monitoring point inside the slope is obtained by an inclinometer, which is installed in the inclinometer hole, and at least one inclinometer is installed in the same inclinometer hole;

[0010] The physical parameters of the rock / soil include unit weight, elastic modulus, Poisson's ratio, cohesion, and internal friction angle;

[0011] Step 2: Obtain the spatial coordinates and deformation monitoring data of foundation monitoring points that exhibit deformation within the same time period. These foundation monitoring points are referred to as deformed foundation monitoring points, which can be further subdivided into deformed slope monitoring points and deformed slope intra-point monitoring points. Then, fit the potential sliding surface based on the distribution of deformed foundation monitoring points and the cumulative deformation.

[0012] Step 3: Establish a three-dimensional finite element model of the slope, and determine the inversion cohesion and inversion internal friction angle of the potential sliding surface through inversion.

[0013] Step 4: Use the strength reduction method to reduce the inverted cohesion and inverted internal friction angle of the potential sliding surface to determine the safety factor of the slope;

[0014] Step 5: Determine the slope sliding direction based on the horizontal displacement direction of the foundation monitoring points and the potential unstable slope body;

[0015] Step 6: Display the slope, potentially unstable slope body and its sliding direction through a visualization platform, and show the volume of the potentially unstable slope body and the safety factor of the slope.

[0016] Preferably, in step 2, the fitting of the potential sliding surface based on the distribution of deformation foundation monitoring points and cumulative deformation is as follows:

[0017] Step 2.1: Obtain all monitoring sections of the foundation with deformation monitoring points, which are called deformation monitoring sections;

[0018] Step 2.2: Obtain all foundation monitoring points within the deformation monitoring section, and determine multiple constraint line segments based on the deformation foundation monitoring points and the remaining foundation monitoring points;

[0019] Step 2.3: Fit an ellipsoid that minimizes the objective function in space as a potential sliding surface;

[0020] The objective function is equal to the sum of the constraint penalty function and the horizontal settlement ratio function.

[0021] Preferably, in step 2.2, the multiple constraint segments are specifically defined as follows: within the same monitoring section, a constraint segment is formed by taking the monitoring point of the deformed slope with the highest elevation as the endpoint and finding the nearest non-deformed slope monitoring point in the opposite direction of the slope orientation as the other endpoint, which is called the upper constraint segment; within the same monitoring section, a constraint segment is formed by taking the monitoring point of the deformed slope with the lowest elevation as the endpoint and finding the nearest non-deformed slope monitoring point in the direction of the slope orientation as the other endpoint, which is called the lower constraint segment; within the same inclinometer hole of the same monitoring section, a constraint segment is formed by connecting the monitoring point in the deformed slope with the nearest monitoring point in the non-deformed slope, which is called the inner constraint segment.

[0022] In step 2.3, the constraint penalty function is equal to the sum of the squares of the lengths of the intersecting segments of all the extended constraint line segments multiplied by the coefficient α;

[0023] The length of the extended intersection segment of the constraint line segment is specifically defined as follows: if the constraint line segment intersects with the ellipsoid, the length of the extended intersection segment of the constraint line segment is zero; if the constraint line segment does not intersect with the ellipsoid, the length of the extended intersection segment of the constraint line segment is determined by judgment extension.

[0024] The determination of the length of the intersection segment of the extended constraint line segment is as follows: Starting from the two endpoints of the constraint line segment, extend outwards to find the intersection point with the ellipsoid; determine a true intersection point according to the different constraint line segments; if a true intersection point exists, the distance between the true intersection point and the midpoint of the constraint line segment minus half the length of the constraint line segment, and then divided by one meter, is taken as the length of the intersection segment of the extended constraint line segment; wherein, if the constraint line segment is the upper constraint line segment, the intersection point with the largest elevation is taken as the true intersection point; otherwise, the intersection point with the smallest elevation is taken as the true intersection point; if no true intersection point exists, the length of the intersection segment of the extended constraint line segment is β.

[0025] Preferably, in step 2.3, the horizontal settlement ratio function is as follows:

[0026] Step 2.3.1: Obtain the horizontal displacement monitoring surface component and the vertical displacement vector of the monitoring point located inside the ellipsoidal deformation slope, and solve the ratio of the magnitude of the horizontal displacement monitoring surface component to the magnitude of the vertical displacement vector, denoted as the monitoring horizontal settlement ratio;

[0027] The horizontal displacement monitoring surface component refers to the component of the monitored horizontal displacement vector of the deformation slope monitoring point within the monitoring section.

[0028] Step 2.3.2: Solve for the similar ellipsoidal tangent vector of each deformation slope monitoring point located inside the ellipsoid within the monitoring section, and solve for the ratio of the horizontal component to the vertical component of the similar ellipsoidal tangent vector, denoted as the calculated horizontal settlement ratio;

[0029] The specific solution process for the tangent vector of the similar ellipsoid is as follows:

[0030] Step 2.3.2a: Construct a similar ellipsoid in space that is similar to the potential sliding surface. The similar ellipsoid must meet two requirements: the monitoring point of the deformed slope is located on the similar ellipsoid; the similar ellipsoid is obtained by keeping the ellipsoid center of the potential sliding surface unchanged and enlarging or reducing it by a certain proportion.

[0031] Step 2.3.2b: Find the intersection of the monitoring section and the similar ellipsoid to obtain a two-dimensional closed curve, and solve for a tangent vector of the deformed slope monitoring point in the two-dimensional closed curve as the similar ellipsoid tangent vector of the deformed slope monitoring point in the monitoring section; the horizontal component of the similar ellipsoid tangent vector is consistent with the slope orientation;

[0032] Step 2.3.3: Solve for the sum of squares of the differences between the monitored horizontal settlement ratio and the calculated horizontal settlement ratio at all deformation slope monitoring points, and use this as the horizontal settlement ratio function.

[0033] Preferably, in step 3, the inversion determines the inversion cohesion and inversion internal friction angle of the potential sliding surface, specifically as follows:

[0034] Step 3.1: Take the physical parameters of the potential sliding surface to be the same as those of the potential unstable slope, and achieve equilibrium under self-weight stress;

[0035] The potentially unstable slope body is the body obtained by cutting the slope with a potential sliding surface;

[0036] Step 3.2: Extract the calculated deformation of each foundation monitoring point from Step 3.1, and record it as the initial calculated deformation;

[0037] The initial calculated deformation data specifically includes: the initial calculated horizontal displacement vector and the initial calculated vertical displacement vector of the slope monitoring points; and the initial calculated horizontal displacement vector of the monitoring points within the slope.

[0038] Step 3.3: Obtain the cohesion c0 and internal friction angle ψ0 of the potential unstable slope; take positive integers m and n, and preset m-1 cohesion and n-1 internal friction angles according to (c0 / m, c0×2 / m, ..., c0×(m-1) / m) and (ψ0 / n, ψ0×2 / n, ..., ψ0×(n-1) / n) respectively, and combine the preset cohesion and internal friction angles to form (m-1)×(n-1) combinations of preset cohesion and internal friction angles;

[0039] Step 3.4: Replace the cohesion and internal friction angle of the potential sliding surface with different preset combinations of cohesion and internal friction angle in turn, and continue to calculate based on the results of Step 3.1. Extract the calculated deformation of each foundation monitoring point in the calculation results and record it as the sliding calculated deformation.

[0040] The specific data for sliding deformation calculation includes: the horizontal displacement vector and vertical displacement vector of the slope monitoring points; and the horizontal displacement vector of the monitoring points within the slope.

[0041] Step 3.5: Compare the differences between all the sliding calculated deformations and the initial calculated deformations with the deformation monitoring data of the foundation monitoring points, and select the set of preset cohesion and internal friction angles with the smallest deviation as the inversion cohesion and inversion internal friction angle of the potential sliding surface.

[0042] Preferably, in steps 3.2 and 3.4, the calculation of deformation of the foundation monitoring points specifically includes: calculating the horizontal displacement vector and calculating the vertical displacement vector of the slope monitoring points; and calculating the horizontal displacement vector of the monitoring points within the slope.

[0043] Preferably, in step 3.5, the minimum deviation refers to the minimum deviation function; the deviation function includes the slope monitoring point deviation function and the slope intra-monitoring point deviation function; the slope monitoring point deviation function is equal to the sum of the horizontal displacement vector deviations and vertical displacement vector deviations of all slope monitoring points; the slope intra-monitoring point deviation function is equal to the sum of the horizontal displacement vector deviations of all intra-slope monitoring points.

[0044] Let Xmon be the magnitude of the X component of the monitored horizontal displacement vector, Ymon be the magnitude of the monitored horizontal displacement vector, and Zmon be the magnitude of the monitored vertical displacement vector. Let Xcal1 be the initially calculated magnitude of the X component of the horizontal displacement vector, Ycal1 be the initially calculated magnitude of the Y component of the horizontal displacement vector, and Zcal1 be the initially calculated magnitude of the vertical displacement vector. Let Xcal2 be the magnitude of the slidingly calculated magnitude of the X component of the horizontal displacement vector, Ycal2 be the magnitude of the slidingly calculated magnitude of the horizontal displacement vector, and Zcal2 be the magnitude of the slidingly calculated vertical displacement vector. The sum of the deviations of the horizontal and vertical displacement vectors at the slope monitoring points is equal to (Xmon - (Xcal2 - Xcal1)). 2 +(Ymon-(Ycal2-Ycal1)) 2 +(Zmon-(Zcal2-Zcal1)) 2 The horizontal displacement vector deviation of the monitoring point within the slope is equal to (Xmon - (Xcal2 - Xcal1)). 2 +(Ymon-(Ycal2-Ycal1)) 2 .

[0045] Preferably, in step 5, the slope sliding direction is determined based on the horizontal displacement direction of the foundation monitoring points and the potentially unstable slope body, as follows:

[0046] Step 5.1: Use multiple sets of cutting surfaces with a spacing of 'a' in the X, Y, and Z directions to divide the potentially unstable slope body into multiple segments;

[0047] Step 5.2: Determine the direction of the horizontal displacement of each foundation monitoring point as the direction of the monitored horizontal displacement vector;

[0048] Step 5.3: Calculate the horizontal displacement direction of each segment. Specifically, based on the spatial location and horizontal movement direction of the foundation monitoring point, the horizontal displacement direction of each segment is determined by inverse distance interpolation.

[0049] The horizontal displacement direction of each segment is a vector with a magnitude of 1;

[0050] Step 5.4: Calculate the volume of all segments, multiply the volume of each segment by its horizontal displacement direction, and then sum all the vectors. The sum of these vectors is the horizontal sliding direction of the potentially unstable slope.

[0051] Preferably, in step 4, the strength reduction method is used to calculate the safety factor of the slope, specifically as follows:

[0052] The inversion cohesion and inversion internal friction angle of the potential sliding surface are continuously reduced until the finite element calculation results show that the slope is unstable. At this point, 1 is divided by the reduction factor to obtain the safety factor of the slope.

[0053] The present invention also provides a computer program product, including a computer program / instruction that, when executed by a processor, implements the above-described slope instability assessment method based on deformation monitoring data.

[0054] The advantages of this invention are:

[0055] (1) By fitting the sliding surface, the volume of the potentially unstable slope can be quantitatively calculated, thereby accurately assessing the hazards caused by slope instability.

[0056] (2) Inversion can more accurately calculate the physical parameters of the slope sliding surface, and then the safety factor can be calculated using the strength reduction method, which helps technicians to accurately understand the stability state of the slope. The safety factor represents the stability of the slope; the smaller the safety factor, the greater the possibility of instability.

[0057] (3) The sliding direction of the potentially unstable slope is calculated by spatial interpolation and vector summation, which is convenient for assessing the objects downstream of the slope that are at risk.

[0058] (4) This invention determines the three-dimensional slip surface of the slope by surface fitting, and then calculates the safety factor of the slope by parameter inversion and strength reduction method, thus realizing the early warning description of the slope instability mode including instability volume, direction and other characteristics. Attached Figure Description

[0059] Figure 1 This is a flowchart of the slope instability assessment method.

[0060] Figure 2 A top-down view of the slope monitoring points at the prefecture level is provided.

[0061] Figure 3 This is a layout diagram of the monitoring points for the slope foundation within the monitoring section.

[0062] Figure 4 A schematic diagram showing the segmentation of potentially unstable slopes within the monitoring section.

[0063] The attached figures are labeled as follows:

[0064] 1. Slope orientation; 2. Slope monitoring point; 3. Inclinometer; 4. Monitoring section; 5. Potential sliding surface; 6. Monitoring point within the slope; 7. Constraint line segment; 8. Similar ellipsoid; 9. Tangent vector of similar ellipsoid; 10. Segmentation volume. Detailed Implementation

[0065] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0066] Depend on Figures 1-4 As shown, a slope instability assessment method based on deformation monitoring data includes the following steps:

[0067] Step 1: Obtain topographic data, stratigraphic data, spatial coordinates of foundation monitoring points, deformation monitoring data of foundation monitoring points, and physical parameters of rock / soil in the surrounding area of ​​the slope.

[0068] The slope in question refers to a slope on which the potentially unstable slope body is a homogeneous rock / soil body; the homogeneous rock / soil body refers to the rock / soil body that is calculated using the same set of physical parameters.

[0069] The foundation monitoring points include slope monitoring points 2 and in-slope monitoring points 6; the foundation monitoring points are distributed in multiple monitoring sections 4; the monitoring sections 4 are parallel to the slope orientation 1, and each monitoring section 4 contains slope monitoring points 2 and in-slope monitoring points 6.

[0070] The deformation monitoring data are as follows: the deformation monitoring data of slope monitoring point 2 is acquired through a GNSS (Global Navigation Satellite System) receiver, including monitoring horizontal displacement vector and monitoring vertical displacement vector; the deformation monitoring data of monitoring point 6 inside the slope is acquired through an inclinometer 3, including monitoring horizontal displacement vector; the inclinometer 3 is installed in an inclinometer hole, and multiple inclinometers 3 are installed in the same inclinometer hole.

[0071] The physical parameters of the rock / soil include unit weight, elastic modulus, Poisson's ratio, cohesion, and internal friction angle.

[0072] Step 2: Obtain the spatial coordinates and deformation monitoring data of foundation monitoring points that are deformed in the same time period. The foundation monitoring points that are deformed are called deformed foundation monitoring points, which can be further subdivided into deformed slope monitoring points and deformed slope monitoring points. Based on the distribution of deformed foundation monitoring points and cumulative deformation, fit the potential sliding surface 5.

[0073] Step 2, which involves fitting the potential sliding surface 5 based on the distribution of deformation foundation monitoring points and cumulative deformation, is as follows:

[0074] Step 2.1: Obtain all monitoring sections 4 of the foundation with deformation monitoring points, which are called deformation monitoring sections.

[0075] Step 2.2: Obtain all foundation monitoring points within the deformation monitoring section, and determine multiple constraint line segments 7 based on the deformation foundation monitoring points and the remaining foundation monitoring points.

[0076] Step 2.2 describes determining multiple constraint segments 7 based on the deformed foundation monitoring points and other foundation monitoring points. Specifically, within the same monitoring section, a constraint segment 7 is formed by taking the deformed slope monitoring point with the highest elevation as the endpoint and finding the nearest non-deformed slope monitoring point in the opposite direction of the slope orientation as the other endpoint. This is called the upper constraint segment. Within the same monitoring section, a constraint segment 7 is formed by taking the deformed slope monitoring point with the lowest elevation as the endpoint and finding the nearest non-deformed slope monitoring point in the direction of the slope orientation as the other endpoint. This is called the lower constraint segment. Within the same inclinometer borehole 3 in the same monitoring section, a constraint segment 7 is formed by connecting the monitoring point within the deformed slope with the nearest non-deformed slope monitoring point. This is called the inner constraint segment.

[0077] Step 2.3: Fit an ellipsoid that minimizes the objective function in space as the potential sliding surface 5.

[0078] The objective function described in step 2.3 is equal to the sum of the constraint penalty function and the horizontal settlement ratio function.

[0079] The constraint penalty function is equal to the sum of the squares of the lengths of all extended intersection segments of the constraint line segment 7 multiplied by a coefficient α. Specifically, the length of the extended intersection segment of the constraint line segment is: if the constraint line segment 7 intersects with the ellipsoid, the length of the extended intersection segment of the constraint line segment is zero; if the constraint line segment 7 does not intersect with the ellipsoid, the length of the extended intersection segment of the constraint line segment is determined by a judgment extension.

[0080] The determination of the length of the intersection segment of the constraint line segment extension is as follows: taking the two endpoints of the constraint line segment 7 as the starting point, extend outward to find the intersection point with the ellipsoid; depending on the constraint line segment 7, determine a true intersection point; the distance between the true intersection point and the midpoint of the constraint line segment minus half the length of the constraint line segment, and then divided by one meter, is taken as the length of the intersection segment of the constraint line segment extension.

[0081] The determination of a true intersection point is as follows: if the constraint line segment 7 is the upper constraint line segment, then the intersection point with the largest elevation is taken as the true intersection point; otherwise, the intersection point with the smallest elevation is taken as the true intersection point.

[0082] Furthermore, the coefficient α is a real number greater than 0 that is manually set.

[0083] Furthermore, if the true intersection point does not exist, the length of the intersection segment of the constrained line segment extension is β; where β is a real number greater than 0.

[0084] The horizontal settlement ratio function is as follows:

[0085] Step 2.3.1: Obtain the horizontal displacement monitoring surface component and the vertical displacement vector of the monitoring point located inside the ellipsoidal deformation slope, and solve the ratio of the magnitude of the horizontal displacement monitoring surface component to the magnitude of the vertical displacement vector, denoted as the monitoring horizontal settlement ratio.

[0086] The horizontal displacement monitoring surface component refers to the component of the monitored horizontal displacement vector at the deformation slope monitoring point within the monitoring section.

[0087] Step 2.3.2: Solve for the similar ellipsoidal tangent vector 9 of each deformation slope monitoring point located inside the ellipsoid in the monitoring section 4, and solve for the ratio of the horizontal component to the vertical component of the similar ellipsoidal tangent vector 9, denoted as the calculated horizontal settlement ratio.

[0088] The specific solution process for the similar ellipsoidal tangent vector 9 of the deformation slope monitoring point within the monitoring section in step 2.3.2 is as follows:

[0089] Step 2.3.2a: Construct a similar ellipsoid 8 in space that is similar to the potential sliding surface 5. The similar ellipsoid satisfies two requirements: (1) The monitoring point of the deformed slope is located on the similar ellipsoid 8; (2) The similar ellipsoid 8 is obtained by keeping the ellipsoid center of the potential sliding surface 5 unchanged and enlarging or reducing it by a certain proportion.

[0090] Step 2.3.2b: Intersect the monitoring section 4 with the similar ellipsoid 8 to obtain a two-dimensional closed curve, and solve for a tangent vector of the deformed slope monitoring point in the two-dimensional closed curve as the similar ellipsoid tangent vector 9 of the deformed slope monitoring point in the monitoring section 4; the horizontal component of the similar ellipsoid tangent vector 9 is consistent with the slope orientation 1.

[0091] Step 2.3.3: Solve for the sum of squares of the differences between the monitored horizontal settlement ratio and the calculated horizontal settlement ratio at all deformation slope monitoring points, and use this as the horizontal settlement ratio function.

[0092] Step 3: Establish a three-dimensional finite element model of the slope, and determine the inversion cohesion and inversion internal friction angle of the potential sliding surface 5 through inversion.

[0093] The three-dimensional finite element model of the slope includes the rock / soil mass and the potential sliding surface 5 fitted in step 2.

[0094] The inversion determines the inversion cohesion and inversion internal friction angle of the potential sliding surface 5, as follows:

[0095] Step 3.1: Take the physical parameters of the potential sliding surface 5 to be the same as those of the potential unstable slope, and achieve equilibrium under self-weight stress.

[0096] The potentially unstable slope body is the body obtained by cutting the slope along the potential sliding surface 5.

[0097] Step 3.2: Extract the calculated deformation of each foundation monitoring point in Step 3.1 and record it as the initial calculated deformation.

[0098] The initial calculated deformation data are as follows: the initial calculated horizontal displacement vector and the initial calculated vertical displacement vector of monitoring point 2 on the slope; and the initial calculated horizontal displacement vector of monitoring point 6 within the slope.

[0099] Step 3.3: Obtain the cohesion c0 and internal friction angle ψ0 of the potential unstable slope; take positive integers m and n, and preset m-1 cohesion and n-1 internal friction angles according to (c0 / m, c0×2 / m, ..., c0×(m-1) / m) and (ψ0 / n, ψ0×2 / n, ..., ψ0×(n-1) / n) respectively, and combine the preset cohesion and internal friction angles to form (m-1)×(n-1) combinations of preset cohesion and internal friction angles.

[0100] Step 3.4: Replace the cohesion and internal friction angle of the potential sliding surface 5 with different preset cohesion and internal friction angle combinations in turn, and continue to calculate based on the results of step 3.1. Extract the calculated deformation of each foundation monitoring point in the calculation results and record it as the sliding calculated deformation.

[0101] The specific sliding deformation data are: the sliding calculation horizontal displacement vector and sliding calculation vertical displacement vector of monitoring point 2 on the slope; and the sliding calculation horizontal displacement vector of monitoring point 6 inside the slope.

[0102] Step 3.5: Compare the differences between all the sliding calculated deformations and the initial calculated deformations with the deformation monitoring data of the foundation monitoring points, and select the set of preset cohesion and internal friction angles with the smallest deviation as the inversion cohesion and inversion internal friction angle of the potential sliding surface 5.

[0103] The calculation deformation of the foundation monitoring points mentioned in steps 3.2 and 3.4 specifically includes: calculating the horizontal displacement vector and calculating the vertical displacement vector of the slope monitoring points; and calculating the horizontal displacement vector of the monitoring points within the slope.

[0104] The calculated deformation of the foundation monitoring point is extracted from the finite element model.

[0105] The minimum deviation mentioned in step 3.5 refers to the minimum deviation function; the deviation function includes the slope monitoring point deviation function and the slope intra-monitoring point deviation function; the slope monitoring point deviation function is equal to the sum of the horizontal displacement vector deviation and the vertical displacement vector deviation of all slope monitoring points; the slope intra-monitoring point deviation function is equal to the sum of the horizontal displacement vector deviation of all intra-slope monitoring points.

[0106] Let Xmon be the magnitude of the X component of the monitored horizontal displacement vector, Ymon be the magnitude of the monitored horizontal displacement vector, and Zmon be the magnitude of the monitored vertical displacement vector. Let Xcal1 be the initially calculated magnitude of the X component of the horizontal displacement vector, Ycal1 be the initially calculated magnitude of the Y component of the horizontal displacement vector, and Zcal1 be the initially calculated magnitude of the vertical displacement vector. Let Xcal2 be the magnitude of the slidingly calculated magnitude of the X component of the horizontal displacement vector, Ycal2 be the magnitude of the slidingly calculated magnitude of the horizontal displacement vector, and Zcal2 be the magnitude of the slidingly calculated vertical displacement vector. The sum of the deviations of the horizontal and vertical displacement vectors at the slope monitoring points is equal to (Xmon - (Xcal2 - Xcal1)). 2 +(Ymon-(Ycal2-Ycal1)) 2 +(Zmon-(Zcal2-Zcal1)) 2 The horizontal displacement vector deviation of the monitoring point within the slope is equal to (Xmon - (Xcal2 - Xcal1)). 2 +(Ymon-(Ycal2-Ycal1)) 2 .

[0107] Step 4: Use the strength reduction method to reduce the inverted cohesion and inverted internal friction angle of the potential sliding surface 5 to determine the safety factor of the slope.

[0108] The strength reduction method is a common method for calculating the safety factor in finite element analysis (FEM). It involves continuously reducing the inverted cohesion and inverted internal friction angle of the potential sliding surface (5) until the FEM calculation results indicate slope instability. At this point, 1 divided by the reduction factor gives the safety factor. For example, if the inverted cohesion and inverted internal friction angle are reduced by a factor of 0.8, and the FEM calculation results indicate instability, then 1 / 0.8 is the safety factor.

[0109] Step 5: Determine the slope sliding direction based on the horizontal displacement direction of the foundation monitoring points and the potential unstable slope body.

[0110] Step 5 describes determining the slope sliding direction based on the horizontal displacement direction of the foundation monitoring points and the potential unstable slope mass, as follows:

[0111] Step 5.1: Use multiple sets of cutting surfaces with a spacing of a in the X, Y and Z directions to divide the potentially unstable slope body into multiple segments 10.

[0112] The segment 10 satisfies the condition that each segment 10 can be completely enclosed by a cube of size a×a×a.

[0113] Step 5.2: Determine the direction of the horizontal displacement of each foundation monitoring point as the direction of the monitored horizontal displacement vector.

[0114] Step 5.3: Calculate the horizontal displacement direction of each segment 10. Specifically, based on the spatial location and horizontal movement direction of the foundation monitoring point, the horizontal displacement direction of each segment 10 is determined by inverse distance interpolation.

[0115] In the inverse distance interpolation, the distance between the segment 10 and the foundation monitoring point is the spatial distance between the centroid of the segment 10 and the foundation monitoring point.

[0116] The inverse distance interpolation is a spatial interpolation method. For example, to obtain the horizontal displacement direction of a segment 10, first obtain the horizontal displacement directions (represented as azimuth angles γ1, γ2, ..., γn) of n foundation monitoring points within a certain range of the segment 10, and then calculate the distance (represented as distances L1, L2, ..., Ln) between the centroid of the segment 10 and each foundation monitoring point. The horizontal displacement direction of the segment is (1 / L1×γ1) + (1 / L1×γ2) + ... + (1 / Ln×γn).

[0117] The horizontal displacement direction of each segment 10 is a vector with a modulus of 1.

[0118] Step 5.4: Calculate the volume of all segments 10, multiply the volume of segment 10 by its horizontal displacement direction (vector), and then sum all the vectors. The sum of the vectors is the horizontal sliding direction of the potential unstable slope.

[0119] Step 6: Display the slope, potentially unstable slope and its sliding direction through a visualization platform, and display the volume of the potentially unstable slope and the safety factor of the slope through text.

[0120] Both the monitored horizontal displacement vector and the calculated horizontal displacement vector are horizontal displacement vectors; both the monitored vertical displacement vector and the calculated vertical displacement vector are vertical displacement vectors; both the horizontal and vertical displacement vectors are located in a spatial rectangular coordinate system with the horizontal axis as the X-axis, the vertical axis as the Y-axis, and the vertical axis as the Z-axis; the vertical displacement vector is parallel to the Z-axis; the horizontal displacement vector is parallel to the plane formed by the X-axis and the Y-axis; the horizontal displacement vector can be decomposed into two components parallel to the X-axis and the Y-axis respectively, denoted as the X component and the Y component of the horizontal displacement vector; the magnitude of the vertical displacement vector (or the X component of the horizontal displacement vector, or the Y component of the horizontal displacement vector) is equal to the magnitude of the vertical displacement vector (or the X component of the horizontal displacement vector, or the Y component of the horizontal displacement vector) multiplied by a positive or negative one, specifically: if the vertical displacement vector (or the X component of the horizontal displacement vector, or the Y component of the horizontal displacement vector) points in the same direction as the Z-axis (or the X-axis or the Y-axis), it is multiplied by a positive one; otherwise, it is multiplied by a negative one.

[0121] The magnitude of the horizontal displacement monitoring surface component is equal to the modulus of the horizontal displacement monitoring surface component multiplied by a positive or negative one. Specifically, if the direction of the horizontal displacement monitoring surface component is consistent with the slope orientation, it is multiplied by a positive one; otherwise, it is multiplied by a negative one. The method for determining the magnitude of the horizontal component of the similar ellipsoid tangent vector 9 is the same as that for the horizontal displacement monitoring surface component, and the method for determining the magnitude of the vertical component of the similar ellipsoid tangent vector 9 is the same as that for the vertical displacement vector.

[0122] This invention uses the distribution of deformation foundation monitoring points and deformation fitting to determine the potential sliding surface; it establishes a three-dimensional finite element model of the slope and determines the cohesion and internal friction angle of the potential sliding surface through inversion; it uses the strength reduction method to reduce the inverted cohesion and internal friction angle of the sliding surface to determine the slope's safety factor; it determines the slope's sliding direction based on the horizontal displacement direction of the foundation monitoring points and the potential unstable slope body; finally, it displays the slope, the potential unstable slope body, and their sliding direction through a visualization platform, showing the volume of the potential unstable slope body and the slope's safety factor. This invention determines the three-dimensional sliding surface of the slope through surface fitting, and then calculates the slope's safety factor through parameter inversion and the strength reduction method, achieving an early warning description of slope instability morphology, including characteristics such as instability volume and direction.

[0123] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A slope instability assessment method based on deformation monitoring data, characterized in that, Includes the following steps: Step 1: Obtain topographic data, stratigraphic data, spatial coordinates of foundation monitoring points, deformation monitoring data of foundation monitoring points, and physical parameters of rock / soil in the surrounding area of ​​the slope; The foundation monitoring points include slope monitoring points (2) and in-slope monitoring points (6); the foundation monitoring points are distributed in multiple monitoring sections (4); the monitoring sections (4) are parallel to the slope orientation (1), and each monitoring section (4) contains slope monitoring points (2) and in-slope monitoring points (6). The deformation monitoring data specifically includes: the monitoring horizontal displacement vector and the monitoring vertical displacement vector of the slope monitoring point (2); the monitoring horizontal displacement vector of the monitoring point (6) inside the slope; the deformation monitoring data of the monitoring point (6) inside the slope is obtained by the inclinometer (3), the inclinometer (3) is installed in the inclinometer hole, and at least one inclinometer (3) is installed in the same inclinometer hole. The physical parameters of the rock / soil include unit weight, elastic modulus, Poisson's ratio, cohesion, and internal friction angle; Step 2: Obtain the spatial coordinates and deformation monitoring data of foundation monitoring points that are deformed in the same time period. The foundation monitoring points that are deformed are called deformed foundation monitoring points, which can be further subdivided into deformed slope monitoring points and deformed slope monitoring points. And based on the distribution of the deformation foundation monitoring points and the cumulative deformation, the potential sliding surface is fitted (5); Step 3: Establish a three-dimensional finite element model of the slope, and determine the inversion cohesion and inversion internal friction angle of the potential sliding surface (5) through inversion; Step 4: Use the strength reduction method to reduce the inverted cohesion and inverted internal friction angle of the potential sliding surface (5) to determine the safety factor of the slope; Step 5: Determine the slope sliding direction based on the horizontal displacement direction of the foundation monitoring points and the potential unstable slope body; Step 6: Display the slope, potentially unstable slope body and its sliding direction through a visualization platform, and show the volume of the potentially unstable slope body and the safety factor of the slope; In step 2, the process of fitting the potential sliding surface (5) based on the distribution of deformation foundation monitoring points and cumulative deformation is as follows: Step 2.1: Obtain the monitoring sections (4) of all foundation monitoring points with deformation, which are called deformation monitoring sections; Step 2.2: Obtain all foundation monitoring points within the deformation monitoring section, and determine multiple constraint line segments (7) based on the deformation foundation monitoring points and the remaining foundation monitoring points. Step 2.3: Fit an ellipsoid that minimizes the objective function in space as a potential sliding surface (5); The objective function is equal to the sum of the constraint penalty function and the horizontal settlement ratio function; The multiple constraint line segments (7) are specifically formed by taking the highest elevation deformation slope monitoring point in the same monitoring section as the endpoint and finding the nearest non-deformation slope monitoring point in the opposite direction of the slope orientation as the other endpoint to form a constraint line segment (7), which is called the upper constraint line segment. Within the same monitoring section, take the monitoring point of the deformed slope with the lowest elevation as the endpoint, and find the nearest non-deformed slope monitoring point in the direction of the slope as the other endpoint to form a constraint line segment (7), which is called the lower constraint line segment; within the same inclinometer hole of the same monitoring section, connect the monitoring point in the deformed slope with the nearest non-deformed slope monitoring point to form a constraint line segment (7), which is called the inner constraint line segment; In step 2.3, the constraint penalty function is equal to the sum of the squares of the lengths of the extended intersecting segments of all constraint line segments (7) multiplied by the coefficient α; The length of the extended intersection segment of the constraint line segment is as follows: if the constraint line segment (7) intersects with the ellipsoid, the length of the extended intersection segment of the constraint line segment is zero; if the constraint line segment (7) does not intersect with the ellipsoid, the length of the extended intersection segment of the constraint line segment is determined by judgment extension. The determination of the length of the intersection segment of the constraint line segment extension is as follows: Starting from the two endpoints of the constraint line segment (7), extend outward to find the intersection point with the ellipsoid; determine a true intersection point according to the different constraint line segments (7); if a true intersection point exists, the distance between the true intersection point and the midpoint of the constraint line segment minus half the length of the constraint line segment and then divided by one meter is taken as the length of the intersection segment of the constraint line segment extension; if the constraint line segment (7) is the upper constraint line segment, the intersection point with the largest elevation is taken as the true intersection point; otherwise, the intersection point with the smallest elevation is taken as the true intersection point; if a true intersection point does not exist, the length of the intersection segment of the constraint line segment extension is β. The horizontal settlement ratio function is as follows: Step 2.3.1: Obtain the horizontal displacement monitoring surface component and the vertical displacement vector of the monitoring point located inside the ellipsoidal deformation slope, and solve the ratio of the magnitude of the horizontal displacement monitoring surface component to the magnitude of the vertical displacement vector, denoted as the monitoring horizontal settlement ratio; The horizontal displacement monitoring surface component refers to the component of the monitored horizontal displacement vector of the deformation slope monitoring point within the monitoring section. Step 2.3.2: Solve for the similar ellipsoidal tangent vector (9) of each deformation slope monitoring point located inside the ellipsoid in the monitoring section (4), and solve for the ratio of the horizontal component to the vertical component of the similar ellipsoidal tangent vector (9), which is denoted as the calculated horizontal settlement ratio; The specific solution process for the tangent vector (9) of the similar ellipsoid is as follows: Step 2.3.2a: Construct a similar ellipsoid (8) in space that is similar to the potential sliding surface (5). The similar ellipsoid satisfies two requirements: (1) The monitoring point of the deformed slope is located on the similar ellipsoid (8); (2) The similar ellipsoid (8) is obtained by keeping the ellipsoid center of the potential sliding surface (5) unchanged and enlarging or reducing it by a certain proportion. Step 2.3.2b: Intersect the monitoring section (4) with the similar ellipsoid (8) to obtain a two-dimensional closed curve, and solve for a tangent vector of the deformed slope monitoring point in the two-dimensional closed curve as the similar ellipsoid tangent vector (9) of the deformed slope monitoring point in the monitoring section (4); the horizontal component of the similar ellipsoid tangent vector (9) is consistent with the slope orientation; Step 2.3.3: Solve for the sum of squares of the differences between the monitored horizontal settlement ratio and the calculated horizontal settlement ratio at all deformation slope monitoring points, and use this as the horizontal settlement ratio function; In step 5, the slope sliding direction is determined based on the horizontal displacement direction of the foundation monitoring points and the potential unstable slope body, as detailed below: Step 5.1: Use multiple sets of cutting surfaces with a spacing of a in the X, Y and Z directions to divide the potentially unstable slope body into multiple segments (10). Step 5.2: Determine the direction of the horizontal displacement of each foundation monitoring point as the direction of the monitored horizontal displacement vector; Step 5.3: Calculate the horizontal displacement direction of each segment (10). Specifically, based on the spatial location and horizontal movement direction of the foundation monitoring point, the horizontal displacement direction of each segment (10) is determined by inverse distance interpolation. The horizontal displacement direction of each segment (10) is a vector with a magnitude of 1; Step 5.4: Calculate the volume of all segments (10), multiply the volume of each segment (10) by its horizontal displacement direction, and then sum all vectors. The sum of these vectors is the horizontal sliding direction of the potentially unstable slope.

2. The slope instability assessment method based on deformation monitoring data according to claim 1, characterized in that, In step 3, the inversion determines the inversion cohesion and inversion internal friction angle of the potential sliding surface (5), as follows: Step 3.1: Take the physical parameters of the potential sliding surface (5) to be the same as the physical parameters of the potential unstable slope, and achieve equilibrium under self-weight stress; The potentially unstable slope body is the body obtained by cutting the slope with the potential sliding surface (5); Step 3.2: Extract the calculated deformation of each foundation monitoring point from Step 3.1, and record it as the initial calculated deformation; The initial calculated deformation data are as follows: the initial calculated horizontal displacement vector and the initial calculated vertical displacement vector of the slope monitoring point (2); the initial calculated horizontal displacement vector of the monitoring point (6) inside the slope; Step 3.3: Obtain the cohesion c0 and internal friction angle ψ0 of the potential unstable slope; take positive integers m and n, and preset m-1 cohesion and n-1 internal friction angles according to (c0 / m, c0×2 / m, ..., c0×(m-1) / m) and (ψ0 / n, ψ0×2 / n, ..., ψ0×(n-1) / n) respectively, and combine the preset cohesion and internal friction angles to form (m-1)×(n-1) combinations of preset cohesion and internal friction angles; Step 3.4: Replace the cohesion and internal friction angle of the potential sliding surface (5) with different preset cohesion and internal friction angle combinations in turn, and continue to calculate based on the results of step 3.

1. Extract the calculated deformation of each foundation monitoring point in the calculation results and record it as the sliding calculated deformation. The specific sliding deformation data are: the sliding calculation horizontal displacement vector and sliding calculation vertical displacement vector of the slope monitoring point (2); and the sliding calculation horizontal displacement vector of the monitoring point (6) inside the slope. Step 3.5: Compare the difference between all the sliding calculated deformation and the initial calculated deformation with the deformation monitoring data of the foundation monitoring points, and select the set of preset cohesion and internal friction angle with the smallest deviation as the inversion cohesion and inversion internal friction angle of the potential sliding surface (5).

3. The slope instability assessment method based on deformation monitoring data according to claim 2, characterized in that, In steps 3.2 and 3.4, the calculation of deformation of the foundation monitoring points specifically includes: calculating the horizontal displacement vector and calculating the vertical displacement vector of the slope monitoring points; and calculating the horizontal displacement vector of the monitoring points within the slope.

4. The slope instability assessment method based on deformation monitoring data according to claim 2, characterized in that, In step 3.5, the minimum deviation refers to the minimum deviation function; the deviation function includes the slope monitoring point deviation function and the slope intra-monitoring point deviation function; the slope monitoring point deviation function is equal to the sum of the horizontal displacement vector deviations and vertical displacement vector deviations of all slope monitoring points; the slope intra-monitoring point deviation function is equal to the sum of the horizontal displacement vector deviations of all intra-slope monitoring points. Let Xmon be the magnitude of the X component of the monitored horizontal displacement vector, Ymon be the magnitude of the monitored horizontal displacement vector, and Zmon be the magnitude of the monitored vertical displacement vector. Let Xcal1 be the magnitude of the initially calculated X component of the horizontal displacement vector, Ycal1 be the magnitude of the initially calculated Y component of the horizontal displacement vector, and Zcal1 be the magnitude of the initially calculated vertical displacement vector. Let Xcal2 be the magnitude of the sliding calculated X component of the horizontal displacement vector, Ycal2 be the magnitude of the sliding calculated Y component of the horizontal displacement vector, and Zcal2 be the magnitude of the sliding calculated vertical displacement vector. The sum of the deviations of the horizontal and vertical displacement vectors at the slope monitoring points is equal to (Xmon - (Xcal2 - Xcal1)). 2 +(Ymon-(Ycal2- Ycal1)) 2 +(Zmon-(Zcal2-Zcal1)) 2 The horizontal displacement vector deviation of the monitoring point within the slope is equal to (Xmon - (Xcal2 - Xcal1)). 2 +(Ymon-(Ycal2-Ycal1)) 2 .

5. The slope instability assessment method based on deformation monitoring data according to claim 1, characterized in that, In step 4, the strength reduction method is used to calculate the safety factor of the slope, specifically as follows: The inversion cohesion and inversion internal friction angle of the potential sliding surface (5) are continuously reduced until the finite element calculation results show that the slope is unstable. At this time, 1 is divided by the reduction factor to obtain the safety factor of the slope.

6. A computer program product, characterized in that, It includes a computer program / instruction that, when executed by a processor, implements the slope instability assessment method based on deformation monitoring data as described in any one of claims 1 to 5.

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