Slope instability assessment method based on deformation monitoring data

Abstract

The invention discloses a slope instability assessment method based on deformation monitoring data, and relates to the field of slope engineering monitoring data analysis, and the method comprises the steps: obtaining the related data of the landform, stratum, foundation monitoring points and the like of the surrounding range of a slope; fitting a potential sliding surface according to the distribution and deformation of the deformation foundation monitoring points; establishing a three-dimensional finite element model of the side slope, and determining the cohesive force and the internal friction angle of a potential sliding surface through inversion; carrying out reduction calculation on the inversion cohesive force and the internal friction angle of the sliding surface by adopting a strength reduction method, and determining the safety coefficient of the slope; determining the sliding direction of the side slope according to the horizontal displacement direction of the foundation monitoring point and the potential unstable slope body; and finally, the side slope, the potential unstable slope body and the sliding direction of the potential unstable slope body are displayed through a visual platform, and the volume of the potential unstable slope body and the safety coefficient of the side slope are displayed through characters. According to the method, the three-dimensional sliding surface of the side slope is determined through curved surface fitting, the safety coefficient of the side slope is calculated through parameter inversion and a strength reduction method, and early warning description of the side slope instability form including the instability volume, the instability direction and other characteristics is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of engineering monitoring, and in particular to a slope instability assessment method based on deformation monitoring data. Background Art

[0002] The technology of slope engineering monitoring is complicated, and the most direct factor that reflects slope instability is deformation. There are two main types of existing slope deformation monitoring methods, one is foundation deformation monitoring, and the other is air-based deformation monitoring. Among them, foundation deformation monitoring mainly uses deformation monitoring sensors installed on the slope surface or inside the slope to capture slope deformation; air-based deformation monitoring mainly uses drones or satellite-mounted radars to regularly scan slopes to capture slope deformation. Foundation deformation monitoring is characterized by point-like and high frequency; air-based deformation monitoring is characterized by surface-like and low frequency.

[0003] Foundation deformation monitoring should be characterized by high frequency and strong timeliness. Therefore, foundation deformation monitoring is often the main method in slope monitoring. In the analysis of foundation deformation monitoring data, technicians usually use threshold warning, such as the slope monitoring and early warning method disclosed in Chinese invention patent CN117195610A, which determines the stability warning value of any monitoring point on the slope to be monitored through multiple slope surfaces, and issues an early warning to the monitoring point when the stability warning value is greater than or equal to the preset threshold. This early warning method can only simply reflect the stability state of the slope, and cannot reflect the volume and direction of the potential instability and sliding of the slope. Summary of the invention

[0004] In order to overcome the defects in the above-mentioned prior art, the present invention provides a slope instability assessment method based on deformation monitoring data, which evaluates the potential instability form of the slope by fitting a three-dimensional sliding surface, and determines the possibility of slope instability by inversion and strength reduction method.

[0005] To achieve the above object, the present invention adopts the following technical solutions, including:

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

[0007] Step 1: Obtain terrain data, stratigraphic data, spatial coordinates of foundation monitoring points, deformation monitoring data of foundation monitoring points, and physical parameters of rock / soil around the slope;

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

[0009] The deformation monitoring data specifically includes: monitoring horizontal displacement vector and monitoring vertical displacement vector of the slope monitoring point; monitoring 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, the inclinometer 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 mass include density, elastic modulus, Poisson's ratio, cohesion and internal friction angle;

[0011] Step 2: Obtain the spatial coordinates and deformation monitoring data of the foundation monitoring points with deformation in the same time period. The foundation monitoring points with deformation are called deformed foundation monitoring points, which can be specifically divided into deformed slope monitoring points and deformed slope monitoring points; and fit the potential sliding surface according to the distribution and cumulative deformation of the deformed foundation monitoring points;

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

[0013] Step 4: Use the strength reduction method to reduce the inverse cohesion and inverse 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 point and the potential unstable slope;

[0015] Step 6: The slope, potential unstable slope and its sliding direction are displayed through the visualization platform, and the volume of the potential unstable slope and the safety factor of the slope are displayed.

[0016] Preferably, in step 2, the potential sliding surface is fitted according to the distribution and cumulative deformation of the deformed foundation monitoring points, specifically as follows:

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

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

[0019] Step 2.3: Fit an ellipsoid with the minimum objective function in space as the 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 line segments are specifically: in the same monitoring section, the highest deformed slope monitoring point is used as an endpoint, and a nearest non-deformed slope monitoring point is found in the opposite direction of the slope as the other endpoint to form a constraint line segment, which is called an upper constraint line segment; in the same monitoring section, the lowest deformed slope monitoring point is used as an endpoint, and a nearest non-deformed slope monitoring point is found in the direction of the slope as the other endpoint to form a constraint line segment, which is called a lower constraint line segment; in the same inclinometer hole in the same monitoring section, the deformed slope monitoring point is connected with the nearest non-deformed slope monitoring point to form a constraint line segment, which is called an inner constraint line segment;

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

[0023] The length of the constrained line segment extending the intersection segment is specifically: if the constrained line segment and the ellipsoidal surface have an intersection point, the length of the constrained line segment extending the intersection segment is zero; if the constrained line segment and the ellipsoidal surface do not have an intersection point, the length of the constrained line segment extending the intersection segment is determined by judging the extension;

[0024] The determination of the extension and determination of the length of the extended intersection segment of the constraint line segment is as follows: starting from the two end points of the constraint line segment, extending outward to obtain the intersection point with the ellipsoid; determining a true intersection point according to different constraint line segments; if the true intersection point exists, the distance between the true intersection point and the midpoint of the constraint line segment minus half of the length of the constraint line segment divided by one meter is used as the length of the extended intersection segment of the constraint line segment; wherein, if the constraint line segment is an 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 the true intersection point does not exist, the length of the extended intersection segment of the 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 monitoring vertical displacement vector of the monitoring point on the deformed slope inside the ellipsoid, and solve the ratio of the horizontal displacement monitoring surface component to the monitoring vertical displacement vector, which is recorded as the monitoring horizontal settlement ratio;

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

[0028] Step 2.3.2: Calculate the similar ellipsoid tangent vector of each deformed slope monitoring point located inside the ellipsoid within the monitoring section, and calculate the ratio of the horizontal component to the vertical component of the similar ellipsoid tangent vector, which is recorded as the calculated horizontal settlement ratio;

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

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

[0031] Step 2.3.2b: The monitoring section is intersected with the similar ellipsoid to obtain a two-dimensional closed curve, and a tangent vector of the deformed slope monitoring point in the two-dimensional closed curve is solved 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 direction;

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

[0033] Preferably, in step 3, the inversion determines the inversion cohesion and the 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 potential unstable slope body is a body obtained by cutting the slope with a potential sliding surface;

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

[0037] The initial calculated deformation data specifically include: the initial calculated horizontal displacement vector and the initial calculated vertical displacement vector of the monitoring point on the slope surface; the initial calculated horizontal displacement vector of the monitoring point inside 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, preset m-1 cohesions 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 cohesions and internal friction angles to form (m-1)×(n-1) combinations of preset cohesions and internal friction angles;

[0039] Step 3.4: Replace the cohesion and internal friction angle of the potential sliding surface with different preset cohesion and internal friction angle combinations in turn, and continue the calculation 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 calculation deformation;

[0040] The sliding calculation deformation data specifically include: sliding calculation horizontal displacement vector and sliding calculation vertical displacement vector of the monitoring point on the slope surface; sliding calculation horizontal displacement vector of the monitoring point inside the slope;

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

[0042] Preferably, in steps 3.2 and 3.4, the calculated deformation of the foundation monitoring points specifically includes: calculating horizontal displacement vectors and calculating vertical displacement vectors of the slope monitoring points; and calculating horizontal displacement vectors 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 monitoring point deviation function; the slope monitoring point deviation function is equal to the sum of the sum of the horizontal displacement vector deviations and the vertical displacement vector deviations of all slope monitoring points; the slope monitoring point deviation function is equal to the sum of the horizontal displacement vector deviations of all slope monitoring points;

[0044] The size of the X component of the monitored horizontal displacement vector is Xmon, the size of the Y component of the monitored horizontal displacement vector is Ymon, the size of the monitored vertical displacement vector is Zmon, the size of the X component of the initially calculated horizontal displacement vector is Xcal1, the size of the Y component of the initially calculated horizontal displacement vector is Ycal1, the size of the initially calculated vertical displacement vector is Zcal1, the size of the X component of the sliding calculated horizontal displacement vector is Xcal2, the size of the Y component of the sliding calculated horizontal displacement vector is Ycal2, the size of the sliding calculated vertical displacement vector is Zcal2, and the sum of the horizontal displacement vector deviation and the vertical displacement vector deviation of the slope monitoring point is equal to (Xmon-(Xcal2-Xcal1)) 2 +(Ymon-(Ycal2-Ycal1)) 2 +(Zmon-(Zcal2-Zcal1)) 2 ; The horizontal displacement vector deviation of the monitoring point in the slope is equal to (Xmon-(Xcal2-Xcal1)) 2 +(Ymon-(Ycal2-Ycal1)) 2 .

[0045] Preferably, in step 5, the slope sliding direction is determined according to the horizontal displacement direction of the foundation monitoring point and the potential unstable slope, as follows:

[0046] Step 5.1: Use multiple sets of cutting planes with a spacing of a in the X, Y and Z directions to segment the potential unstable slope to form multiple segmented bodies;

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

[0048] Step 5.3: Calculate the horizontal displacement direction of each segmented body, specifically: take the spatial position and horizontal movement direction of the foundation monitoring point as basic data, and use inverse distance interpolation to determine the horizontal displacement direction of each segmented body;

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

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

[0051] Preferably, in step 4, the safety factor of the slope is calculated using the strength reduction method, specifically:

[0052] The inverse cohesion and inverse 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 time, 1 is divided by the reduction coefficient to obtain the safety factor of the slope.

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

[0054] The advantages of the present invention are:

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

[0056] (2) Through inversion, the physical parameters of the slope sliding surface can be calculated more accurately, and then the safety factor can be calculated through the strength reduction method, which helps technicians to accurately understand the stability 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 facilitates the assessment of the objects that are harmed downstream of the slope.

[0058] (4) The present invention determines the three-dimensional sliding surface of the slope by surface fitting, and then calculates the safety factor of the slope by parameter inversion and strength reduction method, thereby realizing an early warning description of the instability morphology of the slope including characteristics such as instability volume and direction. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0060] Figure 2 Arrange a bird's-eye view of the slope ground-level monitoring points.

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

[0062] Figure 4 Schematic diagram of the segmentation of potential unstable slope within the monitoring section.

[0063] The reference numerals are as follows:

[0064] 1. Slope orientation; 2. Slope monitoring points; 3. Inclinometer; 4. Monitoring section; 5. Potential sliding surface; 6. Monitoring points within the slope; 7. Constraint line segment; 8. Similar ellipsoid surface; 9. Similar ellipsoid tangent vector; 10. Segmentation body. DETAILED DESCRIPTION

[0065] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

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

[0067] Step 1: Obtain terrain data, stratigraphic data, spatial coordinates of foundation monitoring points, deformation monitoring data of foundation monitoring points, and physical parameters of rock / soil around the slope.

[0068] The slope refers to a slope whose potentially unstable slope body is a quasi-homogeneous rock / soil body; the quasi-homogeneous rock / soil body means that the rock / soil body is calculated using the same set of physical parameters.

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

[0070] The deformation monitoring data are specifically as follows: the deformation monitoring data of the slope monitoring point 2 is obtained through a GNSS (Global Navigation Satellite System) receiver, including monitoring the horizontal displacement vector and monitoring the vertical displacement vector; the deformation monitoring data of the monitoring point 6 inside the slope is obtained through an inclinometer 3, including monitoring the 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 mass include density, elastic modulus, Poisson's ratio, cohesion and internal friction angle.

[0072] Step 2: Obtain the spatial coordinates and deformation monitoring data of the foundation monitoring points with deformation in the same time period. The foundation monitoring points with deformation are called deformed foundation monitoring points, which can be specifically divided into deformed slope monitoring points and deformed slope monitoring points. The potential sliding surface 5 is fitted according to the distribution and cumulative deformation of the deformed foundation monitoring points.

[0073] Step 2 is to fit the potential sliding surface 5 according to the distribution and cumulative deformation of the deformed foundation monitoring points, as follows:

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

[0075] Step 2.2: Obtain all foundation monitoring points in the deformation monitoring section, and determine multiple constraint line segments 7 according to the deformed foundation monitoring points and the remaining foundation monitoring points.

[0076] Step 2.2 describes determining multiple constraint line segments 7 based on the deformed foundation monitoring point and the remaining foundation monitoring points, specifically: within the same monitoring section, the deformed slope monitoring point with the highest elevation is used as the endpoint, and a nearest non-deformed slope monitoring point is found in the opposite direction of the slope as the other endpoint to form a constraint line segment 7, which is called an upper constraint line segment; within the same monitoring section, the deformed slope monitoring point with the lowest elevation is used as the endpoint, and a nearest non-deformed slope monitoring point is found in the direction of the slope as the other endpoint to form a constraint line segment 7, which is called a lower constraint line segment; within the same inclinometer hole 3 in the same monitoring section, the deformed slope monitoring point is connected with the nearest non-deformed slope monitoring point to form a constraint line segment 7, which is called an inner constraint line segment.

[0077] Step 2.3: Fit an ellipsoid with the minimum 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 square sum of the lengths of the extended intersection 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 specifically: if the constraint line segment 7 has an intersection point with the ellipsoid surface, the length of the extended intersection segment of the constraint line segment is zero; if the constraint line segment 7 does not have an intersection point with the ellipsoid surface, the length of the extended intersection segment of the constraint line segment is determined by judging the extension.

[0080] The determination of the extension and determination of the length of the intersecting segment of the constrained line segment is as follows: starting from the two end points of the constrained line segment 7, extending outward to obtain the intersection with the ellipsoid; determining a true intersection point according to the difference of the constrained line segment 7; the distance between the true intersection point and the midpoint of the constrained line segment minus half of the length of the constrained line segment divided by one meter is used as the length of the intersecting segment of the constrained line segment.

[0081] The determining of a true intersection point is specifically as follows: if the constraint line segment 7 is an 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 an artificially set real number greater than 0.

[0083] Furthermore, if the true intersection point does not exist, the length of the extended intersection segment of the constraint line segment is β; 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 monitoring vertical displacement vector of the deformation slope monitoring point inside the ellipsoid, and solve the ratio of the horizontal displacement monitoring surface component to the monitoring vertical displacement vector, which is recorded as the monitoring horizontal settlement ratio.

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

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

[0088] The similar ellipsoid tangent vector 9 of the deformed slope monitoring point in the monitoring section described in step 2.3.2 is specifically solved as follows:

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

[0090] Step 2.3.2b: Intersect the monitoring section 4 with the similar ellipsoid surface 8 to obtain a two-dimensional closed curve, and solve 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 direction 1.

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

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

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

[0096] The potential unstable slope body is a body obtained by cutting the slope with 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 specifically: the initial calculated horizontal displacement vector and the initial calculated vertical displacement vector of the slope monitoring point 2; and the initial calculated horizontal displacement vector of the monitoring point 6 inside the slope.

[0099] Step 3.3: Obtain the cohesion c0 and internal friction angle ψ0 of the potentially unstable slope; take positive integers m and n, preset m-1 cohesions 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 cohesions and internal friction angles to form (m-1)×(n-1) combinations of preset cohesions 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 the calculation 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 calculation deformation.

[0101] The sliding calculation deformation data specifically include: the sliding calculation horizontal displacement vector and the sliding calculation vertical displacement vector of the slope monitoring point 2; and the sliding calculation horizontal displacement vector of the slope monitoring point 6.

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

[0103] The calculated deformation of the foundation monitoring points described 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 in step 3.5 means that the deviation function is minimum; the deviation function includes the slope monitoring point deviation function and the slope monitoring point deviation function; the slope monitoring point deviation function is equal to the sum of the horizontal displacement vector deviations and the vertical displacement vector deviations of all slope monitoring points; the slope monitoring point deviation function is equal to the sum of the horizontal displacement vector deviations of all slope monitoring points.

[0106] The size of the X component of the monitored horizontal displacement vector is Xmon, the size of the Y component of the monitored horizontal displacement vector is Ymon, the size of the monitored vertical displacement vector is Zmon, the size of the X component of the initially calculated horizontal displacement vector is Xcal1, the size of the Y component of the initially calculated horizontal displacement vector is Ycal1, the size of the initially calculated vertical displacement vector is Zcal1, the size of the X component of the sliding calculated horizontal displacement vector is Xcal2, the size of the Y component of the sliding calculated horizontal displacement vector is Ycal2, the size of the sliding calculated vertical displacement vector is Zcal2, and the sum of the horizontal displacement vector deviation and the vertical displacement vector deviation of the slope monitoring point is equal to (Xmon-(Xcal2-Xcal1)) 2 +(Ymon-(Ycal2-Ycal1)) 2 +(Zmon-(Zcal2-Zcal1)) 2 ; The horizontal displacement vector deviation of the monitoring point in the slope is equal to (Xmon-(Xcal2-Xcal1)) 2 +(Ymon-(Ycal2-Ycal1)) 2 .

[0107] Step 4: Use the strength reduction method to reduce the inverse cohesion and inverse 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 calculation method in finite element to calculate the safety factor. It continuously reduces the inverse cohesion and inverse internal friction angle of the potential sliding surface 5 until the finite element calculation results show that the slope is unstable. At this time, the safety factor is 1 divided by the reduction factor. For example, when the inverse cohesion and inverse internal friction angle are reduced by 0.8 times, the finite element calculation results show 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 point and the potential unstable slope.

[0110] Step 5 determines the slope sliding direction according to the horizontal displacement direction of the foundation monitoring point and the potential unstable slope, as follows:

[0111] Step 5.1: Use multiple sets of cutting planes with a spacing of a in the X, Y and Z directions to segment the potential unstable slope to form multiple segmented bodies 10.

[0112] The split bodies 10 satisfy the requirement that each split body 10 can be completely enclosed by a cube with a size of a×a×a.

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

[0114] Step 5.3: Calculate the horizontal displacement direction of each segment 10, specifically: take the spatial position and horizontal movement direction of the foundation monitoring point as basic data, and use inverse distance interpolation to determine the horizontal displacement direction of each segment 10.

[0115] The distance between the segmented body 10 and the ground monitoring point in the inverse distance interpolation is the spatial distance between the centroid of the segmented body 10 and the ground monitoring point.

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

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

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

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

[0120] The monitored horizontal displacement vector and the calculated horizontal displacement vector are both horizontal displacement vectors; the monitored vertical displacement vector and the calculated vertical displacement vector are both vertical displacement vectors; the horizontal displacement vector and the vertical displacement vector are both located in a spatial rectangular coordinate system with the horizontal axis being the X axis, the vertical axis being the Y axis, and the vertical axis being 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, recorded as the X component of the horizontal displacement vector 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 modulus 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 positive one 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 positive one; otherwise, it is multiplied by 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 positive one or negative one, specifically: if the direction of the horizontal displacement monitoring surface component is consistent with the direction of the slope, it is multiplied by positive one; otherwise, it is multiplied by negative one; the method for determining the magnitude of the horizontal component of the similar ellipsoid tangent vector 9 is the same as that of 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 of the vertical displacement vector.

[0122] The present invention fits the potential sliding surface according to the distribution and deformation of the deformed foundation monitoring points; establishes a three-dimensional finite element model of the slope, and determines the cohesion and internal friction angle of the potential sliding surface by inversion; uses the strength reduction method to reduce the inverted cohesion and internal friction angle of the sliding surface to determine the safety factor of the slope; determines the sliding direction of the slope according to the horizontal displacement direction of the foundation monitoring points and the potential unstable slope; finally, the slope, the potential unstable slope and its sliding direction are displayed through a visualization platform, and the volume of the potential unstable slope and the safety factor of the slope are displayed. The present invention determines the three-dimensional sliding surface of the slope by surface fitting, and then calculates the safety factor of the slope by parameter inversion and strength reduction method, thereby realizing the early warning description of the instability morphology of the slope including the characteristics of the instability volume, direction, etc.

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

Claims

1. A slope instability assessment method based on deformation monitoring data, characterized in that: The following steps are involved: Step 1: Obtain terrain data, stratigraphic data, spatial coordinates of foundation monitoring points, deformation monitoring data of foundation monitoring points, and physical parameters of rock / soil around the slope; The foundation monitoring points include slope surface monitoring points (2) and slope in-slope monitoring points (6); the foundation monitoring points are distributed in a plurality of monitoring sections (4); the monitoring sections (4) are parallel to the slope direction (1), and each monitoring section (4) contains a slope surface monitoring point (2) and a slope in-slope monitoring point (6); The deformation monitoring data specifically include: a monitoring horizontal displacement vector and a monitoring vertical displacement vector of a slope monitoring point (2); a monitoring horizontal displacement vector of a monitoring point (6) within the slope; the deformation monitoring data of the monitoring point (6) within the slope is obtained through an inclinometer (3), the inclinometer (3) is installed in an inclinometer hole, and at least one inclinometer (3) is installed in the same inclinometer hole; The physical parameters of the rock / soil mass include density, elastic modulus, Poisson's ratio, cohesion and internal friction angle; Step 2: Obtain the spatial coordinates and deformation monitoring data of the foundation monitoring points with deformation in the same time period. The foundation monitoring points with deformation are called deformed foundation monitoring points, which can be specifically divided into deformed slope monitoring points and deformed slope internal monitoring points; The potential sliding surface is fitted according to the distribution of deformation foundation monitoring points and the accumulated deformation (5); Step 3: Establish a three-dimensional finite element model of the slope and determine the inverse cohesion and inverse internal friction angle of the potential sliding surface (5) by inversion; Step 4: Use the strength reduction method to reduce the inverse cohesion and inverse 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 point and the potential unstable slope; Step 6: The slope, potential unstable slope and its sliding direction are displayed through the visualization platform, and the volume of the potential unstable slope and the safety factor of the slope are displayed.

2. A slope instability assessment method based on deformation monitoring data according to claim 1, characterized in that: In step 2, the potential sliding surface (5) is fitted according to the distribution and cumulative deformation of the deformed foundation monitoring points, as follows: Step 2.1: Obtain all monitoring sections (4) with deformation foundation monitoring points, which are called deformation monitoring sections; Step 2.2: Obtain all foundation monitoring points in the deformation monitoring section, and determine a plurality of constraint line segments (7) based on the deformed foundation monitoring points and the remaining foundation monitoring points; Step 2.3: Fit an ellipsoid with the minimum objective function in space as the potential sliding surface (5); The objective function is equal to the sum of the constraint penalty function and the horizontal settlement ratio function.

3. A slope instability assessment method based on deformation monitoring data according to claim 2, characterized in that: In step 2.2, the plurality of constraint line segments (7) are specifically: in the same monitoring section, taking the highest deformation slope monitoring point as the endpoint, and finding a nearest non-deformation slope monitoring point in the opposite direction of the slope as the other endpoint to form a constraint line segment (7), which is called the upper constraint line segment; In the same monitoring section, the monitoring point on the deformed slope with the lowest elevation is taken as the endpoint, and a nearest non-deformed slope monitoring point is found 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; in the same inclinometer hole (3) of the same monitoring section, the monitoring point inside the deformed slope is connected with the nearest monitoring point inside the non-deformed slope 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 intersection segments of all constraint line segments (7) multiplied by the coefficient α; The length of the constrained line segment extension intersection segment is specifically: if the constrained line segment (7) has an intersection point with the ellipsoid surface, the length of the constrained line segment extension intersection segment is zero; if the constrained line segment (7) does not have an intersection point with the ellipsoid surface, the length of the constrained line segment extension intersection segment is determined by judging the extension; The determination of the extension and determination of the length of the extended intersection segment of the constraint line segment is as follows: starting from the two end points of the constraint line segment (7), extending outward to obtain the intersection point with the ellipsoid; determining a true intersection point according to the difference of the constraint line segment (7); if the true intersection point exists, the distance between the true intersection point and the midpoint of the constraint line segment minus half of the length of the constraint line segment divided by one meter is used as the length of the extended intersection segment of the constraint line segment; wherein, 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 the true intersection point does not exist, the length of the extended intersection segment of the constraint line segment is taken as β.

4. A slope instability assessment method based on deformation monitoring data according to claim 2, characterized in that: In step 2.3, the horizontal settlement ratio function is as follows: Step 2.3.1: Obtain the horizontal displacement monitoring surface component and the monitoring vertical displacement vector of the monitoring point on the deformed slope inside the ellipsoid, and solve the ratio of the horizontal displacement monitoring surface component to the monitoring vertical displacement vector, which is recorded as the monitoring horizontal settlement ratio; The horizontal displacement monitoring surface component refers to the component of the monitoring horizontal displacement vector of the deformation slope monitoring point within the monitoring section; Step 2.3.2: Calculate the similar ellipsoid tangent vector (9) of each deformed slope monitoring point located inside the ellipsoid in the monitoring section (4), and calculate the ratio of the horizontal component to the vertical component of the similar ellipsoid tangent vector (9), which is recorded as the calculated horizontal settlement ratio; The specific solution process of the similar ellipsoid tangent vector (9) is as follows: Step 2.3.2a: Construct a similar ellipsoidal surface (8) in space that is similar to the potential sliding surface (5). The similar ellipsoidal surface meets two requirements: (1) the monitoring point of the deformed slope is located on the similar ellipsoidal surface (8); (2) the similar ellipsoidal surface (8) is obtained by enlarging or reducing the potential sliding surface (5) at a certain ratio while keeping the ellipsoidal center unchanged; Step 2.3.2b: The monitoring section (4) is intersected with the similar ellipsoid (8) to obtain a two-dimensional closed curve, and a tangent vector of the deformed slope monitoring point in the two-dimensional closed curve is solved 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 direction 1; Step 2.3.3: Calculate the sum of the squares of the differences between the monitored horizontal settlement ratio and the calculated horizontal settlement ratio at all deformation slope monitoring points as the horizontal settlement ratio function.

5. The slope instability assessment method based on deformation monitoring data according to claim 1 is characterized in that: In step 3, the inversion determines the inversion cohesion and the inversion internal friction angle of the potential sliding surface (5), as follows: Step 3.1: The physical parameters of the potential sliding surface (5) are taken to be the same as those of the potential unstable slope, and equilibrium is achieved under self-weight stress; The potential unstable slope body is a body obtained by cutting the slope by the potential sliding surface (5); Step 3.2: Extract the calculated deformation of each foundation monitoring point in step 3.1 and record it as the initial calculated deformation; The initial calculated deformation data specifically include: 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 slope monitoring point (6); Step 3.3: Obtain the cohesion c0 and internal friction angle ψ0 of the potential unstable slope; take positive integers m and n, preset m-1 cohesions 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 cohesions and internal friction angles to form (m-1)×(n-1) combinations of preset cohesions and internal friction angles; Step 3.4: Substituting different preset combinations of cohesion and internal friction angles for the potential sliding surface (5), and continuing the calculation based on the results of step 3.1, extracting the calculated deformation of each foundation monitoring point in the calculation results, and recording it as the sliding calculated deformation; The sliding calculation deformation data specifically include: sliding calculation horizontal displacement vector and sliding calculation vertical displacement vector of the slope surface monitoring point (2); sliding calculation horizontal displacement vector of the slope internal monitoring point (6); Step 3.5: Compare the difference between all sliding calculated deformations and the initial calculated deformations with the deformation monitoring data of the foundation monitoring points, and select a set of preset cohesion and internal friction angles with the smallest deviation as the inverse cohesion and inverse internal friction angle of the potential sliding surface (5).

6. A slope instability assessment method based on deformation monitoring data according to claim 5, characterized in that: In steps 3.2 and 3.4, the calculated 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.

7. The slope instability assessment method based on deformation monitoring data according to claim 5 is 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 monitoring point deviation function; the slope monitoring point deviation function is equal to the sum of the sum of the horizontal displacement vector deviations and the vertical displacement vector deviations of all slope monitoring points; the slope monitoring point deviation function is equal to the sum of the horizontal displacement vector deviations of all slope monitoring points; The size of the X component of the monitored horizontal displacement vector is Xmon, the size of the Y component of the monitored horizontal displacement vector is Ymon, the size of the monitored vertical displacement vector is Zmon, the size of the X component of the initially calculated horizontal displacement vector is Xcal1, the size of the Y component of the initially calculated horizontal displacement vector is Ycal1, the size of the initially calculated vertical displacement vector is Zcal1, the size of the X component of the sliding calculated horizontal displacement vector is Xcal2, the size of the Y component of the sliding calculated horizontal displacement vector is Ycal2, the size of the sliding calculated vertical displacement vector is Zcal2, and the sum of the horizontal displacement vector deviation and the vertical displacement vector deviation of the slope monitoring point is equal to (Xmon-(Xcal2-Xcal1)) 2 +(Ymon-(Ycal2-Ycal1)) 2 +(Zmon-(Zcal2-Zcal1)) 2 ; The horizontal displacement vector deviation of the monitoring point in the slope is equal to (Xmon-(Xcal2-Xcal1)) 2 +(Ymon-(Ycal2-Ycal1)) 2 .

8. The slope instability assessment method based on deformation monitoring data according to claim 1 is characterized in that: In step 5, the slope sliding direction is determined according to the horizontal displacement direction of the foundation monitoring point and the potential unstable slope, as follows: Step 5.1: Use multiple sets of cutting planes with a spacing of a in the X, Y and Z directions to segment the potential unstable slope to form multiple segmented bodies (10); Step 5.2: Determine the horizontal displacement direction of each foundation monitoring point as the direction of the monitoring horizontal displacement vector; Step 5.3: Calculate the horizontal displacement direction of each segment (10), specifically: take the spatial position and horizontal movement direction of the foundation monitoring point as basic data, and use inverse distance interpolation to determine the horizontal displacement direction of each segment (10); The horizontal displacement direction of each segment (10) is a vector with a modulus of 1; Step 5.4: Calculate the volume of all segmented bodies (10), and multiply the volume of the segmented body (10) by its horizontal displacement direction, and then calculate the sum of all vectors. The sum of the vectors is the horizontal sliding direction of the potential unstable slope.

9. The slope instability assessment method based on deformation monitoring data according to claim 1 is characterized in that: In step 4, the strength reduction method is used to calculate the safety factor of the slope, specifically: The inverse cohesion and inverse 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, the safety factor of the slope is obtained by dividing 1 by the reduction factor.

10. A computer program product, characterized in that It includes a computer program / instruction, which, when executed by a processor, implements a slope instability assessment method based on deformation monitoring data as described in any one of claims 1 to 9.

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