Slope rock mass structural surface sliding monitoring method

Abstract

The invention relates to the field of slope rock mass monitoring, and aims to provide a slope rock mass structural surface sliding monitoring method which comprises the following steps: S1, measuring and counting occurrence parameters of a slope rock mass structural surface; s2, drawing a hemaphographic projection drawing, and determining a dominant structural plane for controlling the stability of the slope; s3, arranging a plurality of three-way joint measuring meter groups at intervals along the exposure line of the dominant structural plane; s4, counting spatial orientation parameters of each joint meter in the three-way joint meter group, and acquiring displacement data measured by the three-way joint meter group; and S5, according to the statistical spatial orientation parameters and the obtained displacement data, calculating a resultant displacement vector of each three-way joint meter group, and according to the resultant displacement vector, calculating a resultant displacement direction and a displacement value, thereby carrying out safety evaluation analysis on the dominant structural plane. According to the invention, the resultant displacement, the displacement direction and the displacement rate of the dominant structural plane can be monitored to judge the safety risk of the dominant structural plane and evaluate the safety level of the dominant structural plane.

Description

Technical Field

[0001] The invention relates to the field of slope rock mass monitoring, and in particular to a method for monitoring the sliding of a slope rock mass structural surface. Background Art

[0002] A rock slope is a rock mass with a certain slope and free-facing surface that has been artificially modified under the action of natural gravity or to meet engineering needs. The biggest difference between a rock slope and an earth slope is that its stability is controlled by internal structural surfaces, and it has a strong structural nature. Rock slopes contain weak structural surfaces with low strength. Under the influence of external factors such as excavation unloading, rainfall, and earthquakes, the slope tends to slide along these weak structural surfaces, and in severe cases, it can cause the slope to become unstable and fail. These planar structures destroy the integrity of the rock mass, cutting it into relatively independent blocks, forming "weak surfaces" or "separation surfaces" of the rock mass, significantly reducing its shear strength, controlling its deformation characteristics and failure mode, and are the core factors controlling slope stability.

[0003] Different structural surface combinations are often accompanied by different structural surface deformation patterns when they are damaged. Therefore, monitoring slope displacement is the key to ensuring slope stability. There are currently two main methods for slope deformation monitoring. The first is to arrange horizontal and vertical displacement points on the top of the slope and monitor the deformation of the top of the slope through methods such as total stations and leveling. The second is to monitor the internal deformation of the slope through deep horizontal displacement. The above two slope deformation monitoring methods mainly monitor deformation in two directions perpendicular and parallel to the slope direction from the perspective of the entire slope. The monitoring results cannot be used to evaluate the deformation of the structural surface that controls slope stability.

[0004] However, the existing technical means to control the sliding direction of the structural surface is to conduct on-site investigation of the structural surfaces in the slope rock mass, collect statistical information on the occurrence of each structural surface, draw a stereographic projection map, and determine the final sliding direction of the structural surface based on the spatial position relationship of the structural surface. However, due to the complex offset of the various structural surfaces of the slope body, and the influence of the hydrogeological environment, the stress state of the structural surface, especially the compression-torsion fault, the slip direction is often inconsistent with the dip direction. In summary, there is currently a lack of effective technology on the market to monitor the sliding direction and displacement of the slope rock mass control structural surface. Summary of the Invention

[0005] The purpose of the present invention is to provide a slope rock mass structural surface sliding monitoring method, which can monitor the total displacement, displacement direction and displacement rate of the dominant structural surface to determine the safety risk of the dominant structural surface and evaluate its safety level.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A method for monitoring sliding of a rock mass structure surface on a slope comprises the following steps:

[0008] Step S1: measuring and counting the occurrence parameters of the slope rock mass structural surface;

[0009] Step S2: drawing a stereographic projection map based on the statistical occurrence parameters, and determining the dominant structural surface controlling the slope stability by analyzing the stereographic projection map;

[0010] Step S3: Arranging a plurality of three-dimensional joint meter groups at intervals along the exposed line of the dominant structural surface, wherein the three-dimensional joint meter groups include a strike joint meter, a dip joint meter, a normal joint meter, and a data acquisition module; wherein the strike joint meter, the dip joint meter, and the normal joint meter are used to monitor the displacement of the dominant structural surface in the strike, dip, and normal directions, respectively;

[0011] Step S4: Counting the spatial orientation parameters of each joint meter in the three-dimensional joint meter group, and obtaining the displacement data measured by the three-dimensional joint meter group through the data acquisition module;

[0012] Step S5: Calculate the combined displacement vectors of each three-way joint meter group based on the statistical spatial orientation parameters and the obtained displacement data, and calculate the combined displacement direction and displacement value based on the combined displacement vector, so as to perform safety evaluation analysis on the dominant structural surface.

[0013] Compared with the existing technology, the advantages of the present invention are: by performing three-dimensional monitoring on the dominant structural surface, the measured displacement of each three-dimensional measuring point on the dominant structural surface is obtained, and through projection decomposition and synthetic calculation, the displacement value, displacement direction and displacement rate of the combined displacement of each three-dimensional measuring point are obtained, thereby judging the safety risk of the dominant structural surface and evaluating the safety level of the dominant structural surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the vibrating wire joint meter of the present invention;

[0015] Figure 2 This is a schematic diagram of the installation of the trend seam meter of the present invention;

[0016] Figure 3 This is a schematic diagram of the installation of the inclined seam meter of the present invention;

[0017] Figure 4 This is a schematic diagram of the installation of the normal joint meter of the present invention;

[0018] Figure 5 This is an engineering example of a method for monitoring the sliding of a rock mass structure surface on a slope according to the present invention. Figure 1 ;

[0019] Figure 6 This is an engineering example of a method for monitoring the sliding of a rock mass structure surface on a slope according to the present invention. Figure 2 ;

[0020] Figure 7 This is an engineering example of a method for monitoring the sliding of a rock mass structure surface on a slope according to the present invention. Figure 3 ;

[0021] Figure 8 This is an engineering example of a method for monitoring the sliding of a rock mass structure surface on a slope according to the present invention. Figure 4 ;

[0022] Figure 9 This is an engineering example of a method for monitoring the sliding of a rock mass structure surface on a slope according to the present invention. Figure 5 ;

[0023] Figure 10 This is an engineering example of a method for monitoring the sliding of a rock mass structure surface on a slope according to the present invention. Figure 6 .

[0024] Explanation of reference numbers: 100 structural surface exposed line, 2 vibrating wire joint meter, 201 range adjustment rod, 202 transfer rod, 203 universal joint, 204 L-type bracket, 300 cable. DETAILED DESCRIPTION

[0025] The present invention is described in detail below with reference to the accompanying drawings and embodiments:

[0026] A method for monitoring sliding of a rock mass structure surface on a slope comprises the following steps:

[0027] Step S1: measuring and counting the occurrence parameters of the slope rock mass structural surface;

[0028] Step S2: drawing a stereographic projection map based on the statistical occurrence parameters, and determining the dominant structural surface controlling the slope stability by analyzing the stereographic projection map;

[0029] Step S3: Arranging a plurality of three-dimensional joint meter groups at intervals along the exposed line of the dominant structural surface, wherein the three-dimensional joint meter groups include a strike joint meter, a dip joint meter, a normal joint meter, and a data acquisition module; wherein the strike joint meter, the dip joint meter, and the normal joint meter are used to monitor the displacement of the dominant structural surface in the strike, dip, and normal directions, respectively;

[0030] Specifically, the strike joint meter, the inclination joint meter and the normal joint meter can be selected as a vibrating wire joint meter 2, a flux joint meter, etc. In the embodiment of the present invention, the strike joint meter, the inclination joint meter and the normal joint meter are all selected as a vibrating wire joint meter 2, such as Figure 1As shown, the vibrating wire joint meter 2 is an existing technology on the market, which generally includes a transmission rod 202, a range adjustment rod 201 and two universal joints 203; the data acquisition module includes a collector and a cable 300, one end of the cable 300 is connected to the collector, and the other end is electrically connected to each joint meter.

[0031] The installation method of the three-way joint meter group is as follows:

[0032] The two ends of the strike joint meter, the dip joint meter and the normal joint meter are fixed to the rock mass on both sides of the dominant structural surface through the universal joint 203 and the threaded locking parts, such as Figure 2 As shown, the strike joint meter is installed along the exposed line 100 of the structural surface. Since the exposed line 100 of the structural surface is usually an approximate two-dimensional curve, when installing the strike joint meter, an L-shaped bracket 204 is first fixed to the rock mass on one side of the structural surface, and then one end of the joint meter is fixed to the L-shaped bracket 204, and the other end of the strike joint meter is fixed to the rock mass on the other side. Figure 3 As shown, the inclination joint meter is installed along the inclination direction of the structural surface. Figure 4 As shown, the normal joint meter is installed perpendicular to the exposed line 100 of the structural surface.

[0033] Step S4: Counting the spatial orientation parameters of each joint meter in the three-dimensional joint meter group, and obtaining the displacement data measured by the three-dimensional joint meter group through the data acquisition module;

[0034] Step S5: Calculate the combined displacement vectors of each three-way joint meter group based on the statistical spatial orientation parameters and the obtained displacement data, and calculate the combined displacement direction and displacement value based on the combined displacement vector, so as to perform safety evaluation analysis on the dominant structural surface.

[0035] The spatial orientation parameters include the inclination α and the tilt angle β of the joint meter, and the displacement data include the measured displacement s of the joint meter. i The combined displacement vector of the three-axis joint meter group is calculated by the following steps:

[0036] Step S5.1: The measured displacement s measured by each joint meter in the three-way joint meter group is i Decompose into the site coordinate system. Specifically, the site coordinate system stipulates that the positive Y direction is due north (0°), the X direction is due east (90°), and the positive Z direction is vertically upward. The displacement components of each joint meter in the X, Y, and Z directions are calculated. The decomposition calculation formula is as follows:

[0037]

[0038] s iz =s i ·sinα;

[0039] In the above formula:

[0040] s i The displacement is measured by the joint meter, i∈{1,2,3} is the joint meter type, where 1 represents the strike joint meter, 2 represents the dip joint meter, and 3 represents the normal joint meter;

[0041] α is the inclination of the joint gauge;

[0042] β is the inclination angle of the joint meter;

[0043] Step S5.2: Calculate the resultant displacement vector using the displacement components of each joint meter in the X, Y, and Z directions. The calculation formula is as follows:

[0044] (s 1x +s 2x +s 3x , s 1y +s 2y +s 3y , s 1z +s 2z +s 3z )=(s x , s y , s z )

[0045] In the above formula:

[0046] s 1x , s 2x , s 3x They represent the displacement components of the strike joint meter, dip joint meter and normal joint meter in the X direction respectively;

[0047] s 1y , s 2y , s 3y They represent the displacement components of the strike joint meter, dip joint meter and normal joint meter in the Y direction respectively;

[0048] s 1z , s 2z , s 3z They represent the displacement components of the strike joint meter, dip joint meter and normal joint meter in the Z direction respectively;

[0049] s x , s y , s z They represent the components of the total displacement in the X, Y, and Z directions respectively.

[0050] Calculating the combined displacement direction comprises the following steps:

[0051] Step S5.3: Calculate the corresponding resultant displacement direction and displacement amount S based on the calculated resultant displacement vector. The specific calculation formula is as follows:

[0052]

[0053] In the above formula:

[0054] θ is the inclination angle of the resultant displacement;

[0055] The tendency to move together;

[0056] S is the displacement in the direction of the resultant displacement.

[0057] The safety evaluation analysis includes the following steps:

[0058] Step S5.4: Derivative the combined displacement vector of each three-way joint meter group with respect to time to calculate the combined displacement rate, and compare the calculated combined displacement rate with a preset displacement rate threshold to determine whether there is a safety risk on the dominant structural surface.

[0059] Specifically, the preset threshold value of the displacement rate is 2 mm / d. The combined displacement vector of each three-directional joint meter group is differentiated with respect to time (day / d) to calculate the combined displacement rate (mm / d). When the combined displacement rate exceeds the preset threshold value of the displacement rate, it is judged that there is a safety risk on the dominant structural surface.

[0060] The safety evaluation analysis further comprises the following steps:

[0061] Step S5.5: Based on the angle between the combined displacement direction and the slope surface, multiple warning levels are preset and a corresponding risk value is assigned to each warning level. When the combined displacement rate of the three-way joint meter group exceeds the displacement rate threshold, the risk value is determined based on the warning level into which the angle between the combined displacement direction and the slope surface is entered;

[0062] Specifically, the warning level settings are shown in Table 1 below:

[0063]

[0064] Table 1

[0065] In Table 1:

[0066] is the inclination of the combined displacement, and η is the inclination of the slope surface.

[0067] As can be seen from the table above, when the combined displacement rate of the three-way joint meter group exceeds the displacement rate threshold, the warning level can be determined as level one, level two, and level three according to the angle λ between its combined displacement direction and the slope surface, and the assigned values P are obtained respectively. u 5, 3 and 2;

[0068] The risk values of each three-way joint meter group are arithmetic averaged to obtain the safety factor P, and the safety level of the dominant structural surface is evaluated based on the safety factor P. The calculation formula of the safety factor is as follows:

[0069]

[0070] In the above formula:

[0071] P is the safety factor;

[0072] P u Assign the value corresponding to a single three-way joint meter group;

[0073] n is the total number of three-way joint meter groups.

[0074] Furthermore, the safety level evaluation is shown in Table 2 below:

[0075] Security Level Safety factor P A P≥0.5 B 0.2＜P＜0.5 C 0＜P＜0.2 D P＝0

[0076] Table 2

[0077] To further explain the safety level evaluation, the following are specific instructions:

[0078] When the safety factor P of the dominant structural surface is ≥ 0.5, the safety level is A. At this time, the pre-installed sound and light alarm device on site is triggered, and the alarm information is pushed to the relevant management personnel through mobile devices, requiring timely reinforcement measures to ensure the safety of the slope structure;

[0079] When 0.2<P<0.5, the safety level is B, at which point the pre-installed sound and light alarm device on site is triggered, and the alarm information is pushed to relevant management personnel via mobile devices;

[0080] When 0<P<0.2, the security level is C. At this time, the alarm information will be pushed to the relevant management personnel through the mobile device, but the on-site sound and light alarm will not be triggered;

[0081] When P=0, the security level is D and no alarm is triggered.

[0082] After the early warning is triggered, if the total displacement rate of each three-way joint meter group is lower than the displacement rate threshold for 7 consecutive days and the safety level is D, the on-site sound and light alarm and mobile device push alarm will be automatically lifted and the normal monitoring state will be restored.

[0083] To further illustrate the technical effects of the present invention, Figures 1 to 6 , elaborated in detail:

[0084] 1. The structural surface occurrence of an unstable triangle formed by excavation of a rock slope is shown in Table 3 below. It is primarily composed of a small compressional fault on the active sliding surface, a cutting surface of a chlorite schist interlayer, the strike of the roadcut slope, the quarry excavation face (strike 330°), a tensile fracture surface at the rear edge, and a steeply inclined structural surface. The geometric boundaries of this triangle cause its sliding failure direction to be inconsistent with the inclination of the active sliding surface and to be complex and variable. Among them, sliding failure along the direction of the artificial excavation face poses the greatest threat to safe operations. Therefore, clarifying the actual sliding failure direction of the small compressional fault is of great significance.

[0085]

[0086] Table 3

[0087] 2. Plot the statistically calculated attitude parameters onto a stereographic projection to determine the dominant structural surface controlling slope stability. Based on the on-site attitude statistics, when the bottom sliding surface (i.e., the small compressive fault) is combined with the quarry excavation surface, the projection of the small compressive fault is generally located outside the quarry excavation surface, indicating an unstable structure and the dominant structural surface controlling slope stability. Therefore, two sets of three-dimensional joint gauges were installed on the exposed line of the small compressive fault to determine the sliding failure direction and displacement of the dominant structural surface.

[0088] 3. On-site installation of three-dimensional joint gauge on structural surface

[0089] Field investigations revealed that the bottom sliding surface of the triangle was exposed on the south side, creating favorable conditions for monitoring the triangle's sliding. The potential bottom sliding surface of the triangle was clear and unique, laying a solid foundation for the layout of sliding displacement monitoring points within the triangle. However, given that the potential bottom sliding surface of the triangle is a compression-torsional fault plane with large fluctuations in its occurrence and is affected by the sliding resistance of the underlying resistance body, the potential sliding direction of the triangle is still unclear. This potential sliding direction is of great significance for assessing its stability and hazard. Monitoring was performed by installing two sets of three-way joint meters, one at the front and one at the back. The joint meter occurrence information is shown in Table 4.

[0090]

[0091] Table 4

[0092] According to the monitoring data, the displacement components of the first three measuring points X, Y, and Z, as well as the variation curve of the total displacement, are calculated. The results are as follows: Figure 5-6 As shown, the statistical sliding direction results are as follows Figure 7 As shown, the maximum combined displacement of the first three measuring points is 0.23 mm, and the combined displacement direction is 33°∠41°.

[0093] According to the monitoring data, the displacement components of the three measuring points X, Y, and Z, as well as the variation curve of the total displacement, are calculated. The results are as follows: Figure 8-9 As shown, the statistical sliding direction results are as follows Figure 10 As shown, the maximum combined displacement of the three measuring points is 0.58 mm, and the combined displacement direction is 281°∠50°.

[0094] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A method for monitoring sliding of a rock mass structure surface on a slope, characterized in that: The following steps are involved: Step S1: measuring and counting the occurrence parameters of the slope rock mass structural surface; Step S2: drawing a stereographic projection map based on the statistical occurrence parameters, and determining the dominant structural surface controlling the slope stability by analyzing the stereographic projection map; Step S3: Arranging a plurality of three-dimensional joint meter groups at intervals along the exposed line of the dominant structural surface, wherein the three-dimensional joint meter groups include a strike joint meter, a dip joint meter, a normal joint meter, and a data acquisition module; wherein the strike joint meter, the dip joint meter, and the normal joint meter are used to monitor the displacement of the dominant structural surface in the strike, dip, and normal directions, respectively; Step S4: Counting the spatial orientation parameters of each joint meter in the three-dimensional joint meter group, and obtaining the displacement data measured by the three-dimensional joint meter group through the data acquisition module; Step S5: Calculate the combined displacement vectors of each three-way joint meter group based on the statistical spatial orientation parameters and the obtained displacement data, and calculate the combined displacement direction and displacement value based on the combined displacement vector, so as to perform safety evaluation analysis on the dominant structural surface.

2. The method for monitoring the sliding of a rock mass structure surface on a slope according to claim 1, wherein: The spatial orientation parameters include the inclination α and the tilt angle β of the joint meter, and the displacement data include the measured displacement s of the joint meter. i The combined displacement vector of the three-axis joint meter group is calculated by the following steps: Step S5.1: The measured displacement s measured by each joint meter in the three-way joint meter group is i Decompose into the site coordinate system and calculate the displacement components of each joint meter in the X, Y, and Z directions. The decomposition calculation formula is as follows: s iz =s i ·sinα; In the above formula: s i The displacement is measured by the joint meter, i∈{1,2,3} is the joint meter type, where 1 represents the strike joint meter, 2 represents the dip joint meter, and 3 represents the normal joint meter; α is the inclination of the joint gauge; β is the inclination angle of the joint meter; Step S5.2: Calculate the resultant displacement vector using the displacement components of each joint meter in the X, Y, and Z directions. The calculation formula is as follows: (s 1x +s 2x +s 3x ,s 1y +s 2y +s 3y ,s 1z +s 2z +s 3z )=(s x ,s y ,s z ) In the above formula: s 1x , s 2x , s 3x They represent the displacement components of the strike joint meter, dip joint meter and normal joint meter in the X direction respectively; s 1y , s 2y , s 3y They represent the displacement components of the strike joint meter, dip joint meter and normal joint meter in the Y direction respectively; s 1z , s 2z , s 3z They represent the displacement components of the strike joint meter, dip joint meter and normal joint meter in the Z direction respectively; s x , s y , s z They represent the components of the total displacement in the X, Y, and Z directions respectively.

3. The method for monitoring the sliding of a rock mass structure surface on a slope according to claim 2, characterized in that: Calculating the combined displacement direction comprises the following steps: Step S5.3: Calculate the corresponding resultant displacement direction and displacement amount S based on the calculated resultant displacement vector. The specific calculation formula is as follows: In the above formula: θ is the inclination angle of the resultant displacement; The tendency of combined displacement; S is the displacement in the direction of the resultant displacement.

4. The method for monitoring the sliding of a rock mass structure surface on a slope according to claim 3, wherein: The safety evaluation analysis includes the following steps: Step S5.4: Derivative the combined displacement vector of each three-way joint meter group with respect to time to calculate the combined displacement rate, and compare the calculated combined displacement rate with a preset displacement rate threshold to determine whether there is a safety risk on the dominant structural surface.

5. The method for monitoring the sliding of a rock mass structure surface on a slope according to claim 4, characterized in that: The safety evaluation analysis further comprises the following steps: Step S5.5: Based on the angle between the combined displacement direction and the slope surface, multiple warning levels are preset and a corresponding risk value is assigned to each warning level. When the combined displacement rate of the three-way joint meter group exceeds the displacement rate threshold, the risk value is determined based on the warning level into which the angle between the combined displacement direction and the slope surface is entered; The risk values of each three-way joint meter group are arithmetically averaged to obtain the safety factor P, and the safety level of the dominant structural surface is evaluated based on the safety factor P. The calculation formula of the safety factor is as follows: In the above formula: P is the safety factor; P u Assign the value corresponding to a single three-way joint meter group; n is the total number of three-way joint meter groups.

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