Method for evaluating development depth of landslide tension crack, computer readable medium and device

Abstract

The application discloses a landslide tensile crack development depth evaluation method and a computer readable medium and equipment, relates to the field of landslide tensile crack development depth evaluation, and comprises the following steps: arranging a vibration monitoring device in a crack area at the rear edge of a landslide body, and collecting real-time rock-soil body vibration response data; extracting a first-order natural frequency of a vibration signal based on a frequency spectrum analysis method, and determining a modal order; calculating a first-order natural frequency change rate, and calculating a modal order change; and evaluating the tensile crack development depth in combination with the first-order natural frequency change rate and the modal order change. Compared with traditional drilling detection or indirect calculation through crack opening and closing degree, the application can directly invert the crack depth evolution law through the dynamic response characteristics of vibration modal parameters, avoids the secondary damage of a rock-soil structure, solves the limitations of traditional monitoring methods on the evaluation of hidden crack depth, significantly improves the accuracy and timeliness of landslide stability evaluation, and is suitable for the monitoring and early warning of a landslide in a traction type progressive damage mode.

Description

Technical Field

[0001] This invention relates to the field of landslide stability assessment, and more particularly to a method for assessing the depth of landslide tension crack development, as well as a computer-readable medium and device. Background Technology

[0002] Traditional methods for assessing the depth of tension cracks in landslides primarily rely on techniques such as measuring the geometric parameters of surface cracks, borehole exploration, or geophysical exploration. These methods have significant limitations: surface monitoring (e.g., measuring crack width and length) can only indirectly infer shallow crack propagation and is time-sensitive, failing to capture deep damage; borehole exploration (e.g., deploying inclinometers and strain gauges) can obtain local deep data, but invasive operations easily damage the soil and rock structure, are costly, and struggle to achieve large-scale continuous monitoring; geophysical exploration techniques (e.g., ground-penetrating radar and resistivity imaging) are limited by insufficient resolution and environmental interference, exhibiting low sensitivity to millimeter-level cracks and relying on manual, phased exploration, lacking dynamic tracking capabilities. Furthermore, while vibration modal analysis is widely used in engineering structural health monitoring, its applicability in landslide applications remains challenging. For example, the correlation between vibration parameters and landslide stability remains unclear, and further research is needed on how to utilize vibration parameters in landslide stability assessment.

[0003] To address the aforementioned technical challenges, this invention proposes a non-invasive assessment method based on vibration modal analysis theory and soil damage mechanics, combined with high-precision sensors and dynamic signal analysis algorithms. By acquiring real-time vibration response data of landslide bodies, extracting the rate of change of the first-order natural frequency and the characteristics of modal order changes, a method for assessing crack depth based on vibration parameters is constructed. This enables dynamic inversion of the depth of hidden cracks, providing highly timely and accurate quantitative data support for landslide stability early warning and disaster prevention. Summary of the Invention

[0004] The purpose of this invention is to provide a method for assessing the development depth of landslide tension cracks, as well as a computer-readable medium and device, thereby solving the problems of soil and rock structure damage, monitoring lag, and insufficient accuracy in assessing the depth of hidden cracks caused by reliance on borehole detection or surface parameter calculation in traditional methods.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a method for assessing the development depth of landslide tension cracks, comprising the following steps:

[0006] S1. Vibration monitoring equipment is deployed in the crack zone at the rear edge of the landslide body to collect real-time vibration response data of the soil and rock mass.

[0007] S2, The first natural frequency of the vibration signal is extracted based on the spectrum analysis method, and the modal order is determined;

[0008] S3, calculate the rate of change of the first natural frequency, and calculate the change of the modal order;

[0009] S4, combining the rate of change of the first-order natural frequency and the change of the modal order to evaluate the depth of tensile crack development.

[0010] Preferably, S1 specifically comprises:

[0011] Vibration pickups were installed 1-2m away from the toe of the landslide at the location of the maximum tension crack in the landslide body to collect vibration time history curves. The acquisition frequency was 200Hz and the acquisition time was 10min each time.

[0012] Preferably, the vibration pickup is a piezoelectric vibration pickup, a piezoresistive vibration pickup, a capacitive vibration pickup, an electromagnetic vibration pickup, a fiber optic vibration pickup, or a laser Doppler vibration meter.

[0013] Preferably, S2 specifically comprises:

[0014] S21. Divide the 10-minute vibration data into 60 segments, each segment lasting 10 seconds, and calculate the average value of each segment. Average value of 10-minute vibration data Compare the average values ​​of each vibration data segment Compared with the mean of the entire data segment deviation value And calculate the deviation rate. when When the data segment is considered abnormal, the abnormal data is removed, and the remaining data is combined into new data x'.

[0015] S22. Using the synthesized new data x', the spectrum is calculated using the Welch method. The parameters of the Welch method are set to a length of 10s for each small vibration data segment, a number of overlapping samples of 2s, and the window function is the Hanning window function. The power spectrum is calculated, and the spectrum is obtained by squaring the power spectrum. The frequency corresponding to the first peak in the spectrum is selected as the first natural frequency.

[0016] S23. Continue to examine the other peaks in the spectrum, which correspond to other natural frequencies. The number of peaks in the spectrum indicates the number of modal orders.

[0017] Preferably, S3 specifically comprises:

[0018] S31. The first stable first-order natural frequency after equipment installation is taken as the initial first-order natural frequency f0. During monitoring, the first-order natural frequency is calculated as f0 for each data acquisition. t Then the change in the first-order natural frequency is Δf = |f t -f0|, the rate of change of the first-order natural frequency

[0019] S32. The number of peak values ​​that stabilize for the first time after equipment installation is taken as the initial modal order n0, and the modal order during monitoring is n. t If n t -n0≠0 indicates that the modal order n has changed.

[0020] Preferably, S4 specifically comprises:

[0021] The development of tension cracks will eventually break up the landslide body, causing changes in the structure and boundary conditions of the landslide system, which in turn leads to changes in the first natural frequency and modal order. The development depth of tension cracks is assessed based on the rate of change of the first natural frequency and the changes in modal order.

[0022] For soil landslides:

[0023] Then the depth of tension crack development accounts for less than 40%;

[0024] Therefore, 40% ≤ the proportion of tension crack development depth < 60%;

[0025] Then 60% ≤ the proportion of tension crack development depth < 80%;

[0026] If the modal order n changes, the proportion of tension crack propagation depth will be ≥80%;

[0027] For rock landslides:

[0028] Then the depth of tension crack development accounts for less than 40%;

[0029] Therefore, 40% ≤ the proportion of tension crack development depth < 60%;

[0030] Then 60% ≤ the proportion of tension crack development depth < 80%;

[0031] If the modal order n changes, the proportion of tension crack development depth will be ≥80%.

[0032] Preferably, the computer-readable storage medium includes a stored computer program, wherein the computer program, when executed, controls the device containing the computer-readable storage medium to perform the above-described method.

[0033] Preferably, the computer device includes a memory, a processor, and a program stored in the memory and executable thereon, which, when executed by the processor, implements the steps of the method described above.

[0034] The beneficial effects of this invention are as follows: Real-time acquisition of soil and rock response data through non-invasive vibration monitoring, combined with spectral analysis to extract the first-order natural frequency change rate and modal order change characteristics, constructs a dynamic inversion model for crack depth, overcoming the destructive limitations of traditional borehole detection and the lag bottleneck of surface monitoring; innovatively integrating dual-parameter indicators (sensitively capturing damage through the first-order natural frequency change rate and identifying critical states through modal order jumps) to achieve accurate assessment of hidden crack depth; employing segmented screening and Welch spectral optimization algorithms to suppress noise, and differentially adapting to soil / rock landslide assessment thresholds, significantly improves monitoring reliability in complex environments, providing high-efficiency and low-cost technical support for landslide progressive damage early warning. It can be widely applied to assess the crack development degree and stability of slopes in water conservancy and hydropower projects, steep slopes, and highway and railway slopes. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the execution flow of the landslide tension crack development depth assessment method provided in an embodiment of the present invention;

[0036] Figure 2 These are partial vibration acceleration time history curves collected in an embodiment of the present invention;

[0037] Figure 3 This is the initial spectrum diagram of an embodiment of the present invention;

[0038] Figure 4 This is a spectrum diagram from a routine monitoring session according to an embodiment of the present invention;

[0039] Figure 5 This is a graph showing the change in the first-order natural frequency according to an embodiment of the present invention. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0041] Example 1

[0042] This embodiment provides a method for assessing the development depth of tensile cracks in landslides. The execution flow of this method is as follows: Figure 1 As shown, it includes the following steps:

[0043] S1. Vibration monitoring equipment is deployed in the crack zone at the rear edge of the landslide body to collect real-time vibration response data of the soil and rock mass.

[0044] Specifically, in this embodiment, the above-mentioned S1 implementation process is as follows:

[0045] S11. Vibration pickups are installed 1 to 2 meters away from the toe of the slope at the location where the tension crack of the landslide body is at its maximum. The vibration pickups are piezoelectric, piezoresistive, capacitive, electromagnetic, fiber optic, and laser Doppler vibration meters.

[0046] S12, collect vibration time history curves at a frequency of 200Hz, with each collection lasting 10 minutes.

[0047] S2, the first natural frequency of the vibration signal is extracted based on the spectrum analysis method, and the modal order is determined;

[0048] Specifically, in this embodiment, the above-mentioned S2 implementation process is as follows:

[0049] S21, Divide the 10-minute vibration data into 60 segments, each segment lasting 10 seconds, and calculate the average value of each segment. Average value of 10-minute vibration data Compare the average values ​​of each vibration data segment Compared with the mean of the entire data segment deviation value And calculate the deviation rate. when If the data segment is considered outlier, remove the outlier data and combine the remaining data into a new data segment x'.

[0050] S22. Using the synthesized new data x', the spectrum is calculated using the Welch method. The parameters of the Welch method are set to a length of 10s for each small vibration data segment, a number of overlapping samples of 2s, and the Hanning window function is used. The power spectrum is calculated, and the spectrum is obtained by squaring the power spectrum. The frequency corresponding to the first peak in the spectrum is selected as the first natural frequency.

[0051] S23, continue to look at the other peaks in the spectrum, which correspond to other natural frequencies. The number of peaks in the spectrum indicates the number of modal orders.

[0052] S3, calculate the rate of change of the first natural frequency, and calculate the change of the modal order;

[0053] Specifically, in this embodiment, the above-mentioned S3 implementation process is as follows:

[0054] S31, the first stable first-order natural frequency after equipment installation is taken as the initial first-order natural frequency f0. During monitoring, the first-order natural frequency is calculated as f0 for each data acquisition. t Then the change in the first-order natural frequency is Δf = |f t -f0|, the rate of change of the first-order natural frequency

[0055] S32, the number of peak values ​​that stabilize for the first time after equipment installation is taken as the initial modal order n0, and the modal order during monitoring is n. t If n t -n0≠0 indicates that the modal order n has changed.

[0056] S4, combining the first-order natural frequency change rate and modal order change to assess the propagation depth of tension cracks;

[0057] Specifically, in this embodiment, the propagation depth of the tensile crack is evaluated based on the rate of change of the first natural frequency and the change of the modal order:

[0058] For soil landslides:

[0059] Then the depth of tension crack development accounts for less than 40%;

[0060] Therefore, 40% ≤ the proportion of tension crack development depth < 60%;

[0061] Then 60% ≤ the proportion of tension crack development depth < 80%;

[0062] If the modal order n changes, the proportion of tension crack development depth will be ≥80%.

[0063] For rock landslides:

[0064] Then the depth of tension crack development accounts for less than 40%;

[0065] Therefore, 40% ≤ the proportion of tension crack development depth < 60%;

[0066] Then 60% ≤ the proportion of tension crack development depth < 80%;

[0067] If the modal order n changes, the proportion of tension crack development depth will be ≥80%.

[0068] Second Embodiment

[0069] The implementation process and effects of the method of the present invention will be described in detail below with reference to a practical application example of the technical solution of the present invention. Specifically, the implementation process of the method includes the following steps:

[0070] S1. Vibration monitoring equipment is deployed in the crack zone at the rear edge of the landslide body to collect real-time vibration response data of the soil and rock mass.

[0071] Specifically, in this embodiment, the above-mentioned S1 implementation process is as follows:

[0072] S11, a piezoelectric vibration pickup is installed 1.2m away from the toe of the slope, corresponding to the location of the maximum tension crack in the landslide body.

[0073] S12, collect vibration time history curves at a frequency of 200Hz, with each collection lasting 10 minutes. Figure 2 As shown.

[0074] S2, the first natural frequency of the vibration signal is extracted based on the spectrum analysis method, and the modal order is determined;

[0075] Specifically, in this embodiment, the above-mentioned S2 implementation process is as follows:

[0076] S21, Divide the 10-minute vibration data into 60 segments, each segment lasting 10 seconds, and calculate the average value of each segment. Average value of 10-minute vibration data Compare the average values ​​of each vibration data segment Compared with the mean of the entire data segment deviation value And calculate the deviation rate. when If the data segment is considered outlier, remove the outlier data and combine the remaining data into a new data segment x'.

[0077] S22. Using the synthesized new data x', the spectrum is calculated using the Welch method. The parameters of the Welch method are set to a length of 10s for each small vibration data segment, a number of overlapping samples of 2s, and the Hanning window function is used. The power spectrum is calculated, and the spectrum is obtained by squaring the power spectrum. The frequency corresponding to the first peak in the spectrum is selected as the first natural frequency.

[0078] S23, continue to look at the other peaks in the spectrum, which correspond to other natural frequencies. The number of peaks in the spectrum indicates the number of modal orders.

[0079] S3, calculate the rate of change of the first natural frequency, and calculate the change of the modal order;

[0080] Specifically, in this embodiment, the above-mentioned S3 implementation process is as follows:

[0081] S31, the first stable first-order natural frequency after equipment installation is taken as the initial first-order natural frequency f0, such as... Figure 3 As shown, during monitoring, the first-order natural frequency f is calculated for each data acquisition. t ,like Figure 4 As shown, the curve of the first-order natural frequency change over a period of time is as follows: Figure 5 As shown, the first-order natural frequency change value Δf=|f t-f0|, the rate of change of the first-order natural frequency

[0082] S32, the number of peak values ​​that stabilize for the first time after equipment installation is taken as the initial modal order n0, and the modal order during monitoring is n. t If n t -n0≠0 indicates that the modal order n has changed.

[0083] S4, combining the first-order natural frequency change rate and modal order change to assess the propagation depth of tension cracks;

[0084] Specifically, in this embodiment, the landslide is a soil landslide, and the depth of tensile crack development is assessed based on the rate of change of the first natural frequency and the change of the modal order:

[0085] Then the depth of tension crack development accounts for less than 40%;

[0086] Therefore, 40% ≤ the proportion of tension crack development depth < 60%;

[0087] Then 60% ≤ the proportion of tension crack development depth < 80%;

[0088] If the modal order n changes, the proportion of tension crack development depth will be ≥80%.

[0089] according to Figure 5 And the evaluation rules, the rate of change of the first natural frequency is Right now The modal order n did not change, which indicates that the development depth of the tension cracks was between 60% and 80%, and the tension cracks had developed to a certain extent, suggesting that the landslide may be in a weakly stable state.

[0090] By adopting the above-disclosed technical solutions of this invention, secondary damage to landslide structures caused by drilling is avoided, achieving non-destructive monitoring; noise is suppressed by segmented data screening and Welch method spectrum optimization, improving data reliability; the depth of hidden cracks is inverted by multi-parameter fusion (natural frequency and modal order), overcoming the indirect limitations of surface parameter estimation; and it is compatible with soil / rock landslide differential models, adapting to long-term stable monitoring in complex environments, providing a timely and accurate scientific basis for landslide stability early warning and engineering decision-making.

[0091] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented, in whole or in part, as a computer program product, the computer program product includes one or more computer instructions. When the computer program instructions are loaded or executed on a computer, all or part of the processes or functions described in the embodiments of the present invention are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape) or an optical medium.

[0092] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for assessing the development depth of tension cracks in landslides, characterized in that, Includes the following steps: S1. Vibration monitoring equipment is deployed in the crack zone at the rear edge of the landslide body to collect real-time vibration response data of the soil and rock mass; S2. Extract the first-order natural frequency of the vibration signal based on the spectrum analysis method, and determine the modal order, including: S21. Divide the 10-minute vibration data into 60 segments, each segment lasting 10 seconds, and calculate the average value of each segment. The average value of 10-minute vibration data Compare the average values ​​of each vibration data segment. Compared with the mean of the entire data segment deviation value And calculate the deviation rate. ,when If the data segment is considered abnormal, the abnormal data is removed, and the remaining data is combined into new data. ; S22. Using synthesized new data The spectrum was calculated using the Welch method. The parameters of the Welch method were set to a length of 10s for each vibration data segment, a number of overlapping samples of 2s, and a Hanning window function. The power spectrum was calculated, and the spectrum was obtained by squaring the power spectrum. The frequency corresponding to the first peak in the spectrum was selected as the first natural frequency. S23. Continue to examine the other peaks in the spectrum, which correspond to other natural frequencies. The number of peaks in the spectrum indicates the number of modal orders. S3. Calculate the rate of change of the first natural frequency and the change of the modal order; S4. Evaluate the depth of tensile crack development by combining the rate of change of the first natural frequency and the modal order.

2. The method for assessing the development depth of landslide tension cracks according to claim 1, characterized in that, S1 refers to: installing a vibration pickup at a distance of 1-2m from the toe of the slope corresponding to the location of the maximum tension crack in the landslide body to collect vibration time history curves at a frequency of 200Hz and a duration of 10min for each acquisition.

3. The method for assessing the development depth of landslide tension cracks according to claim 2, characterized in that, The vibration pickup can be a piezoelectric vibration pickup, a piezoresistive vibration pickup, a capacitive vibration pickup, an electromagnetic vibration pickup, a fiber optic vibration pickup, or a laser Doppler vibration meter.

4. The method for assessing the development depth of landslide tension cracks according to claim 1, characterized in that, S3 includes: S31. The first stable first-order natural frequency after equipment installation is taken as the initial first-order natural frequency. During monitoring, the first-order natural frequency is calculated for each data acquisition. The change value of the first natural frequency rate of change of first natural frequency ; S32. The number of peak values ​​that stabilize for the first time after equipment installation is taken as the initial modal order. The modal order during monitoring is ,like This indicates the modal order. Things have changed.

5. The method for assessing the development depth of landslide tension cracks according to claim 1, characterized in that, The S4 includes: the development of tension cracks will eventually divide the landslide body, causing changes in the structure and boundary conditions of the landslide system, thereby causing changes in the first natural frequency and modal order, and the development depth of tension cracks is evaluated based on the rate of change of the first natural frequency and the changes in modal order. For soil landslides: The proportion of the development depth of tension cracks ; ,but Percentage of tensile crack development depth ; ,but Percentage of tensile crack development depth ; or modal order If changes occur, the proportion of the tensile crack development depth will change. ; For rock landslides: The proportion of the development depth of tension cracks ; ,but Percentage of tensile crack development depth ; ,but Percentage of tensile crack development depth ; or modal order If changes occur, the proportion of the tensile crack development depth will change. .

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored computer program, wherein, when the computer program is executed, it controls the device on which the computer-readable storage medium is located to perform the method as described in any one of claims 1-5.

7. A computer device, characterized in that, The computer device includes a memory, a processor, and a program stored in and executable on the memory, the program being executed by the processor to implement the steps of the method as described in any one of claims 1-5.

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