Rainfall type landslide early warning method based on multi-field coupling

Abstract

The invention provides a rainfall type landslide early warning method based on multi-field coupling, and relates to the technical field of landslide early warning, and the method comprises the steps: dividing a slope into a plurality of sub-regions, carrying out the stress analysis of each sub-region, analyzing the stress condition of each sub-region under the action of the own gravity and an internal friction angle, and analyzing the pressure influence degree of the upper side sub-region, thereby achieving the early warning of the rainfall type landslide. The method comprises the following steps of: generating the anti-sliding capacity of a corresponding sub-region, analyzing the gravity component and the influence degree of upper side pressure of each sub-region, generating the sliding displacement capacity of the corresponding sub-region, and outputting a slope early warning coefficient in real time by analyzing the force field and combining the water content change caused by rainfall. And the risk of generating landslide displacement in the corresponding sub-region is warned.

Description

Technical Field

[0001] The present invention relates to the technical field of landslide early warning, and specifically to a rainfall-induced landslide early warning method based on multi-field coupling. Background Technique

[0002] Slope landslides are a common form of geological disasters, and their occurrence is often affected by multiple factors, among which rainfall is one of the most important inducing factors. Rainfall can affect the stability of slopes through various channels. First of all, precipitation will increase the water content of the soil, resulting in an increase in soil pore water pressure. When the pore water pressure exceeds the effective stress between soil particles, the shear strength of the soil mass will be significantly reduced, thus increasing the risk of landslide occurrence. Secondly, the erosion effect of the water flow and soil caused by rainfall will change the shape and structure of the slope surface, weakening the stability of the slope. In addition, continuous or heavy rainfall may also cause the groundwater level to rise, forming a water gushing phenomenon, which will exacerbate the liquefaction and fluidity of the soil mass, further promoting the occurrence of landslides. Especially in the case of scarce or damaged vegetation on slopes, the infiltration and transportation of water will become more significant, thus accelerating the occurrence of landslides.

[0003] Generally, due to the different soil property parameters and inclination angles of the slopes themselves, the degrees of influence by rainfall are also different. For the same rainfall, the probabilities of landslides occurring on different slopes are also different. Therefore, for slopes with specific inclination angles and specific soil properties, it is difficult for humans to accurately judge the magnitude of their sliding risks.

[0004] The above information disclosed in the background art section is only used to enhance the understanding of the background of the present disclosure, so it may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a rainfall-induced landslide early warning method based on multi-field coupling to solve the problems raised in the above background art.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] A rainfall-induced landslide early warning method based on multi-field coupling, based on the coupled analysis of the force field and rainfall, the specific steps include:

[0008] S1. Divide the slope into N sub-regions equally from top to bottom, number the sub-regions, and collect the soil parameters of the sub-regions. The soil parameters include volumetric water content, saturated volumetric water content of the soil, volume, soil cohesion, water influence coefficient, and soil specific weight.

[0009] S2. Conduct a correlation analysis on soil parameters to generate soil weight and effective cohesion. The soil weight is the gravity of the sub-region, and the effective cohesion is the cohesion of the sub-region obtained by comprehensively considering water acquisition.

[0010] S3. Collect the initial water content and initial internal friction angle of each sub-region. Conduct a correlation analysis on the initial internal friction angle, initial water content, and volumetric water content to generate a real-time internal friction angle, which is used to reflect the estimated value of the real-time internal friction angle of the slope during rainfall. Conduct a correlation analysis on the real-time internal friction angle to generate a pressure coefficient, which is used to reflect the degree of pressure influence of the i-1 sub-region on the current sub-region.

[0011] S4. Conduct a correlation analysis on soil weight, volume, and effective cohesion to generate the anti-sliding force of the slope. Conduct a correlation analysis on soil weight and slope inclination to generate the sliding force of the slope. The anti-sliding force of the slope is used to reflect the anti-sliding ability of the slope, and the sliding force of the slope is used to reflect the sliding force of the slope.

[0012] S5. Conduct a correlation analysis on the anti-sliding force of the slope and the pressure coefficient to generate a comprehensive anti-sliding index of the slope, which is used to reflect the anti-sliding degree of the current sub-region obtained by comprehensively considering the forces of other sub-regions. Conduct a correlation analysis on the sliding force of the slope and the pressure coefficient to generate a comprehensive sliding index of the slope, which is used to reflect the sliding force situation of the current sub-region obtained by comprehensively considering the forces of other sub-regions.

[0013] S6. Conduct a correlation analysis on the comprehensive anti-sliding index XZK i and the comprehensive sliding index XZX i to generate a slope warning coefficient Δ. Compare the slope warning coefficient Δ with the threshold ε and output the warning level.

[0014] Furthermore, the subscript i is used to index the sub-region. The volumetric water content θ i of the soil in the i-th sub-region is monitored in real time through a soil moisture sensor. The saturated volumetric water content of the soil in the i-th sub-region is measured by the soaking method. Conduct a correlation analysis on the volumetric water content θ i and the saturated volumetric water content of the soil to generate the soil saturation S i . The formula is as follows:

[0015]

[0016] The soil saturation S i is the volumetric water content of the soil in the i-th sub-region.

[0017] Furthermore, the volume V iis the volume of the i-th sub-region, for the soil saturation S i , the volume V i perform a correlation analysis to generate the soil weight W of the i-th sub-region i , and the formula is:

[0018]

[0019] where is the unit weight of dry soil in the i-th sub-region, measured through experiments is the unit weight of water the soil weight W of the i-th sub-region i is used to reflect the gravity of the slope sub-region considering moisture

[0020] soil cohesion c i is the initial cohesion of the soil in the i-th sub-region, measured through experiments. The moisture influence coefficient k is a coefficient used to reflect the influence of soil moisture on cohesion, measured through soil shear experiments. For the soil cohesion c i , the moisture influence coefficient k, the soil saturation S i perform a correlation analysis to generate the effective cohesion and the formula is:

[0021]

[0022] The effective cohesion is the cohesion of the soil in the i-th sub-region considering the influence of soil moisture

[0023] Furthermore, the initial internal friction angle the initial water content are the internal friction angle and water content of the i-th sub-region before rainfall. For the initial internal friction angle the initial water content and the volumetric water content θ i perform a correlation analysis to generate the real-time internal friction angle and the formula is:

[0024]

[0025] b is the sensitivity coefficient of the internal friction angle to the change in water content. The real-time internal friction angle is used to reflect the estimated value of the real-time internal friction angle of the slope during rainfall

[0026] Perform a correlation analysis on the real-time internal friction angle to generate the pressure coefficient μ i , and the formula is:

[0027]

[0028] Among them, β i is the inclination angle of the i-th sub-region, and β i-1 is the inclination angle of the i-1 sub-region. The pressure coefficient is used to reflect the degree of pressure influence of the i-1 sub-region on the i-th sub-region.

[0029] Furthermore, a correlation analysis is performed on the soil weight W i , volume V i and effective cohesive force to generate the slope anti-sliding force XK i , and the formula based on is:

[0030]

[0031] A correlation analysis is performed on the soil weight W i , slope inclination angle β i to generate the slope sliding force XX i , and the formula based on is:

[0032] XX i = W i * sinβ i

[0033] Among them, the slope anti-sliding force XK i is used to reflect the anti-sliding ability of the i-th sub-region affected by itself, and the slope sliding force XX i is used to reflect the sliding ability of the i-th sub-region affected by itself.

[0034] Furthermore, a correlation analysis is performed on the slope anti-sliding force XK i , pressure coefficient μ i to generate the slope comprehensive anti-sliding index XZK i , and the formula based on is:

[0035]

[0036] A correlation analysis is performed on the slope sliding force and pressure coefficient to generate the slope comprehensive sliding index XZX i , and the formula based on is:

[0037]

[0038] The slope comprehensive anti-sliding index XZK i is used to reflect the comprehensive value of the anti-sliding ability of the i-th sub-region itself and the anti-sliding ability caused by the action of other upper sub-regions, and the slope comprehensive sliding index XZX i is used to reflect the comprehensive value of the sliding ability of the i-th sub-region itself and the sliding ability caused by the action of other upper sub-regions.

[0039] Further, perform a correlation analysis on the comprehensive anti-sliding index XZK of the slope i and the comprehensive sliding index XZX of the slope i to generate a slope warning coefficient Δ i , and the formula based on is:

[0040]

[0041] The slope warning coefficient Δ i is used to reflect the ratio of the sliding ability to the anti-sliding ability of the i-th sub-region, and the threshold ε is set to 1. When Δ i ≥ε, trigger the first-level rainfall warning alarm. At this time, the probability of landslide in the corresponding sub-region is extremely high, and corresponding measures need to be taken; when ε / 2 < Δ i <ε, trigger the second-level rainfall warning alarm. At this time, there is a certain probability of landslide in the corresponding sub-region, and it needs to be monitored and fed back in a timely manner. When Δ i ≤ε / 2, do not trigger the rainfall warning alarm.

[0042] Compared with the prior art, the beneficial effects of the present invention are:

[0043] By dividing the slope into multiple sub-regions, the present invention analyzes the force on each sub-region, analyzes its force condition under its own gravity and internal friction angle, and analyzes the influence degree of the pressure from the upper sub-region, so as to generate the anti-slip ability of the corresponding sub-region. In addition, it also analyzes the gravity component of each sub-region itself and the influence degree of the upper-side pressure, and generates the slip displacement ability of the corresponding sub-region. Through the analysis of the force field, at the same time, combined with the change in water content caused by rainfall, the slope warning coefficient is output in real time to warn of the risk of landslide displacement in the corresponding sub-region. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic flow chart of the overall method of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0045] In order to make the purpose, technical solutions and advantages of the present invention clearer, the following further describes the present invention in detail with reference to specific embodiments.

[0046] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the field to which the present invention pertains. The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. Words such as "comprising" or "including" mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Upper", "lower", "left", "right", etc. are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0047] Embodiment:

[0048] Please refer to Figure 1 , the present invention provides a technical solution:

[0049] A rainfall-induced landslide warning method based on multi-field coupling, based on the coupled analysis of the force field and rainfall. By dividing the slope into N sub-regions and analyzing each sub-region, the self-sliding ability, anti-sliding ability of each sub-region, as well as the sliding ability and anti-sliding ability acting on this sub-region under the action of other upper sub-regions are obtained. Combining the changes in water content and soil cohesion caused by rainfall, comprehensive analysis is carried out to obtain the slope warning coefficient, so as to provide an assessment for the warning of slope landslides during rainfall. The specific steps include:

[0050] Step 1: Divide the slope into N equal sub-regions from top to bottom, number the sub-regions, and the numbering is carried out in sequence according to the principle from top to bottom. Collect the soil parameters of the sub-regions, and the soil parameters include volumetric water content, soil saturated volumetric water content, volume, soil cohesion, water influence coefficient, soil unit weight;

[0051] The subscript i is used to index the sub-regions. During rainfall, the volumetric water content θ of the soil in the i-th sub-region is monitored by a soil moisture sensor i , the volumetric water content θ i is the water content per unit volume in the soil in real time during rainfall. When there is no rainfall, take soil samples from the sub-regions and measure the soil saturated volumetric water content of the i-th sub-region by the soaking method Perform a correlation analysis on the volumetric water content θ i and the soil saturated volumetric water content to generate the soil saturation S i , and the formula is:

[0052]

[0053] Soil saturation S i is the volumetric water content of the soil in the i-th sub-region.

[0054] Step 2: Conduct a correlation analysis on soil parameters to generate soil weight and effective cohesion. The soil weight is the gravity of the sub-region, and the effective cohesion is the cohesion of the sub-region considering water acquisition.

[0055] Volume V i is the volume of the i-th sub-region, obtained by measurement. Conduct a correlation analysis on the soil saturation S i and volume V i to generate the soil weight W of the i-th sub-region i , and the formula is:

[0056]

[0057] where is the unit weight of dry soil in the i-th sub-region, measured by the drying method experiment, is the unit weight of water, The soil weight W of the i-th sub-region i is used to reflect the gravity of the slope sub-region considering moisture, that is, the gravity of the slope sub-region considering the influence of rainfall. By analyzing the gravity of the sub-region, its sliding ability and anti-sliding ability can be further obtained;

[0058] Soil cohesion c i is the initial cohesion of the soil in the i-th sub-region, that is, the cohesion without moisture, measured by the direct shear test. The moisture influence coefficient k is used to reflect the coefficient of the influence of soil moisture on cohesion, measured by the soil shear test. The specific steps include: preparing soil samples, measuring the initial moisture content, conducting a direct shear test and gradually increasing the moisture content, obtaining the cohesion corresponding to the moisture content, and fitting the output moisture influence coefficient k by the least squares method. Conduct a correlation analysis on the soil cohesion c i , moisture influence coefficient k, and soil saturation S i to generate the effective cohesion and the formula is:

[0059]

[0060] Effective cohesion is the cohesion of the soil in the i-th sub-region considering the influence of soil moisture.

[0061] Step 3: Collect the initial water content and initial internal friction angle of each sub-region, conduct a correlation analysis on the initial internal friction angle, initial water content, and volumetric water content to generate a real-time internal friction angle, which is used to reflect the estimated value of the real-time internal friction angle of the slope during rainfall. Conduct a correlation analysis on the real-time internal friction angle to generate a pressure coefficient, which is used to reflect the degree of pressure influence of the i-1 sub-region on the sub-region;

[0062] The internal friction angle is an important parameter in soil mechanics, representing the relationship between the frictional force between soil particles and the normal pressure. The internal friction angle refers to the ratio of the shear strength caused by the friction between particles to the effective normal stress when the soil undergoes shear failure. The initial internal friction angle Initial water content is the internal friction angle and water content of the i-th sub-region before rainfall. For the initial internal friction angle Initial water content and the volumetric water content θ i conduct a correlation analysis to generate a real-time internal friction angle The formula is as follows:

[0063]

[0064] b is the sensitivity coefficient of the internal friction angle to the change in water content. The real-time internal friction angle is used to reflect the estimated value of the real-time internal friction angle of the slope during rainfall; the internal friction angle changes with the water content. As the water content increases, the internal friction angle of the soil decreases. Water reduces the frictional force between particles. The sensitivity coefficient b of the internal friction angle to the change in water content is obtained through direct shear tests and triaxial tests.

[0065] Conduct a correlation analysis on the real-time internal friction angle to generate a pressure coefficient μ i , and the formula is as follows:

[0066]

[0067] where β i is the inclination angle of the i-th sub-region, β i-1 is the inclination angle of the i-1 sub-region. The angle difference affects the interaction between adjacent layers, especially under the action of gravity and friction. cos(β i-i -β i ) is used to describe the degree of inclination angle deviation between two adjacent layers, shows the additional influence caused by the internal friction angle and the interlayer angle difference. This value ignores the weight effect and only analyzes the angles of the inclination angle and the internal friction angle. The pressure coefficient μ i reflects the degree of influence of the remaining sliding force of the i-1 sub-region on the i-th sub-region.

[0068] Step 4: Conduct a correlation analysis on the soil weight, volume, and effective cohesion to generate the slope anti-sliding force, and conduct a correlation analysis on the soil weight and slope inclination angle to generate the slope sliding force. The slope anti-sliding force is used to reflect the anti-sliding ability of the slope, and the slope sliding force is used to reflect the sliding force of the slope;

[0069] For the soil weight W i 、volume V i and effective cohesion conduct a correlation analysis to generate the slope anti-sliding force XK i , and the formula is:

[0070]

[0071] is used to reflect the additional resistance generated by the effective cohesion of the soil, is used to reflect the anti-sliding force generated by synthesizing the comprehensive gravity, internal friction angle, and inclination angle. After comprehensive analysis, the slope anti-sliding force XK i is generated;

[0072] For the soil weight W i 、slope inclination angle β i conduct a correlation analysis to generate the slope sliding force XX i , and the formula is:

[0073] XX i =W i *sinβ i

[0074] Among them, the slope anti-sliding force XK i is used to reflect the anti-sliding ability of the i-th sub-region affected by itself, and the slope sliding force XX i is used to reflect the sliding ability of the i-th sub-region affected by its own weight and inclination angle.

[0075] Step 5: Conduct a correlation analysis on the slope anti-sliding force and the pressure coefficient to generate the slope comprehensive anti-sliding index. The slope comprehensive anti-sliding index is used to reflect the anti-sliding degree of the current sub-region obtained by synthesizing the forces of other sub-regions. Conduct a correlation analysis on the slope sliding force and the pressure coefficient to generate the slope comprehensive sliding index. The slope comprehensive sliding index is used to reflect the sliding force situation of the current sub-region obtained by synthesizing the forces of other sub-regions;

[0076] For the slope anti-sliding force XK i 、pressure coefficient μ i conduct a correlation analysis to generate the slope comprehensive anti-sliding index XZK i , and the formula is:

[0077]

[0078] Analyze the forces on the numbered sub - regions in turn according to the multiplication rule, and then combine with its own anti - sliding ability to generate the slope comprehensive anti - sliding index XZK after synthesis. i ;

[0079] Conduct a correlation analysis on the slope sliding force and the pressure coefficient to generate the slope comprehensive sliding index XZX. i , and the formula is:

[0080]

[0081] Analyze the forces on the numbered sub - regions in turn according to the multiplication rule, and then combine with the sliding ability under its own weight to generate the slope comprehensive sliding index XZX after synthesis. i ;

[0082] The slope comprehensive anti - sliding index XZK i is used to reflect the comprehensive value of the anti - sliding ability of the i - th sub - region itself and the anti - sliding ability caused by the action of other upper - side sub - regions. The slope comprehensive sliding index XZX i is used to reflect the comprehensive value of the sliding ability of the i - th sub - region itself and the sliding ability caused by the action of other upper - side sub - regions. The slope comprehensive anti - sliding index XZK i The larger the value of i the stronger the anti - sliding ability. The larger the value of the slope comprehensive sliding index XZX

[0083] Step 6. Conduct a correlation analysis on the slope comprehensive anti - sliding index XZK i and the slope comprehensive sliding index XZX i to generate the slope warning coefficient Δ, compare the slope warning coefficient Δ with the threshold ε, and output the warning level.

[0084] Conduct a correlation analysis on the slope comprehensive anti - sliding index XZK i and the slope comprehensive sliding index XZX i to generate the slope warning coefficient Δ i , and the formula is:

[0085]

[0086] The slope warning coefficient Δ iUsed to reflect the ratio of the sliding-down ability to the anti-sliding ability of the \(i\)th sub-region. By comparing the anti-sliding displacement ability and the sliding-down displacement ability of the \(i\)th sub-region, it is determined whether the sub-region has the risk of landslide. The larger the value of the slope warning coefficient, the greater the sliding-down risk of the sub-region compared to the anti-sliding ability, indicating a greater risk of landslide in the sub-region. The threshold \(\varepsilon\) is set to 1. When \(\Delta\) i \(\geq\varepsilon\), the first-level rainfall warning alarm is triggered. At this time, the probability of landslide in the corresponding sub-region is extremely high, and corresponding measures need to be taken, which can be increasing support, repairing the slope, etc.; when \(\varepsilon / 2 < \Delta\) i \(<\varepsilon\), the second-level rainfall warning alarm is triggered. At this time, there is a certain probability of landslide in the corresponding sub-region, and it needs to be monitored and fed back in a timely manner. When \(\Delta\) i \(\leq\varepsilon / 2\), the rainfall warning alarm is not triggered.

[0087] The present invention divides the slope, analyzes the force on each slope, and analyzes it from the aspect of the force field. At the same time, in combination with the change in water content caused by rainfall, the slope warning coefficient \(\Delta\) i is output in real time to warn of the risk of landslide displacement in the corresponding sub-region.

[0088] The above formulas are all dimensionless and take their numerical values for calculation. The formula is obtained by collecting a large amount of data and performing software simulation to obtain a formula closest to the actual situation. The preset parameters in the formula are set by those skilled in the art according to the actual situation.

[0089] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. Those skilled in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or by a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software methods depends on the specific application and design constraints of the technical solution.

[0090] The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, and may be located in one place, or may be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0091] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application, and all should be covered within the protection scope of this application.

Claims

1. A rainfall-induced landslide warning method based on multi-field coupling, which is based on the coupled analysis of the force field and rainfall, and is characterized in that The specific steps include: S1. Divide the slope into N sub-regions from top to bottom equally, number the sub-regions, and collect the soil parameters of the sub-regions. The soil parameters include volumetric water content, soil saturated volumetric water content, volume, soil cohesion, water influence coefficient, and soil unit weight. S2. Conduct a correlation analysis on the soil parameters to generate the soil weight and effective cohesion. The soil weight is the gravity of the sub-region, and the effective cohesion is the cohesion of the sub-region considering the influence of water. S3. Collect the initial water content and initial internal friction angle of each sub-region, conduct a correlation analysis on the initial internal friction angle, initial water content, and volumetric water content to generate the real-time internal friction angle. The real-time internal friction angle is used to reflect the estimated value of the real-time internal friction angle of the slope during rainfall. Conduct a correlation analysis on the real-time internal friction angle to generate the pressure coefficient. The pressure coefficient is used to reflect the degree of pressure influence of the i-1 sub-region on the current sub-region. S4. Conduct a correlation analysis on the soil weight, volume, and effective cohesion to generate the anti-sliding force of the slope. Conduct a correlation analysis on the soil weight and slope inclination angle to generate the sliding force of the slope. The anti-sliding force of the slope is used to reflect the anti-sliding ability of the slope, and the sliding force of the slope is used to reflect the sliding force of the slope. S5. Conduct a correlation analysis on the anti-sliding force of the slope and the pressure coefficient to generate the comprehensive anti-sliding index of the slope. The comprehensive anti-sliding index of the slope is used to reflect the anti-sliding degree of the current sub-region obtained by considering the forces of other sub-regions. Conduct a correlation analysis on the sliding force of the slope and the pressure coefficient to generate the comprehensive sliding index of the slope. The comprehensive sliding index of the slope is used to reflect the sliding force condition of the current sub-region obtained by considering the forces of other sub-regions. S6. Analyze the correlation between the comprehensive anti-sliding index XZK of the slope i and the comprehensive sliding index XZX of the slope i to generate a slope warning coefficient Δ, compare the slope warning coefficient Δ with the threshold ε, and output the warning level.

2. The rainfall-induced landslide warning method based on multi-field coupling according to claim 1, characterized in that: The subscript i is used to index the sub-regions, and the volumetric water content θ of the soil in the i-th sub-region is monitored in real time by a soil moisture sensor. i , and the saturated volumetric water content of the soil in the i-th sub-region is measured by the immersion method. For the volumetric water content θ i and the saturated volumetric water content of the soil a correlation analysis is performed to generate the soil saturation S i , and the formula used is: Soil saturation S i is the volumetric water content of the soil in the i-th sub-region.

3. The rainfall-induced landslide warning method based on multi-field coupling according to claim 2, characterized in that: Volume V i is the volume of the i-th sub-region. For the soil saturation S i , volume V i a correlation analysis is performed to generate the soil weight W of the i-th sub-region i , and the formula used is: Among them, is the unit weight of dry soil in the i-th sub-region, which is measured through experiments. is the unit weight of water. The soil weight W of the i-th sub-region i is used to reflect the gravity of the slope sub-region considering moisture. Soil cohesion c i is the initial cohesion of the soil in the i-th sub-region, measured through experiments. The moisture influence coefficient k is a coefficient used to reflect the influence of soil moisture on cohesion, measured through soil shear experiments. For soil cohesion c i , moisture influence coefficient k, and soil saturation S i a correlation analysis is carried out to generate the effective cohesion The formula based on is: Effective cohesive force It is the cohesive force of the soil in the i-th sub-region considering the influence of soil moisture.

4. A rainfall-induced landslide warning method based on multi-field coupling according to claim 3, characterized in that: Initial internal friction angle Initial water content is the internal friction angle and water content when there is no rainfall in the i-th sub-region. For the initial internal friction angle Initial water content and volumetric water content θ i perform a correlation analysis to generate the real-time internal friction angle The formula based on is as follows: b is the sensitivity coefficient of the internal friction angle to the change in water content, and the real-time internal friction angle is used to reflect the estimated value of the real-time internal friction angle of the slope during rainfall; Perform a correlation analysis on the real-time internal friction angle to generate the pressure coefficient μ i , and the formula used is: where, β i is the inclination angle of the i-th sub-region, and β i-1 is the inclination angle of the (i - 1)-th sub-region, and the pressure coefficient is used to reflect the degree of pressure influence of the (i - 1)-th sub-region on the i-th sub-region.

5. A rainfall-induced landslide warning method based on multi-field coupling according to claim 4, characterized in that: For the soil weight W i , volume V i and effective cohesive force carry out a correlation analysis to generate the anti-sliding force XK of the slope i , and the formula is as follows: For the soil weight W i and the slope inclination angle β i perform a correlation analysis to generate the slope sliding force XX i , and the formula is as follows: XX i = W i * sinβ i Among them, the anti-sliding force XK of the slope i is used to reflect the anti-sliding ability of the i-th sub-region affected by itself, and the slope sliding force XX i is used to reflect the sliding ability of the i-th sub-region affected by itself.

6. The rainfall-induced landslide warning method based on multi-field coupling according to claim 5, characterized in that: The anti-sliding force XK of the slope i and the pressure coefficient μ i are subjected to correlation analysis to generate the comprehensive anti-sliding index XZK of the slope i , and the formula is as follows: Conduct a correlation analysis on the slope downsliding force and the pressure coefficient to generate the slope comprehensive downsliding index XZX i , and the formula relied on is as follows: Slope comprehensive anti-sliding index XZK i The slope comprehensive anti-sliding index XZK, which is used to reflect the comprehensive value of the anti-sliding ability of the i-th sub-region itself and the anti-sliding ability caused by the action of other upper sub-regions i It is used to reflect the comprehensive value of the sliding ability of the i-th sub-region itself and the sliding ability caused by the action of other upper sub-regions.

7. A rainfall-induced landslide warning method based on multi-field coupling according to claim 1, characterized in that: For the comprehensive anti-sliding index XZK of the slope i and the comprehensive sliding index XZK of the slope i perform a correlation analysis to generate the slope warning coefficient Δ i , and the formula relied on is: Slope warning coefficient Δ i It is used to reflect the ratio of the sliding ability to the anti-sliding ability of the i-th sub-region. The threshold ε is set to 1. When Δ i ≥ε, the first-level rainfall warning alarm is triggered. At this time, the probability of landslide in the corresponding sub-region is extremely high, and corresponding measures need to be taken; when ε / 2 < Δ i <ε, the second-level rainfall warning alarm is triggered. At this time, there is a certain probability of landslide in the corresponding sub-region, and it needs to be monitored and fed back in a timely manner. When Δ i ≤ε / 2, the rainfall warning alarm is not triggered.

Images