CN-122021139-A - Rainfall slope double failure judgment method and system considering parameter correlation

CN122021139ACN 122021139 ACN122021139 ACN 122021139ACN-122021139-A

Abstract

The invention discloses a rainfall slope double failure judging method and system considering parameter correlation, comprising the following steps of constructing a finite element slope model and simulating a slope rainfall and reduction process, constructing a random sample set considering the negative correlation of slope shear strength parameters and parameterizing rainfall working conditions, constructing a program script, realizing dynamic reduction of soil body material parameters along with time based on time increment and slope safety coefficient, calling an ABAQUS solver by using a powershell script to complete numerical calculation, dynamically calling a python script to conduct double failure judgment, finally extracting displacement and safety coefficient, outputting a calculation result, and analyzing the rainfall stability probability of the slope according to the result by staff. The invention can adaptively and accurately capture the critical moment of the acceleration instability transition of the soil body from the micro creep direction, simultaneously realize the large-scale random simulation of the working condition of the rainfall slope, and complete the high-efficiency, accurate and full-flow automatic output of the simulation sample.

Inventors

LIU QIANG
ZHANG ZHAOYU
SONG HUAIBO
ZHANG RUNHONG
WANG HAICHUAN
HU JINFENG

Assignees

西南交通大学

Dates

Publication Date: 20260512
Application Date: 20260116

Claims (10)

1. The rainfall slope double failure judging method considering parameter correlation is characterized by comprising the following steps of: Constructing a finite element slope model and simulating a slope rainfall and reduction process; Constructing a random sample set considering the negative correlation of the slope shear strength parameters, and parameterizing rainfall conditions; constructing a program script, and realizing dynamic reduction of soil body material parameters along with time based on the time increment and the slope safety coefficient; An ABAQUS solver is called by using a powershell script, calculation is submitted in a background silence mode, and after the calculation is completed, the powershell script dynamically calls a python script to perform double failure judgment based on rainfall displacement and dynamic response characteristics; and extracting displacement and safety coefficients, outputting a calculation result, and analyzing the probability of slope rainfall stability according to the result by a worker.
2. The method for determining double failure of a rainfall slope considering parameter correlation according to claim 1, wherein the process of simulating rainfall and reducing of the slope comprises the steps of: constructing a ground stress balance analysis step, and obtaining an initial stress state of a side slope; constructing a rainfall infiltration analysis step, and simulating pore water pressure change and slope deformation in the rainfall process; And constructing an intensity folding and subtracting method, namely judging the damage state of the slope, acquiring a safety coefficient, and writing initial conditions and field variables in the keywords.
3. The method for determining double failure of a rainfall slope considering parameter correlation according to claim 1, wherein the construction of the random sample set comprises the following steps: setting the average value, standard deviation, variation coefficient and correlation coefficient of the shear strength parameter cohesive force c and the internal friction angle phi of the side slope; construction of standard normal variables with correlation by linear transformation 、 ; Normal standard variable 、 Mapping back to the physical parameter space to obtain the first Grouping soil body parameter samples; And for each intensity group, generating M groups of soil body parameter samples with negative correlation in advance to form N multiplied by M slope rainfall stability analysis working conditions to be calculated.
4. The method for determining double failure of a rainfall slope considering parameter correlation according to claim 3, wherein the parameterized rainfall condition comprises the following steps: Determining rainfall interval during random slope rainfall simulation ]; Obtaining the first slope rainfall stability analysis working condition after linear dispersion Group rainfall intensity ; Aiming at different slopes of the finite element slope model, according to preset slopes and permeation proportion coefficients # ) Intensity of rainfall The flow boundary condition values of the surface pore fluid required for conversion to inp file.
5. The rainfall slope dual-failure determination method considering parameter correlation according to claim 1, wherein the specific flow of dynamic reduction of soil material parameters over time is as follows: search Range for setting slope safety coefficient Step size of intensity reduction ; Calculating the shear strength parameter after the reduction corresponding to each random sample; Reading an input inp file, and automatically positioning the inp file to soil mass material key definition fields of MohrCoulomb and MohrCoulombHardening through pointers; Writing the reduced shear strength parameters into MohrCoulomb and MohrCoulombHardening fields, and simultaneously establishing the time t and the safety coefficient of the analysis step The ABAQUS solver automatically reduces the shear strength parameters along the time axis when performing pseudo-static solutions.
6. The method for determining double failure of a rainfall slope with consideration of parameter correlation according to claim 5, wherein the shear strength parameters after the compromise are: cohesion after the reduction: Internal friction angle after the reduction: The mapping relation between the time t of the analysis step and the safety coefficient F is as follows: In the formula, Is the first A cohesive force; is the first Internal friction angles; Is a slope safety coefficient; Is the maximum value of the slope safety coefficient; Is the minimum value of the slope safety coefficient.
7. The method for determining double failure of a rainfall slope considering parameter correlation according to claim 1, wherein the double failure determination comprises the steps of: Checking maximum displacement of all nodes in rainfall analysis step If the value is larger than the set displacement threshold, if so, skipping the strength reduction stage, and recording the safety coefficient as ; If not, extracting a displacement-time course curve of a key node in the strength reduction analysis step, calculating a dynamic inflection point of the slope under a rainfall condition, capturing a destabilization inflection point of the slope through a judgment criterion, outputting a safety coefficient if the destabilization inflection point is the destabilization inflection point, and if not, continuing capturing by utilizing the judgment criterion until the completion.
8. The method for determining double failure of a rainfall slope considering parameter correlation according to claim 7, wherein the dynamic inflection point adopts the following calculation expression: Instantaneous displacement rate: rate increase ratio: In the formula, Is that Displacement at time; is the first Analog time corresponding to the incremental steps.
9. The method for determining double failure of a rainfall slope considering parameter correlation according to claim 7, wherein the determination criterion is; motion significance, namely, the current instantaneous displacement rate is larger than a set minimum instantaneous displacement rate threshold; rate increase mutation rate increase ratio is greater than a set rate increase ratio threshold; Displacement effectiveness: the moment displacement is greater than the minimum displacement threshold; if and only if the above conditions are satisfied at the same time, determining that The moment is the instability inflection point of the side slope.
10. A rainfall slope double failure determination system taking parameter correlation into consideration, which uses the method as claimed in any one of claims 1 to 9, and is characterized by comprising the following modules: The finite element model module is used for constructing a finite element slope model and simulating a slope rainfall and reduction process; The random sample set construction module is used for constructing a random sample set considering the negative correlation of the slope shear strength parameters and parameterizing rainfall conditions; the dynamic reduction module is used for constructing a program script and realizing the dynamic reduction of soil body material parameters along with time based on the time increment and the slope safety coefficient; And the automatic calculation module is used for calling an ABAQUS solver by using a powershell script, submitting calculation in a background silence mode, dynamically calling a python script to perform double failure judgment based on rainfall displacement and dynamic response characteristics after the calculation is completed, extracting displacement and safety coefficients, finally outputting a calculation result, and performing slope stability analysis by staff according to the output calculation result.

Description

Rainfall slope double failure judgment method and system considering parameter correlation Technical Field The invention relates to the technical field of computer and geotechnical engineering disaster prevention, in particular to a rainfall slope dual failure judgment method and system considering parameter correlation. Background Rainfall is a major factor in inducing slope destabilization in summer. The traditional slope stability analysis is mostly deterministic analysis, wherein the limit balance method is a main analysis means of engineering world for a long time, but ignores the stress-strain constitutive relation of the soil body, and cannot simulate the progressive damage process of the soil body. In addition, natural rock-soil mass has significant spatial variability, and uncertainty of rock-soil mass parameters is often ignored by deterministic analysis. At present, slope stability analysis based on probability theory gradually becomes the mainstream, and by considering variability of slope rock-soil parameters, a large amount of sample data is obtained by using finite element and Monte Carlo simulation, so that the rainfall failure probability of the slope is analyzed. In the theoretical research of random simulation, random finite element analysis based on Monte Carlo simulation provides powerful theoretical support for the research of the rainfall instability probability of the side slope, but some defects are often exposed in practical engineering application. The existing random finite element analysis often presumes the shear strength parameters (cohesive force c and internal friction angle phi) of the rock-soil body as mutually independent, simplifies the calculation process of slope rainfall instability, and further obtains efficient simulation. However, a large number of indoor and outdoor experiments and related studies indicate that there is a significant negative correlation between the side slope cohesion and the internal friction angle. Therefore, the slope rainfall instability probability random simulation is carried out by neglecting the negative correlation among the slope shear strength parameters, so that the generated result data always deviates from a real parameter distribution interval, the calculated failure probability deviates from a real result, and the failure probability of the slope rainfall cannot be accurately reflected. On a numerical tool of random simulation, finite element software such as ABAQUS provides a feasible means for slope rainfall failure probability research, but most finite element software lacks a module for representing safety coefficient randomness distribution. When intensity folding and subtracting method is adopted to calculate the safety coefficient and the randomness distribution of the slope rainfall, the finite element software is usually used for firstly performing rainfall infiltration analysis to obtain pore water pressure and deformation response, and then performing intensity folding and subtracting analysis after the completion, so as to further determine the slope rainfall instability condition. In this stability analysis mode, commonly used failure criteria such as "calculation non-convergence" are used as evaluation criteria, but non-convergence in the case of complex fluid-solid coupling analysis is often due to numerical problems, not real physical damage. By setting a certain fixed displacement threshold as the destabilization basis, false displacement misjudgment is also easy to be caused. Meanwhile, the finite element software solves the safety coefficient, and field variables are manually set in the software to indirectly realize strength reduction. Therefore, when the randomness of the slope cohesive force and the internal friction angle is considered by adopting Monte Carlo simulation, thousands of artificial parameter settings are often required to be carried out by the traditional simulation method so as to meet the distribution rule of the randomness of the slope parameters. Furthermore, in finite element software represented by ABAQUS, the results produced by a single simulation often require hundreds of megabytes or even several GB of memory space in the volume of the memory, which is a huge requirement for computer disk space. Therefore, the existing random simulation method for the slope rainfall failure probability in the prior art not only does not theoretically consider the negative correlation of the slope shear strength parameter, but also is unreasonable in judging the slope rainfall failure, and meanwhile, the simulation technology is low in processing efficiency and large in occupied memory, and the process of 'strength reduction' and the automatic processing of result data are difficult to realize at the same time. In view of the foregoing, there is a need to develop a slope rainfall failure simulation method and a random simulation system that can consider the negative correlation of the slope shear streng