Slope support scheme evaluation method and system

Abstract

The invention provides a slope support scheme evaluation method and system, and is suitable for the technical field of slope support. The method comprises the steps of index determination, index weight calculation, index scoring and comprehensive score calculation, and a comprehensive slope support scheme evaluation system is constructed by combining multi-dimensional indexes. Geotechnical parameters are dynamically adjusted by adopting a strength reduction method, a relation between slope crest displacement and a safety coefficient is fitted through an objective function, an optimization algorithm is started to accelerate convergence after a polynomial curve is generated by introducing pre-iteration, and the problems that time is consumed when multiple schemes are compared and selected, and safety coefficient calculation consumes much time are solved. A construction difficulty index and a surrounding environment-friendly degree index are quantified, and related parameters are input through a system for automatic scoring.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of slope support, in particular to a slope support scheme evaluation method and system. BACKGROUND

[0002] The slope support project is facing double tests: ensuring the safety and stability of the structure, and considering the protection of the ecological environment. At present, the evaluation system for selecting slope support in the industry mainly focuses on the safety factor, economic cost and construction period, but this mode has limitations that cannot be ignored. On the one hand, the traditional evaluation index dimension is difficult to match the emerging green construction concept, and the key factors related to sustainable development such as carbon emissions and environmental disturbance degree are not considered; on the other hand, the existing evaluation methods mostly rely on the subjective experience of experts to allocate weights, which not only makes the evaluation process have strong subjective color, but also lacks scientific and rigorous quantitative verification mechanism. Especially in dealing with qualitative indexes such as construction difficulty and environmental friendliness, the existing method often appears to be vague, which is easy to cause the deviation of the final evaluation result from the actual situation of the project.

[0003] Therefore, a full-factor evaluation framework is needed to make up for the lack of traditional methods in the sustainable development dimension, while minimizing the impact of human factors on the evaluation results and realizing automatic slope support scheme evaluation. SUMMARY

[0004] The purpose of the present application is to solve the problems of traditional slope support scheme evaluation methods, such as strong subjectivity, great influence of individual factors and one-sided evaluation factors. A slope support scheme evaluation method and system are proposed to significantly improve the objectivity and engineering applicability of slope support scheme evaluation. At the same time, each quantitative index can realize the automation of slope support scheme evaluation, and can be widely applied in the technical field of slope support.

[0005] To achieve the above purpose, the present application provides the following technical scheme:

[0006] A slope support scheme evaluation method, specifically comprising the following steps:

[0007] S1, determining the index, determining the index of slope support scheme evaluation according to the selected scheme of slope support, the index including safety factor index, engineering cost index, construction period index, post-maintenance cost index, environmental friendliness index, carbon emission index and construction difficulty index;

[0008] S2, each index weight calculation, using analytic hierarchy process to determine each index weight, using the value in 1-9 interval to pair each index importance score, build comparison matrix, calculate comparison matrix each column normalization and, get the normalization matrix, get each index weight by calculating the average value of each row of the normalization matrix, then perform consistency check, through the weight of each index determined as each index weight, not through then re-perform importance score and calculate the weight of each index according to the new comparison matrix;

[0009] S3, each index score, quantize construction difficulty index and the degree of friendly to the surrounding environment index, the quantized construction difficulty index and the degree of friendly to the surrounding environment index are scored using minimum maximum normalization, the safety factor index, the engineering cost index, the construction period index, the post-maintenance cost index and the carbon emission are all scored using the minimum maximum normalization;

[0010]

[0011] In the formula, S i,j The jth index value of the ith selected scheme, j=1, 2, 3, 4, 5, 6, 7 respectively correspond to the safety factor index, the engineering cost index, the construction period index, the post-maintenance cost index, the degree of friendly to the surrounding environment index, the carbon emission index and the construction difficulty index, S max,j The maximum value of the jth index in each selected scheme, S min,j The minimum value of the jth index in each selected scheme;

[0012] S4, comprehensive score calculation, according to the score of each index of each selected scheme, the comprehensive score is the weight and sum of each index score,

[0013]

[0014] In the formula, w j The weight of the jth index.

[0015] As a preferred technical scheme of the present application, the safety factor is calculated according to the strength reduction method combined with finite element software, including establishing a finite element model, introducing a strength reduction formula, defining stability judgment basis, introducing an iterative optimization algorithm, instability judgment and post-processing;

[0016] The establishment of the finite element model includes establishing a finite element model according to the geometric shape of the slope, the stratum distribution information, inputting the initial strength parameters of the rock-soil body, setting displacement constraints according to the selected scheme of slope support, setting loads and meshing;

[0017] The introduction of the strength reduction formula includes reducing the cohesion c and the internal friction angle φ in the initial strength parameters of the rock-soil body by a reduction factor Fs Step by step reduction, by adjusting F s Make the slope to the critical state of instability, the specific reduction function is

[0018]

[0019] In the formula, c'-reduced cohesion, φ'-reduced internal friction angle;

[0020] The definition of stability judgment basis, including the selection of slope displacement as the target function of adjusting F s The slope displacement threshold value is set, and the slope displacement threshold value and the convergence of finite element calculation results are used as the judgment basis of slope stability, and the target function is

[0021]

[0022] In the formula, u-slope displacement, a, b, c, d, e, f-polynomial curve fitting coefficients;

[0023] The introduction of iterative optimization algorithm, including setting the initial reduction coefficient F s (0) =1.0, set the convergence tolerance ∈, and then use the finite element software to calculate the slope displacement until the slope displacement exceeds the slope displacement threshold value or the calculation result does not converge, the first iteration is carried out by finite element calculation according to the initial reduction coefficient, and the slope displacement u1 without reduction is obtained, the second to sixth iterations use a fixed small step δ to reduce the iteration of the reduction coefficient, that is, F s (k) =F s (k-1) +δ, then carry out finite element calculation, and get the iteration of the slope displacement u2, u3, u4, u5, u6, F s (1) , F s (2) , F s (3) , F s (4) , F s (5) , F s (6) Substitute the target function to get the values of polynomial curve fitting coefficients a, b, c, d, e, f, and then start from the seventh iteration to use the accelerated iteration based on optimization algorithm to calculate the safety factor, and the steps of accelerated iteration are as follows:

[0024] 1) Calculate the reduction coefficient, according to the target function, calculate the reduction coefficient F s (k-1)Update the cohesion c′ and internal friction angle φ′ in the initial strength parameters, perform finite element calculations, and obtain the slope crest displacement u after iteration. k-1 ;

[0025] 2) Fit the objective function: Fit the objective function based on all reduction coefficients and slope top displacements from the first to the kth iteration to obtain the objective function for the next iteration;

[0026] The instability judgment and post-processing include, when the calculation result does not converge, the technicians analyze the degree of plasticity of the plastic zone to determine whether the calculation has failed to converge prematurely. If it has failed to converge prematurely, the technicians manually adjust the reduction coefficient and perform finite element iterative calculation again until the slope top displacement exceeds the slope top displacement threshold or the calculation result no longer fails to converge prematurely. The current reduction coefficient is recorded and is the safety factor.

[0027] As a preferred technical solution of the present invention, the quantitative indicator of environmental friendliness includes a comprehensive consideration of four aspects: noise, dust, vibration, and the distance of the nearest building from the construction site. Among these, noise, dust, and vibration exceed a threshold TE. j(j＝1,2,3) At that time, the corresponding score SE j(j＝1,2,3) All scores are the lowest possible scores, and they are not greater than the threshold TE. j(j＝1,2,3) At that time, the corresponding score SE j(j＝1,2,3) The score increases as noise, dust, and vibration decrease; the specific expression for the score is:

[0028]

[0029] In the formula, SE represents the scores for noise, dust, and vibration, with j = 1, 2, and 3 corresponding to noise, dust, and vibration respectively; ME represents the measured values ​​of noise, dust, and vibration; and TE represents the threshold values ​​for noise, dust, and vibration. The score SE4 is the lowest when the distance between the nearest building and the construction site is less than the threshold TE4. When the distance is not less than the threshold TE4, the score SE4 increases with the increase of the distance. The specific expression for the score is as follows:

[0030]

[0031] In the formula, ME4 represents the measured distance of the nearest building from the construction site; WE represents the weighted average distance of the nearest building from the construction site, taking into account noise, dust, vibration, and other factors. j(j＝1,2,3,4) Subsequently, quantitative results were obtained for the indicators of the degree of friendliness towards the surrounding environment.

[0032]

[0033] In the formula, i represents the i-th candidate solution.

[0034] As a preferred technical scheme of the present application, the construction difficulty index is quantified by expert scoring, and the simpler the supporting scheme is, the higher the score is, and the expert score of the single supporting scheme is the difficulty score of the selected scheme, and the difficulty score of the combined selected scheme is determined according to the single supporting scheme with the highest difficulty.

[0035] As a preferred technical scheme of the present application, the carbon emission calculation of the carbon emission index includes using the life cycle assessment method to calculate from the aspects of material production, transportation and construction, counting the material consumption, mechanical shift number and transportation distance, and calculating the carbon emission according to the emission factor obtained from the database.

[0036] A slope supporting scheme evaluation system applied to the slope supporting scheme evaluation method, comprising a project definition module, an index definition module, an index weight calculation module, an environment-friendly degree index quantification module, a construction difficulty index quantification module, a safety factor calculation module, a carbon emission calculation module, a comprehensive module, a scheme comprehensive score calculation module and a function expansion module.

[0037] The project definition module is used for new projects, and each project comprises a corresponding index definition module, an index weight calculation module, an environment-friendly degree index quantification module, a construction difficulty index quantification module, a safety factor calculation module, a carbon emission calculation module, a comprehensive module, a scheme comprehensive score calculation module and a function expansion module.

[0038] The index definition module is used for adding or deleting the indexes of the slope supporting scheme evaluation.

[0039] The index weight calculation module is used for inputting and saving the importance scores of each pair of indexes, and calculating the weights of the indexes according to the analytic hierarchy process.

[0040] The environment-friendly degree index quantification module is used for inputting and saving the noise, dust, vibration and data of the nearest building in use of each selected scheme, and calculating the quantification results of the environment-friendly degree indexes of each scheme.

[0041] The construction difficulty index quantification module is used for inputting and saving the difficulty scores of each selected scheme.

[0042] The safety factor calculation module is used for inputting and saving the geometric shape, stratum distribution information, initial strength parameters of rock and soil body and slope top displacement threshold value of the slope, controlling the reduction coefficient value through an iterative optimization algorithm, outputting to a finite element software for calculation, and obtaining and saving the corresponding slope top displacement calculation results.

[0043] The carbon emission calculation module is used for inputting and saving the material consumption, the mechanical shift number, and the transportation distance corresponding to each to-be-selected scheme, and calculating the carbon emission in combination with the emission factor in the database;

[0044] The comprehensive module is used for inputting and saving the engineering cost, the construction period, and the later maintenance cost of each to-be-selected scheme.

[0045] The scheme comprehensive score calculation module is used for calculating and saving the scores of each index, and calculating the comprehensive score of each to-be-selected scheme according to the weight of each index score.

[0046] The function expansion module is used for expanding the function of the index of the slope support scheme evaluation.

[0047] The beneficial effects of the present application are: 1. A comprehensive slope support scheme evaluation system is constructed in combination with multi-dimensional indexes; 2. The strength reduction method is used to dynamically adjust the geotechnical parameters, the relationship between the slope top displacement and the safety factor is fitted through the objective function, the optimization algorithm is started to accelerate the convergence after the polynomial curve is generated through 6 pre-iterations, and the problem of time-consuming safety factor calculation in the multi-scheme comparison is solved; 3. The construction difficulty index and the index of the degree of friendliness to the surrounding environment are quantified, and the related parameters are input by the system to automatically score. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 It is the flow chart of the slope support scheme evaluation method of the present application;

[0049] Figure 2 It is the structural schematic diagram of the slope support scheme evaluation system of the present application. DETAILED DESCRIPTION

[0050] The specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments given here are only for the purpose of description and explanation of the present application, and cannot be used to limit the present application. It should be noted that in the following description, many specific details are set forth in order to fully understand the present application, however, the present application can also have other implementation manners and deformations, therefore, the protection scope of the present application is not limited by the specific embodiments disclosed below.

[0051] In example one, the slope support scheme evaluation method is as follows:

[0052] S1, determining indexes;

[0053] The indexes of the slope support scheme evaluation are determined according to the to-be-selected scheme of the slope support, and the indexes include the safety factor index, the engineering cost index, the construction period index, the later maintenance cost index, the degree of friendliness to the surrounding environment index, the carbon emission index, and the construction difficulty index;

[0054] S2, index weight calculation;

[0055] The analytic hierarchy process is used to determine the weight of each index, and the values in the interval of 1-9 are used to score the importance of each index pair, 1 means that two indexes are equally important, 3 means that one index is slightly more important than the other, 5 means that one index is obviously more important than the other, 7 means that one index is much more important than the other, 9 means that one index is extremely more important than the other, and 2, 4, 6, 8 represent intermediate values between the above numbers; C1, C2, C3, C4, C5, C6, C7 respectively represent the safety coefficient index, the engineering cost index, the construction period index, the post-maintenance cost index, the degree of friendliness to the surrounding environment index, the carbon emission index and the construction difficulty index, and the importance score of each index pair in this embodiment is shown in Table 1,

[0056] Table 1: Importance score of each index pair

[0057] Indicators [C1] [C2] [C3] [C4] [C5] [C6] [C7] [C2] 1 1 3 2 5 4 6 3 [C2] 1 / 3 1 1 / 2 2 1 / 2 3 1 [C3] 1 / 2 2 1 3 1 4 2 [C4] 1 / 5 1 / 2 1 / 3 1 1 / 4 2 1 / 2 [C5] 1 / 4 2 1 4 1 5 2 [C6] 1 / 6 1 / 3 1 / 4 1 / 2 1 / 5 1 1 / 3 [C7] 1 / 3 1 1 / 2 2 1 / 2 3 1

[0058] A comparison matrix is constructed,

[0059]

[0060] The normalized sum of each column of the comparison matrix is calculated, and each element of the comparison matrix is divided by the normalized sum of the column in which the element is located to obtain a normalized matrix,

[0061]

[0062] The average value of each row of the normalized matrix is calculated to obtain the weight of each index, and the weights of C1, C2, C3, C4, C5, C6 and C7 are w1=0.34, w2=0.10, w3=0.18, w4=0.06, w5=0.18, w6=0.04 and w7=0.10 respectively;

[0063] Then, consistency check is performed, and if it is passed, the weight of each index obtained is determined as the weight of each index, and if it is not passed, the importance score is re-performed and the weight of each index is obtained according to the new comparison matrix;

[0064] S3, score each index;

[0065] The degree of friendliness to the surrounding environment index is quantified, including comprehensive consideration from four aspects of noise, dust, vibration and distance of the nearest building from the construction site, wherein when the noise, dust and vibration are greater than the threshold value TE j(j＝1,2,3) , the corresponding score SE j(j＝1,2,3) is the lowest score, and when it is not greater than the threshold value TE j(j＝1,2,3) , the corresponding score SE j(j＝1,2,3) increases with the decrease of noise, dust and vibration, and the specific expression of the score is

[0066]

[0067] In the formula, SE-noise, dust, vibration score, j=1, 2, 3 respectively corresponding to noise, dust, vibration, ME-noise, dust, vibration measured value, TE-noise, dust, vibration threshold; the distance between the nearest building and the construction site is less than the threshold TE4, and the corresponding score SE4 is the lowest score, and when not less than the threshold TE4, the corresponding score SE4 increases with the increase of the distance, and the specific expression of the score is

[0068]

[0069] In the formula, ME4-the measured value of the distance between the nearest building and the construction site; considering the corresponding weight WE of noise, dust, vibration, and the distance between the nearest building and the construction site j(j＝1,2,3,4) After that, the quantification result of the surrounding environment friendly degree index is obtained,

[0070]

[0071] In the formula, i-the ith selected scheme;

[0072] The construction difficulty index is quantified by expert scoring, and the simpler the supporting scheme, the higher the score. The expert score of the single supporting scheme is the difficulty score of the selected scheme, and the difficulty score of the combined selected scheme is determined according to the single supporting scheme with the highest difficulty. Since the difficulty of the supporting scheme has a certain relationship with the geological conditions of the project, but has little effect on the final evaluation result, a general expert scoring is adopted here. After the existing single supporting scheme is counted and scored, the supporting scheme can be reused after one expert scoring. The difficulty scores of different single supporting schemes are shown in Table 2.

[0073] The carbon emission calculation adopts the life cycle assessment method, and is calculated from three aspects of material production, transportation and construction. The material consumption, mechanical station number, transportation distance are counted, and the carbon emission calculation is carried out according to the emission factor obtained from the database. The carbon emission of material production C 材料 , the carbon emission of transportation C 运输 , the carbon emission of construction machinery C 机械 , and the carbon emission of power consumption C 电力 are respectively,

[0074] C 材料 =∑material consumption×material emission factor (6)

[0075] C 运输 =∑material weight×transportation distance×transportation emission factor (7)

[0076] C 机械 =∑Number of machine shifts × Emission factor per shift (8)

[0077] C 材料 =∑ Electricity consumption × Emission factor of regional power grid (9)

[0078] Table 2. Difficulty scores of different single-mode support schemes

[0079]

[0080] The quantified construction difficulty index and the environmental friendliness index are scored using the minimum-maximum normalization method. The safety factor index, project cost index, construction period index, post-maintenance cost index and carbon emissions are also scored using the aforementioned minimum-maximum normalization method.

[0081]

[0082] In the formula, S i,j - The j-th index value of the i-th candidate scheme, j = 1, 2, 3, 4, 5, 6, 7, corresponds to the safety factor index, project cost index, construction period index, post-maintenance cost index, environmental friendliness index, carbon emission index, and construction difficulty index, respectively.

[0083] S4. Calculation of overall score;

[0084] A comprehensive score is calculated based on the scores of each indicator for each candidate option. This comprehensive score is the weighted sum of the scores for each indicator.

[0085]

[0086] In the formula, w j - The weight of the j-th indicator.

[0087] In this embodiment, it is necessary to evaluate the safety factor index of many schemes. Conventional finite element iterative calculation takes a long time. After generating a polynomial curve through 6 pre-iterations, the optimization algorithm is started to accelerate convergence. Specifically, it includes establishing a finite element model, introducing a strength reduction formula, defining the stability judgment criteria, introducing an iterative optimization algorithm, instability judgment and post-processing.

[0088] Establish a finite element model based on the slope geometry and stratum distribution information. Input the initial strength parameters of the soil and rock mass, set displacement constraints according to the alternative slope support schemes, set loads, and mesh generation.

[0089] Introducing a strength reduction formula, the cohesion c and internal friction angle φ in the initial strength parameters of soil and rock are reduced by a reduction factor F. s Gradually reduce, by adjusting Fs , which makes the slope reach a critical state of instability, and the specific reduction function is

[0090]

[0091] where c' is the reduced cohesion, and φ' is the reduced internal friction angle.

[0092] The stability judgment basis is defined, and the displacement of the slope top is selected as the target function of adjusting F s , the slope top displacement threshold value is set, and the slope top displacement threshold value and the convergence of the finite element calculation result are used as the judgment basis of the slope stability, and the target function is

[0093] u(F s ) = a + bF s + cF s 2 + dF s 3 + eF s 4 + fF s 5 (14)

[0094] where u is the displacement of the slope top, and a, b, c, d, e, and f are polynomial curve fitting coefficients.

[0095] An iterative optimization algorithm is introduced, the initial reduction coefficient F s (0) = 1.0 is set, the convergence tolerance ∈ is set, then the finite element software is used to iteratively calculate the slope top displacement until the slope top displacement exceeds the slope top displacement threshold value or the calculation result does not converge, the first iteration is performed according to the initial reduction coefficient to obtain the slope top displacement u1 without reduction, and the second to sixth iterations use a fixed small step size δ to perform iterative reduction of the reduction coefficient, i.e. F s (k) = F s (k-1) + δ, then the finite element calculation is performed to obtain the iteratively calculated slope top displacement u2, u3, u4, u5, and u6, and u1, u2, u3, u4, u5, F s (1) , F s (2) , F s (3) , F s (4) , F s (5) , F s (6)Substitute the objective function, get the polynomial curve fitting coefficients a, b, c, d, e, f, and then start from the seventh iteration, the safety factor is calculated by using the optimization algorithm based on accelerated iteration, the steps of accelerated iteration are as follows:

[0096] 1) Calculate the reduction factor, calculate the reduction factor F of the kth iteration when the slope top displacement reaches the slope top displacement threshold value according to the objective function s (k-1) , update the cohesion c' and internal friction angle φ' in the initial strength parameter, perform finite element calculation, and obtain the slope top displacement u after iteration k-1 ;

[0097] 2) Fit the objective function, fit the objective function according to all the reduction factors and slope top displacements from the first to the kth iteration, and obtain the objective function of the next iteration;

[0098] Instability judgment and post-processing, when the calculation result does not converge, the technical personnel analyzes the degree of penetration of the plastic zone to judge whether the calculation is prematurely divergent, if it is prematurely divergent, the technical personnel manually adjusts the reduction factor, and then performs finite element iteration calculation again, until the slope top displacement exceeds the slope top displacement threshold value or the calculation result no longer prematurely diverges, records the current reduction factor, and the current reduction factor is the safety factor.

[0099] Example two, slope support scheme evaluation system, comprising:

[0100] Project definition module, used for new project, each project includes corresponding index definition module, index weight calculation module, surrounding environment friendly degree index quantification module, construction difficulty index quantification module, safety factor calculation module, carbon emission calculation module, comprehensive module, scheme comprehensive score calculation module and function expansion module;

[0101] Index definition module, used for adding and deleting indexes of slope support scheme evaluation;

[0102] Index weight calculation module, used for inputting and saving the importance score of each index pair, and calculating the weight of each index according to the analytic hierarchy process;

[0103] Surrounding environment friendly degree index quantification module, used for inputting and saving noise, dust, vibration, and data of the nearest building in use from the construction site of each selected scheme, and calculating the quantization result of the surrounding environment friendly degree index of each scheme;

[0104] Construction difficulty index quantification module, used for inputting and saving the difficulty score of each selected scheme;

[0105] A safety factor calculation module is configured to input and save the geometric shape of the slope, stratum distribution information, initial strength parameters of the rock-soil body, and a slope top displacement threshold value, control a reduction factor value through an iterative optimization algorithm, output to a finite element software for calculation, and obtain and save corresponding slope top displacement calculation results.

[0106] A carbon emission calculation module is configured to input and save the material usage, mechanical shift number, and transportation distance corresponding to each selected scheme, and calculate the carbon emission in combination with the emission factor in the database.

[0107] A comprehensive module is configured to input and save the engineering cost, construction period, and post-maintenance cost of each selected scheme.

[0108] A scheme comprehensive score calculation module is configured to calculate and save the score of each index, and calculate the comprehensive score of each selected scheme according to the weight of the score of each index.

[0109] A function expansion module is configured to add the function expansion of the index of the slope support scheme evaluation.

[0110] In summary, the slope support scheme evaluation method and system has the characteristics of comprehensive and objective evaluation, strong applicability, and automatic evaluation after inputting parameters in the field of slope support technology.

[0111] It should be understood that the above embodiments are one or more embodiments of the present application, and there are many other embodiments and variations based on the present application; the deformation and modification of the present application by ordinary technical personnel in the industry without making innovative changes all belong to the protection scope of the present application.

Claims

1. A method for evaluating slope protection schemes, characterized in that, Specifically, the following steps are included: S1. Determine the indicators: Based on the alternative slope protection schemes, determine the evaluation indicators for the slope protection schemes. The indicators include safety factor, engineering cost, construction period, post-maintenance cost, environmental friendliness, carbon emissions, and construction difficulty. S2. Calculate the weights of each indicator. Use the analytic hierarchy process (AHP) to determine the weights of each indicator. Use values ​​in the range of 1-9 to score the importance of each indicator in pairs. Construct a comparison matrix. Calculate the normalized sum of each column of the comparison matrix to obtain the normalized matrix. Calculate the average of each row of the normalized matrix to obtain the weight of each indicator. Then, perform a consistency check. If it passes, the weight of each indicator is determined as the weight of each indicator. If it fails, the importance score is recalculated and the weight of each indicator is obtained based on the new comparison matrix. S3. Scoring of each indicator, quantifying the construction difficulty indicator and the environmental friendliness indicator, and using the minimum-maximum normalization to score the quantified construction difficulty indicator and environmental friendliness indicator. The safety factor indicator, project cost indicator, construction period indicator, post-maintenance cost indicator and carbon emission are all scored using the aforementioned minimum-maximum normalization. In the formula, S i,j - The j-th index value of the i-th candidate scheme, where j = 1, 2, 3, 4, 5, 6, 7, corresponds to the safety factor, project cost, construction period, post-maintenance cost, environmental friendliness, carbon emissions, and construction difficulty index, respectively. max,j -The maximum value of the j-th indicator among all candidate solutions, S min,j -The minimum value of the j-th indicator among all candidate options; S4. Calculate the overall score: Based on the scores of each indicator for each candidate solution, calculate the overall score, which is the weighted sum of the scores of each indicator. In the formula, w j - The weight of the j-th indicator.

2. The slope protection scheme evaluation method according to claim 1, characterized in that: The safety factor is calculated using the strength reduction method combined with finite element software, including establishing a finite element model, introducing a strength reduction formula, defining the stability judgment criteria, introducing an iterative optimization algorithm, instability judgment and post-processing; The establishment of the finite element model includes establishing the finite element model based on the slope geometry and stratum distribution information, inputting the initial strength parameters of the soil and rock mass, setting displacement constraints based on the alternative slope support schemes, setting loads, and mesh generation. The introduced strength reduction formula includes reducing the cohesion c and internal friction angle φ in the initial strength parameters of the soil and rock mass by a reduction factor F. s Gradually reduce, by adjusting F s This causes the slope to reach a critical instability state, specifically the reduction function is... In the formula, c′ is the reduced cohesive force, and φ′ is the reduced internal friction angle; The defined stability judgment criteria include selecting the slope crest displacement as the adjustment F. s The objective function is defined as follows: a slope crest displacement threshold is set, and the convergence of the slope crest displacement threshold and the finite element calculation results is used as the criterion for judging slope stability. The objective function is... u(F s )=a+bF s +cF s 2 +dF s 3 +eF s 4 +fF s 5 (5) In the formula, u is the displacement at the top of the slope, and a, b, c, d, e, f are the polynomial curve fitting coefficients. The introduced iterative optimization algorithm includes setting an initial reduction coefficient F. s (0) =1.0, set the convergence tolerance ∈, and then use finite element software to iteratively calculate the slope crest displacement until the slope crest displacement exceeds the slope crest displacement threshold or the calculation result does not converge. The first iteration is performed using the initial reduction factor to obtain the slope crest displacement u1 before reduction. In the second to sixth iterations, a fixed small step size δ is used to iterate the reduction factor, i.e., F s (k) =F s (k-1) +δ, then perform finite element calculations to obtain the iterated slope top displacements u2, u3, u4, u5, u6, and F. s (1) F s (2) F s (3) F s (4) F s (5) F s (6) Substituting the values ​​of the objective function, we obtain the values ​​of the polynomial curve fitting coefficients a, b, c, d, e, and f. Then, starting from the seventh iteration, we use an accelerated iteration based on an optimization algorithm to calculate the safety factor. The accelerated iteration steps are as follows: 1) Calculate the reduction factor: Based on the objective function, calculate the reduction factor F for the k-th iteration when the slope crest displacement reaches the slope crest displacement threshold. s (k-1) Update the cohesion c′ and internal friction angle φ′ in the initial strength parameters, perform finite element calculations, and obtain the slope crest displacement u after iteration. k-1 ; 2) Fit the objective function: Fit the objective function based on all reduction coefficients and slope top displacements from the first to the kth iteration to obtain the objective function for the next iteration; The instability judgment and post-processing include, when the calculation result does not converge, the technicians analyze the degree of plasticity of the plastic zone to determine whether the calculation has failed to converge prematurely. If it has failed to converge prematurely, the technicians manually adjust the reduction coefficient and perform finite element iterative calculation again until the slope top displacement exceeds the slope top displacement threshold or the calculation result no longer fails to converge prematurely. The current reduction coefficient is recorded and is the safety factor.

3. The slope protection scheme evaluation method according to claim 1, characterized in that: The quantitative indicators of environmental friendliness are comprehensively considered from four aspects: noise, dust, vibration, and the distance of the nearest building from the construction site. Among these, noise, dust, and vibration exceeding the threshold TE are considered as environmental factors. j(j＝1,2,3) At that time, the corresponding score SE j(j＝1,2,3) All scores are the lowest possible scores, and they are not greater than the threshold TE. j(j＝1,2,3) At that time, the corresponding score SE j(j＝1,2,3) The score increases as noise, dust, and vibration decrease; the specific expression for the score is: In the formula, SE represents the scores for noise, dust, and vibration, with j = 1, 2, and 3 corresponding to noise, dust, and vibration respectively; ME represents the measured values ​​of noise, dust, and vibration; and TE represents the threshold values ​​for noise, dust, and vibration. The score SE4 is the lowest when the distance between the nearest building and the construction site is less than the threshold TE4. When the distance is not less than the threshold TE4, the score SE4 increases with the increase of the distance. The specific expression for the score is as follows: In the formula, ME4 represents the measured distance of the nearest building from the construction site; WE represents the weighted average distance of the nearest building from the construction site, taking into account noise, dust, vibration, and other factors. j(j＝1,2,3,4) Subsequently, quantitative results were obtained for the indicators of the degree of friendliness towards the surrounding environment. In the formula, i represents the i-th candidate solution.

4. The slope protection scheme evaluation method according to claim 1, characterized in that: The quantitative construction difficulty index is quantified by expert scoring, with simpler support schemes receiving higher scores. The expert score for a single-mode support scheme is the difficulty score for that candidate scheme, while the difficulty score for a combined-mode candidate scheme is determined by the single-mode support scheme with the highest difficulty.

5. The slope protection scheme evaluation method according to claim 1, characterized in that: The calculation of carbon emissions for the aforementioned carbon emission index includes using a life cycle assessment method to calculate from three aspects: material production, transportation, and construction. It involves statistical analysis of material usage, machine shifts, and transportation distance, and calculates carbon emissions based on emission factors obtained from a database.

6. A slope protection scheme evaluation system, applied in the slope protection scheme evaluation method as described in any one of claims 1 to 5, characterized in that: It includes a project definition module, an indicator definition module, an indicator weight calculation module, an indicator quantification module for the degree of friendliness to the surrounding environment, an indicator quantification module for the construction difficulty, a safety factor calculation module, a carbon emission calculation module, a comprehensive module, a scheme comprehensive score calculation module, and a function expansion module; The project definition module is used to create new projects. Each project includes a corresponding indicator definition module, indicator weight calculation module, environmental friendliness indicator quantification module, construction difficulty indicator quantification module, safety factor calculation module, carbon emission calculation module, comprehensive module, scheme comprehensive score calculation module, and function expansion module. The indicator definition module is used to add or delete indicators for evaluating slope protection schemes. The indicator weight calculation module is used to input and save the importance scores of each indicator in pairs, and to calculate the weight of each indicator according to the analytic hierarchy process. The module for quantifying the environmental friendliness index is used to input and save the noise, dust, vibration, and nearest-to-the-construction-site-occupying-building data for each candidate scheme, and to calculate the quantitative results of the environmental friendliness index for each scheme. The construction difficulty index quantification module is used to input and save the difficulty scores of each candidate scheme; The safety factor calculation module is used to input and save the slope's geometry, stratum distribution information, initial strength parameters of the soil and rock mass, and slope top displacement threshold. It also controls the reduction factor value through an iterative optimization algorithm, outputs it to the finite element software for calculation, and obtains and saves the corresponding slope top displacement calculation results. The carbon emission calculation module is used to input and save the material consumption, machine shifts, and transportation distance corresponding to each candidate scheme, and calculate the carbon emission in combination with the emission factors in the database. The integrated module is used to input and save the project cost, construction period, and subsequent maintenance cost of each candidate scheme; The comprehensive score calculation module is used to calculate and save the scores of each indicator, and calculate the comprehensive score of each candidate scheme according to the weight of each indicator score. The aforementioned functional expansion module is used to expand the functionality of adding indicators for evaluating slope protection schemes.

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