Urban inland inundation drainage system transformation project analysis method

Abstract

The invention discloses an urban inland inundation drainage system transformation project analysis method in the technical field of urban drainage system transformation project evaluation. The method comprises the steps that evaluation indexes are acquired; the evaluation indexes are divided into extremely-large indexes and extremely-small indexes by taking reduction of urban waterlogging risks and reduction of economic investment as targets; performing forward processing on the extremely-small indexes to convert the extremely-small indexes into extremely-large indexes, and performing standardization processing on all the extremely-large indexes to obtain standardized evaluation indexes; obtaining an entropy weight according to the information entropy of the standardized evaluation index; and according to the entropy weight and the positive ideal solution and the negative ideal solution of the standardized evaluation index, obtaining the relative proximity between each urban waterlogging drainage system reconstruction project scheme and the ideal solution, and according to the relative proximity between each urban waterlogging drainage system reconstruction project scheme and the ideal solution, obtaining the reconstruction project scheme of each urban waterlogging drainage system. And determining an optimal urban inland inundation drainage system reconstruction project scheme. According to the method, the problems of unreasonable scheme formulation and insufficient objectivity of a traditional AHP weighting method in an urban inland inundation regulation project are solved.

Description

Technical Field

[0001] The invention relates to an analysis method for urban waterlogging drainage system reconstruction engineering, belonging to the technical field of urban drainage system reconstruction engineering evaluation. Background Art

[0002] The current status of drainage pipe network systems in various cities in China is not optimistic. The main reasons for this situation include several aspects: First, urbanization and ecological destruction: With the acceleration of urbanization, the urban area has expanded, and the original natural terrain and water system have been replaced by buildings and roads, which has reduced the natural infiltration and evaporation of rainwater and increased the surface runoff. In addition, the urban heat island effect has led to local climate changes, which may increase the intensity and frequency of rainfall and aggravate the problem of waterlogging. Second, insufficient construction of drainage systems: The construction standards of drainage systems in many cities are low and cannot meet the drainage needs under extreme weather conditions. There are many historical debts, the drainage network is not fully covered, and there are gaps in the network in some areas, which makes these areas prone to waterlogging when encountering heavy rainfall. Third, poor operation and maintenance of drainage facilities: Due to the lack of sufficient maintenance and capital investment, the existing drainage facilities are aging and damaged, the rainwater outlets are seriously blocked, and the water-passing capacity of the drainage pipes is reduced. This makes it difficult for the drainage system to operate normally even under rainfall conditions within the design standards. Urban waterlogging not only affects urban traffic and damages infrastructure, but may also destroy the ecological balance of the city, affect urban greening and water ecosystems, reduce the ecological service functions of the city, and may also cause public health problems and affect the quality of life of residents, becoming an important factor restricting the safe development of the city. At present, there is a lack of an objective and comprehensive evaluation method for evaluating complex urban waterlogging drainage system renovation projects.

[0003] Due to the low construction standards of drainage systems in cities across China and the serious lack of basic data on urban drainage systems, it is difficult to effectively manage and maintain them. Low impact development (LID) is a more advanced technology today. In areas dominated by rainwater runoff, low impact development (LID) facilities are deployed to reduce runoff flow, while pipeline modifications are implemented to enhance pipeline drainage capacity and reduce the risk of urban waterlogging. At present, the informatization of drainage systems is developing rapidly, and researchers at home and abroad have developed a variety of drainage system models, but there is a lack of a multi-objective comprehensive evaluation method for urban waterlogging drainage system modification programs.

[0004] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgement or any form of suggestion that the information constitutes the prior art already known to ordinary technicians in this field. Summary of the invention

[0005] The technical problem to be solved by the present invention is that the existing scheme formulation in the urban waterlogging control project is unreasonable and the traditional AHP weighting method is not objective enough.

[0006] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions.

[0007] The present invention provides an analysis method for urban waterlogging drainage system reconstruction engineering, comprising:

[0008] Obtain evaluation indicators, including flooded area, flooded area reduction rate, flooded depth, flooded depth reduction rate and project cost;

[0009] With the goal of reducing urban waterlogging risks and economic input, the evaluation indicators are divided into extremely large indicators and extremely small indicators;

[0010] Transform extremely small indicators into extremely large indicators through positive processing, and standardize all extremely large indicators to obtain standardized evaluation indicators;

[0011] According to the information entropy of the standardized evaluation index, calculation is performed to obtain the entropy weight;

[0012] According to the entropy weight and the positive ideal solution and the negative ideal solution of the standardized evaluation index, calculation is performed to obtain the relative closeness between each urban waterlogging drainage system reconstruction project plan and the ideal solution.

[0013] According to the relative closeness of each urban waterlogging drainage system reconstruction project plan to the ideal solution, the optimal urban waterlogging drainage system reconstruction project plan is determined.

[0014] Furthermore, the method for obtaining the evaluation index includes:

[0015] Input the urban waterlogging drainage system reconstruction project plan into the verified urban rainwater model, perform simulation operation, and output the urban waterlogging simulation prediction results;

[0016] Obtaining the flooded area, flooded area reduction rate, flooded depth, and flooded depth reduction rate from the urban waterlogging simulation prediction results;

[0017] According to the urban waterlogging drainage system reconstruction project plan, calculations are performed to obtain the project cost.

[0018] Furthermore, the verification method of the urban stormwater model includes:

[0019] Obtain historical data of urban waterlogging drainage system reconstruction projects as a validation set;

[0020] Configure the initial parameters of the urban stormwater model, including infiltration rate, soil saturated hydraulic conductivity, surface roughness, and pipe friction coefficient;

[0021] Repeat the following steps for multiple iterations until the similarity between the urban waterlogging simulation prediction results and the actual urban waterlogging observation results reaches a threshold, and the verified urban rainwater model is obtained:

[0022] Input the validation set into the urban rainwater model, perform simulation runs, and output the urban waterlogging simulation prediction results;

[0023] The simulation prediction results of urban waterlogging are compared with the actual urban waterlogging observation results corresponding to the historical scheme data of the urban waterlogging drainage system reconstruction project, and the parameters of the urban stormwater model are adjusted, including infiltration rate, soil saturated hydraulic conductivity, surface roughness, and pipe friction coefficient.

[0024] Furthermore, with the goal of reducing the risk of urban waterlogging and reducing economic investment, the evaluation indicators are divided into extremely large indicators and extremely small indicators, including:

[0025] The flooded area reduction rate and flooded depth reduction rate are divided into extremely large indicators;

[0026] The flooded area, project cost and flooded depth are divided into extremely small indicators.

[0027] Furthermore, the very small index is positively processed and converted into a very large index using the positive formula, and the positive formula is expressed as:

[0028] (1);

[0029] In the formula, represents the numerical positive result of the jth standardized evaluation index in the i-th urban waterlogging drainage system reconstruction project plan, represents the value of the jth standardized evaluation index in the i-th urban waterlogging drainage system reconstruction project plan, Indicates the maximum value of all evaluation indicators.

[0030] Furthermore, all extremely large indicators are standardized using a standardized formula to obtain standardized evaluation indicators. The standardized formula is expressed as:

[0031] (2);

[0032] In the formula, represents the jth standardized evaluation index in the i-th urban waterlogging drainage system reconstruction project plan, Indicates all indicator values ​​under a fixed indicator type The average value of Indicates all indicator values ​​under a fixed indicator type The standard deviation of .

[0033] In the formula, represents the jth standardized evaluation index in the i-th urban waterlogging drainage system reconstruction project plan, Indicates all indicator values ​​under a fixed indicator type The average value of Indicates all indicator values ​​under a fixed indicator type The standard deviation of .

[0034] Furthermore, the information entropy of the standardized evaluation index is calculated to obtain the entropy weight, wherein the calculation formula of the entropy weight is expressed as:

[0035] (3);

[0036] In the formula, Indicates The entropy weight of the standardized evaluation index is Indicates The information entropy of the standardized evaluation index is Represents the total number of standardized evaluation indicators.

[0037] Furthermore, according to the entropy weight and the positive ideal solution and the negative ideal solution of the standardized evaluation index, calculations are performed to obtain the relative closeness between each urban waterlogging drainage system reconstruction project plan and the ideal solution, including:

[0038] According to the entropy weight, the positive ideal solution and negative ideal solution of the standardized evaluation index are calculated;

[0039] According to the positive ideal solution, the distance between each urban waterlogging drainage system reconstruction project plan and the positive ideal solution is calculated to obtain the positive ideal solution distance;

[0040] According to the negative ideal solution, the distance between each urban waterlogging drainage system reconstruction project plan and the negative ideal solution is calculated to obtain the negative ideal solution distance;

[0041] According to the positive ideal solution distance and the negative ideal solution distance, the relative proximity between each urban waterlogging drainage system renovation project plan and the ideal solution is calculated, and the urban waterlogging drainage system renovation project plan with the greatest relative proximity is taken as the optimal urban waterlogging drainage system renovation project plan.

[0042] Furthermore, the distance formula of the positive ideal solution distance of the i-th urban waterlogging drainage system reconstruction project is expressed as:

[0043] (4);

[0044] Among them, the distance formula of the negative ideal solution distance of the i-th urban waterlogging drainage system reconstruction project is expressed as:

[0045] (5);

[0046] In the formula, represents the negative ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, represents the positive ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, represents the negative ideal solution of the jth standardized evaluation index, represents the positive ideal solution of the jth standardized evaluation index, It represents the product of the value of the jth standardized evaluation index and the entropy weight in the i-th urban waterlogging drainage system reconstruction project plan.

[0047] Furthermore, the relative closeness between each urban waterlogging drainage system reconstruction project plan and the ideal solution is calculated based on the positive ideal solution distance and the negative ideal solution distance, wherein the calculation formula of the relative closeness is expressed as:

[0048] (6);

[0049] In the formula, represents the relative closeness between the reconstruction scheme of the urban waterlogging drainage system in the ith city and the ideal solution, where , represents the negative ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, represents the positive ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, Represents the total number of urban waterlogging drainage system improvement project proposals.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] The present invention provides a comprehensive evaluation method for urban waterlogging drainage system reconstruction projects. By comprehensively considering multiple evaluation indicators such as flooded area, flooded area reduction rate, flooded depth, flooded depth reduction rate and project cost, based on the superiority and inferiority distance method, a multi-dimensional and quantitative evaluation of urban waterlogging drainage system reconstruction projects is achieved. The method provided by the present invention subdivides the evaluation indicators into extremely large indicators and extremely small indicators, and through forward processing and standardized processing, the consistency and comparability of the evaluation indicators are ensured, and the influence of subjective judgment on the evaluation results is effectively reduced. In addition, the present invention also uses information entropy to calculate the entropy weight, which not only reflects the objective importance of the evaluation indicators, but also avoids the subjectivity of artificially setting weights, making the evaluation results more objective and scientific. Finally, by calculating the relative proximity of each reconstruction plan to the ideal solution, the optimal urban waterlogging drainage system reconstruction project plan can be accurately and quickly determined, which provides strong technical support for urban waterlogging control and significantly improves the decision-making efficiency and effect of drainage system reconstruction projects.

[0052] In summary, the present invention solves the problems of unreasonable scheme formulation in existing urban waterlogging control projects and insufficient objectivity of traditional AHP weighting methods. It also solves the problem that urban waterlogging drainage system reconstruction projects are complex and difficult to evaluate, and makes up for the defect that urban waterlogging drainage systems are difficult to quantitatively evaluate due to uncertainty and lack of objectivity in the comprehensive evaluation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 It is a flow chart of an analysis method for urban waterlogging drainage system reconstruction project provided by an embodiment of the present invention;

[0054] Figure 2 It is a schematic diagram of a specific implementation process of an urban waterlogging drainage system reconstruction project analysis method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0055] The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations on the technical solution of the present invention. The embodiments of the present invention and the technical features in the embodiments may be combined with each other unless there is a conflict.

[0056] The term "and / or" is only a description of the association relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " generally indicates that the related objects are in an "or" relationship.

[0057] Example 1

[0058] like Figure 1 As shown, this embodiment introduces an analysis method for urban waterlogging drainage system reconstruction engineering, including:

[0059] Obtain evaluation indicators, including flooded area, flooded area reduction rate, flooded depth, flooded depth reduction rate and project cost.

[0060] Evaluation indicators are key parameters for determining and evaluating the effectiveness of urban waterlogging drainage system renovation projects. The flooded area and flooded depth are factors that directly affect the risk of waterlogging, and the flooded area reduction rate, flooded depth reduction rate and project cost directly affect the cost-effectiveness of the renovation project.

[0061] With the goal of reducing the risk of urban waterlogging and reducing economic investment, the evaluation indicators are divided into extremely large indicators and extremely small indicators.

[0062] Categorizing the impact directions of reducing waterlogging risks according to evaluation indicators can help simplify the analysis process and ensure that all evaluation indicators are optimized in the same direction, facilitating the unification of evaluation standards.

[0063] The extremely small indicators are positively processed and transformed into extremely large indicators, and all extremely large indicators are standardized to obtain standardized evaluation indicators.

[0064] Converting extremely small indicators into extremely large indicators can ensure that all evaluation indicators comply with the evaluation principle of "the bigger the better"; at the same time, standardizing all extremely large indicators can eliminate dimensional differences and improve the comparability between evaluation indicators, so that evaluation indicators of different dimensions and magnitudes can be evaluated under the same standard.

[0065] According to the information entropy of the standardized evaluation index, calculation is performed to obtain the entropy weight.

[0066] The entropy weight of each evaluation indicator is calculated using information entropy theory to reflect the importance and information content of each evaluation indicator in the evaluation process. This avoids the subjectivity of artificially setting weights, makes weight allocation more objective and scientific, and improves the accuracy and credibility of the evaluation results.

[0067] According to the entropy weight and the positive ideal solution and the negative ideal solution of the standardized evaluation index, calculations are performed to obtain the relative proximity of each urban waterlogging drainage system reconstruction project plan to the ideal solution.

[0068] Based on the entropy weight and standardized evaluation index, the distance between each urban waterlogging drainage system renovation project scheme and the positive ideal solution and the negative ideal solution is calculated, and the relative closeness of each scheme to the ideal solution is further obtained, which can intuitively reflect the degree of closeness between the ideal solution and the ideal state, and provide a basis for determining the optimal urban waterlogging drainage system renovation project scheme.

[0069] According to the relative closeness of each urban waterlogging drainage system reconstruction project plan to the ideal solution, the optimal urban waterlogging drainage system reconstruction project plan is determined.

[0070] The method provided by this implementation provides scientific decision-making support for urban waterlogging management, helps reduce waterlogging risks, and improves urban flood control and drainage capabilities.

[0071] Example 2

[0072] Based on the same inventive concept as Example 1, this example introduces an analysis method for urban waterlogging drainage system reconstruction engineering. Figure 2 As shown, the specific steps include:

[0073] Step 1: Collect basic data.

[0074] The basic data include the urban pipe network data and inspection well distribution of the assessment area in the city, urban topography, underlying surface, weather, and river water level. The urban pipe network data include pipe diameter, pipeline burial depth and slope.

[0075] Step 2: Build and verify the urban drainage model.

[0076] The urban drainage model in this embodiment adopts the urban stormwater model, and the parameters of the urban stormwater model are configured according to the characteristics and needs of the city and the basic data collected, including infiltration rate, soil saturated hydraulic conductivity, surface roughness, and pipe friction coefficient. According to the urban terrain data and the layout of the drainage network, the city is divided into multiple sub-catchment areas; the flow generation, confluence and drainage parameters are set for each sub-catchment area; the boundary conditions of the urban stormwater model and the initial conditions of the urban stormwater model are set, and the boundary conditions include external water sources and boundary flow; the initial conditions include initial soil moisture content and groundwater level.

[0077] The historical scheme data of the urban waterlogging drainage system reconstruction project and the actual urban waterlogging observation results corresponding to the historical scheme data of the urban waterlogging drainage system reconstruction project are obtained and divided into a training set and a validation set.

[0078] The training set is imported into the urban stormwater model using GIS technology. By simulating the urban waterlogging environment and conducting multiple iterative training, the urban waterlogging simulation prediction results are output, including the flooded area, flooded area reduction rate, flooded depth, and flooded depth reduction rate.

[0079] After obtaining the trained urban rain and flood model, the urban rain and flood model is verified. The verification method of the urban rain and flood model includes:

[0080] Configure the initial parameters of the urban stormwater model, including infiltration rate, soil saturated hydraulic conductivity, surface roughness, and pipe friction coefficient;

[0081] Repeat the following steps for multiple iterations until the similarity between the urban waterlogging simulation prediction results and the actual urban waterlogging observation results reaches a threshold, and the verified urban rainwater model is obtained:

[0082] Input the validation set into the urban rainwater model, perform simulation runs, and output the urban waterlogging simulation prediction results;

[0083] The simulation prediction results of urban waterlogging are compared with the actual urban waterlogging observation results corresponding to the historical scheme data of the urban waterlogging drainage system reconstruction project, and the parameters of the urban stormwater model are adjusted, including infiltration rate, soil saturated hydraulic conductivity, surface roughness, and pipe friction coefficient.

[0084] Step 3: Obtain evaluation indicators.

[0085] In this embodiment, the method for obtaining the evaluation index includes:

[0086] Input the urban waterlogging drainage system reconstruction project plan into the verified urban rainwater model, perform simulation operation, and output the urban waterlogging simulation prediction results;

[0087] From the urban waterlogging simulation prediction results, obtain the flooded area X1, the flooded area reduction rate X2, the project cost X3, the flooded depth X4, and the flooded depth reduction rate X5;

[0088] According to the urban waterlogging drainage system reconstruction project plan, calculations are performed to obtain the project cost.

[0089] Step 4: Divide the evaluation indicators into extremely large indicators and extremely small indicators.

[0090] The present invention aims to reduce the risk of urban waterlogging and reduce economic investment, and divides the evaluation indicators into extremely large indicators and extremely small indicators. According to the principle that the larger the extremely large indicator, the better, and the smaller the extremely small indicator, the better, the flooded area reduction rate X2 and the flooded depth reduction rate X5 are classified as extremely large indicators, and the flooded area X1, the project cost X3 and the flooded depth X4 are classified as extremely small indicators.

[0091] Step 5: Data normalization and standardization.

[0092] This embodiment performs positive processing on extremely small indicators to convert them into extremely large indicators, and performs standardization processing on all extremely large indicators to obtain standardized evaluation indicators.

[0093] This embodiment conducts source transformation analysis according to the transformation ideas of urban drainage systems. The specific measures of source transformation are low impact development (LID) transformation, including green roof transformation q1, permeable pavement transformation q2, and pipeline transformation q3. This embodiment includes a total of 95 different urban waterlogging drainage system transformation project schemes, including a single measure, a combination of two measures, and a combination of three measures. Some of the more prominent urban waterlogging drainage system transformation project schemes are evaluated below to select the optimal urban waterlogging drainage system transformation project scheme.

[0094] The evaluation index data of the above-mentioned prominent urban waterlogging drainage system reconstruction project schemes were obtained through the urban stormwater model, as shown in Table 1.

[0095]

[0096] Among them, the positive transformation formula is used to transform the extremely small index into an extremely large index through positive transformation, and the positive transformation formula is expressed as:

[0097] (1);

[0098] In the formula, represents the numerical positive result of the jth standardized evaluation index in the i-th urban waterlogging drainage system reconstruction project plan, represents the value of the jth standardized evaluation index in the i-th urban waterlogging drainage system reconstruction project plan, Indicates the maximum value of all evaluation indicators.

[0099] Among them, all extremely large indicators are standardized using a standardized formula to obtain standardized evaluation indicators, and the standardized formula is expressed as:

[0100] (2);

[0101] In the formula, represents the jth standardized evaluation index in the i-th urban waterlogging drainage system reconstruction project plan, Indicates all indicator values ​​under a fixed indicator type The average value of Indicates all indicator values ​​under a fixed indicator type The standard deviation of .

[0102] The results obtained after the numerical values ​​of the evaluation indicators of the above-mentioned prominent urban waterlogging drainage system renovation project schemes were normalized and standardized are shown in Table 2.

[0103]

[0104] Step 6: Calculate information entropy and entropy weight.

[0105] This embodiment uses the calculation formula of the entropy weight to perform calculation according to the information entropy of the standardized evaluation index to obtain the entropy weight.

[0106] Among them, the calculation formula of entropy weight is expressed as:

[0107] (3);

[0108] In the formula, Indicates The information entropy of the standardized evaluation index is: , represents the total number of urban waterlogging drainage system improvement project plans, represents the probability of the jth standardized evaluation index in the i-th urban waterlogging drainage system reconstruction project plan, where .

[0109] Among them, the calculation formula of entropy weight is expressed as:

[0110] (4);

[0111] In the formula, Indicates The entropy weight of the standardized evaluation index is Indicates The information entropy of the standardized evaluation index is Indicates the total number of standardized evaluation indicators. Entropy weight The larger the value, the greater the impact of the evaluation indicator on the comprehensive evaluation.

[0112] The calculation results of information entropy and entropy weight of the evaluation index obtained by the above process are shown in Table 3.

[0113]

[0114] Step 7: Calculate the ideal solution and distance.

[0115] In this embodiment, according to the entropy weight and the positive ideal solution and the negative ideal solution of the standardized evaluation index, calculation is performed to obtain the relative closeness between each urban waterlogging drainage system reconstruction project plan and the ideal solution, including:

[0116] According to the entropy weight, the positive ideal solution and negative ideal solution of the standardized evaluation index are calculated;

[0117] According to the positive ideal solution, the distance between each urban waterlogging drainage system reconstruction project plan and the positive ideal solution is calculated to obtain the positive ideal solution distance;

[0118] According to the negative ideal solution, the distance from each urban waterlogging drainage system reconstruction project plan to the negative ideal solution is calculated to obtain the negative ideal solution distance.

[0119] Among them, the distance formula of the positive ideal solution distance of the i-th urban waterlogging drainage system renovation project is expressed as:

[0120] (5);

[0121] Among them, the distance formula of the negative ideal solution distance of the i-th urban waterlogging drainage system reconstruction project is expressed as:

[0122] (6);

[0123] In the formula, represents the negative ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, represents the positive ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, represents the negative ideal solution of the jth standardized evaluation index, represents the positive ideal solution of the jth standardized evaluation index, It represents the product of the value of the jth standardized evaluation index and the entropy weight in the i-th urban waterlogging drainage system reconstruction project plan.

[0124] Step 8: Calculate relative proximity.

[0125] In this embodiment, the relative closeness between each urban waterlogging drainage system reconstruction project plan and the ideal solution is calculated based on the positive ideal solution distance and the negative ideal solution distance, wherein the calculation formula of the relative closeness is expressed as:

[0126] (7);

[0127] In the formula, represents the relative closeness between the reconstruction scheme of the urban waterlogging drainage system in the ith city and the ideal solution, where , represents the negative ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, represents the positive ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, Represents the total number of urban waterlogging drainage system improvement project proposals.

[0128] Among them, the relative closeness results of each urban waterlogging drainage system renovation project plan and the ideal solution are shown in Table 4.

[0129]

[0130] Step nine, determine the optimal urban waterlogging drainage system renovation project plan based on the relative proximity of each urban waterlogging drainage system renovation project plan to the ideal solution.

[0131] According to Table 4, the relative proximity results obtained in this embodiment are: Scheme 6>Scheme 12>Scheme 13>Scheme 20>Scheme 11>Scheme 14>Scheme 10>Scheme 19>Scheme 18>Scheme 9>Scheme 8>Scheme 7>Scheme 5>Scheme 3>Scheme 4>Scheme 17>Scheme 2>Scheme 1>Scheme 15>Scheme 16. The larger the relative proximity result, the better the urban waterlogging drainage system renovation project scheme. Therefore, Scheme 6 is the optimal urban waterlogging drainage system renovation project scheme. The optimal urban waterlogging drainage system renovation project scheme obtained by the superiority and inferiority distance method in this embodiment is more in line with the needs of actual engineering applications, and also avoids the problem of unreasonable evaluation results caused by imbalance of objective weights.

[0132] In summary, the present invention provides a comprehensive evaluation method for urban waterlogging drainage system reconstruction projects. By comprehensively considering multiple evaluation indicators such as flooded area, flooded area reduction rate, flooded depth, flooded depth reduction rate and project cost, based on the superiority and inferiority distance method, a multi-dimensional and quantitative evaluation of urban waterlogging drainage system reconstruction projects is achieved. The method provided by the present invention subdivides the evaluation indicators into extremely large indicators and extremely small indicators, and ensures the consistency and comparability of the evaluation indicators through forward processing and standardization processing, effectively reducing the influence of subjective judgment on the evaluation results. In addition, the present invention also uses information entropy to calculate the entropy weight, which not only reflects the objective importance of the evaluation indicators, but also avoids the subjectivity of artificially setting weights, making the evaluation results more objective and scientific. Finally, by calculating the relative proximity of each reconstruction plan to the ideal solution, the optimal urban waterlogging drainage system reconstruction project plan can be accurately and quickly determined, providing strong technical support for urban waterlogging control, and significantly improving the decision-making efficiency and effect of drainage system reconstruction projects.

[0133] The present invention solves the problems of unreasonable scheme formulation in existing urban waterlogging control projects and insufficient objectivity of traditional AHP weighting methods. It also solves the problem of complex and difficult evaluation of urban waterlogging drainage system reconstruction projects, and makes up for the defect that urban waterlogging drainage systems are difficult to quantitatively evaluate due to uncertainty and lack of objectivity in the comprehensive evaluation process.

[0134] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0135] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0136] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0137] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0138] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.

Claims

1. A method for analyzing urban waterlogging drainage system reconstruction projects, characterized in that: include: Obtain evaluation indicators, including flooded area, flooded area reduction rate, flooded depth, flooded depth reduction rate and project cost; With the goal of reducing urban waterlogging risks and economic input, the evaluation indicators are divided into extremely large indicators and extremely small indicators; Transform extremely small indicators into extremely large indicators through positive processing, and standardize all extremely large indicators to obtain standardized evaluation indicators; According to the information entropy of the standardized evaluation index, calculation is performed to obtain the entropy weight; According to the entropy weight and the positive ideal solution and the negative ideal solution of the standardized evaluation index, calculation is performed to obtain the relative closeness between each urban waterlogging drainage system reconstruction project plan and the ideal solution; According to the relative closeness of each urban waterlogging drainage system reconstruction project plan to the ideal solution, the optimal urban waterlogging drainage system reconstruction project plan is determined.

2. The urban waterlogging drainage system reconstruction engineering analysis method according to claim 1 is characterized in that: The method for obtaining the evaluation index includes: Input the urban waterlogging drainage system reconstruction project plan into the verified urban rainwater model, perform simulation operation, and output the urban waterlogging simulation prediction results; Obtaining the flooded area, flooded area reduction rate, flooded depth, and flooded depth reduction rate from the urban waterlogging simulation prediction results; According to the urban waterlogging drainage system reconstruction project plan, calculations are performed to obtain the project cost.

3. The urban waterlogging drainage system reconstruction engineering analysis method according to claim 2 is characterized in that: The verification method of the urban stormwater model comprises: Obtain historical data of urban waterlogging drainage system reconstruction projects as a validation set; Configure the initial parameters of the urban stormwater model, including infiltration rate, soil saturated hydraulic conductivity, surface roughness, and pipe friction coefficient; Repeat the following steps for multiple iterations until the similarity between the urban waterlogging simulation prediction results and the actual urban waterlogging observation results reaches a threshold, and the verified urban rainwater model is obtained: Input the validation set into the urban rainwater model, perform simulation runs, and output the urban waterlogging simulation prediction results; The simulation prediction results of urban waterlogging are compared with the actual urban waterlogging observation results corresponding to the historical scheme data of the urban waterlogging drainage system reconstruction project, and the parameters of the urban stormwater model are adjusted, including infiltration rate, soil saturated hydraulic conductivity, surface roughness, and pipe friction coefficient.

4. The urban waterlogging drainage system reconstruction engineering analysis method according to claim 2 is characterized in that: With the goal of reducing the risk of urban waterlogging and reducing economic investment, the evaluation indicators are divided into very large indicators and very small indicators, including: The flooded area reduction rate and flooded depth reduction rate are divided into extremely large indicators; The flooded area, project cost and flooded depth are divided into extremely small indicators.

5. The urban waterlogging drainage system reconstruction engineering analysis method according to claim 1 is characterized in that: Using the positive transformation formula, the extremely small index is positively processed and converted into an extremely large index. The positive transformation formula is expressed as: （1）； In the formula, represents the numerical positive result of the jth standardized evaluation index in the i-th urban waterlogging drainage system reconstruction project plan, represents the value of the jth standardized evaluation index in the i-th urban waterlogging drainage system reconstruction project plan, Indicates the maximum value of all evaluation indicators.

6. The urban waterlogging drainage system reconstruction engineering analysis method according to claim 5 is characterized in that: All extremely large indicators are standardized using the standardized formula to obtain standardized evaluation indicators. The standardized formula is expressed as: （2）； In the formula, represents the jth standardized evaluation index in the i-th urban waterlogging drainage system reconstruction project plan, Indicates all indicator values ​​under a fixed indicator type The average value of Indicates all indicator values ​​under a fixed indicator type The standard deviation of .

7. The urban waterlogging drainage system reconstruction engineering analysis method according to claim 1 is characterized in that: The information entropy of the standardized evaluation index is calculated to obtain the entropy weight, wherein the calculation formula of the entropy weight is expressed as: （3）； In the formula, Indicates The entropy weight of the standardized evaluation index is Indicates The information entropy of the standardized evaluation index is Represents the total number of standardized evaluation indicators.

8. The urban waterlogging drainage system reconstruction engineering analysis method according to claim 7 is characterized in that: According to the entropy weight and the positive ideal solution and the negative ideal solution of the standardized evaluation index, calculations are performed to obtain the relative closeness between each urban waterlogging drainage system reconstruction project plan and the ideal solution, including: According to the entropy weight, the positive ideal solution and negative ideal solution of the standardized evaluation index are calculated; According to the positive ideal solution, the distance from each urban waterlogging drainage system reconstruction project plan to the positive ideal solution is calculated to obtain the positive ideal solution distance; According to the negative ideal solution, the distance between each urban waterlogging drainage system reconstruction project plan and the negative ideal solution is calculated to obtain the negative ideal solution distance; According to the positive ideal solution distance and the negative ideal solution distance, the relative proximity between each urban waterlogging drainage system renovation project plan and the ideal solution is calculated, and the urban waterlogging drainage system renovation project plan with the greatest relative proximity is taken as the optimal urban waterlogging drainage system renovation project plan.

9. The urban waterlogging drainage system reconstruction project analysis method according to claim 8 is characterized in that: in, The distance formula of the positive ideal solution distance of the i-th urban waterlogging drainage system reconstruction project is expressed as: （4）； Among them, the distance formula of the negative ideal solution distance of the i-th urban waterlogging drainage system reconstruction project is expressed as: （5）； In the formula, represents the negative ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, represents the positive ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, represents the negative ideal solution of the jth standardized evaluation index, represents the positive ideal solution of the jth standardized evaluation index, It represents the product of the value of the jth standardized evaluation index and the entropy weight in the i-th urban waterlogging drainage system reconstruction project plan.

10. The urban waterlogging drainage system reconstruction engineering analysis method according to claim 9 is characterized in that: According to the positive ideal solution distance and the negative ideal solution distance, the relative closeness between each urban waterlogging drainage system reconstruction project plan and the ideal solution is calculated, wherein the calculation formula of the relative closeness is expressed as: （6）； In the formula, represents the relative closeness between the reconstruction scheme of the urban waterlogging drainage system in the ith city and the ideal solution, where , represents the negative ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, represents the positive ideal solution distance of the i-th urban waterlogging drainage system reconstruction project, Represents the total number of urban waterlogging drainage system improvement project proposals.

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