Method for dividing types and grades of structural defects of water supply pipeline

Abstract

The invention relates to a water supply pipeline structural defect type and grade division method, which comprises the following steps of: dividing various pipeline structural defects according to names and grades to obtain multiple grades and multiple names of pipeline structural defects; on the basis of the obtained pipeline structural defects of the multiple levels and the multiple names, the corresponding relation between each pipeline structural defect and the defect score, the pressure influence coefficient and the defect length influence coefficient is constructed; detecting the pipeline, assigning a detection result according to the corresponding relation, and calculating to obtain a structural defect state evaluation score and a pipe section structural defect density; and determining a water supply pipeline structural defect grade according to the structural defect state evaluation score, and determining a water supply pipeline structural defect type according to the structural defect density of the pipe section. The classification of the types and grades of the structural defects of the water supply pipeline is defined, errors caused by qualitative analysis are reduced, the damage condition of the water supply pipeline can be correctly evaluated, and a basis is provided for subsequent pipeline maintenance and repair.

Description

Technical Field

[0001] The present invention relates to the technical field of municipal pipeline defect monitoring, and in particular to a method for classifying types and grades of structural defects of water supply pipelines. Background Art

[0002] Water supply network is an important infrastructure on which urban development and production depend. With the development of global urbanization, more and more cities are facing challenges caused by leakage due to aging water supply facilities.

[0003] The leakage problem of water supply pipe network has been plaguing the entire water supply industry. According to relevant statistics, the current pipeline leakage rate in my country has generally reached 20% to 30%, and the average leakage rate in major cities has reached 40%, with an annual leakage volume of nearly 10 billion cubic meters. In addition to affecting the water quality and supply efficiency of urban water supply, aging and leakage of water supply pipes will also cause disasters such as urban road collapse, seriously affecting the lives of urban residents.

[0004] Therefore, aging and leakage of water supply pipelines are inevitable problems for future urban development. Pipeline defects are generally divided into structural defects and functional defects. Before repairing water supply pipelines, it is necessary to detect the status of defective pipelines through television detection, sonar detection, ultrasonic detection and other technologies, evaluate the status of pipelines based on the detection results, form a results report, and provide feasible suggestions for pipeline maintenance and repair.

[0005] In the prior art, there is a relatively complete technical standard system for drainage pipeline engineering inspection and evaluation. In the drainage pipeline evaluation system, drainage pipeline defects are classified by name, code, and grade. However, the prior art still lacks a method for classifying the types and grades of structural defects in water supply pipelines, which makes it difficult to correctly evaluate the damage status of water supply pipelines. Summary of the invention

[0006] In view of the problems existing in the prior art, the purpose of the present invention is to provide a method for classifying the types and grades of structural defects in water supply pipes, which can reduce the errors caused by qualitative analysis, is more conducive to the correct assessment of the damage condition of water supply pipes, and provides a reliable basis for subsequent pipeline maintenance and repair.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A method for classifying the types and grades of structural defects of a water supply pipeline comprises the following steps:

[0009] Various pipeline structural defects are divided according to names and levels, and pipeline structural defects with multiple levels and names are obtained;

[0010] Based on the obtained pipeline structural defects of multiple levels and multiple names, the corresponding relationship between each pipeline structural defect and the defect score, pressure influence coefficient, and defect length influence coefficient is established;

[0011] The damage condition of the pipeline to be tested is tested to obtain the test result containing the structural defects of the pipeline, and the test result is assigned a value according to the corresponding relationship to calculate the structural defect state assessment score F and the pipe section structural defect density D F ; Determine the structural defect level D of the water supply pipeline according to the structural defect status assessment score F F , determine the type of structural defects in the water supply pipeline based on the structural defect density of the pipe section.

[0012] Furthermore, the calculation method of the structural defect status assessment score F is as follows:

[0013]

[0014] S max =max{P i}

[0015] Where: F——score of pipe section structural defects;

[0016] S max ——The score of the most serious damage in the structural defects of the pipe section;

[0017] S——the average value calculated by the number of defect points in the pipe section structural defects;

[0018] P i ——defect score of the ith defect;

[0019] E i ——defect length influence coefficient of the i-th defect;

[0020] T i ——pressure influence coefficient of the ith defect;

[0021] n is the number of defects in the pipe section.

[0022] Furthermore, the assessment of the structural defect level of the pipe section includes: when F≤1, the defect level is a general defect; when 1<F≤4, the defect level is a major defect; when 4<F≤7, the defect level is a major defect; when F>7, the defect level is an especially major defect.

[0023] Furthermore, the structural defect density D F The calculation method of is as follows,

[0024]

[0025] Where: D F——the density of defects in the affected pipe section;

[0026] L——total length of the assessed pipe section (m);

[0027] L i ——The longitudinal distance length of the ith defect (m).

[0028] Furthermore, when hour,

[0029] Furthermore, when D F ≤0.1, the structural defect type of the pipe section is determined to be a local defect; when 0.1<D G When D G When >0.5, the structural defect type of the pipe section is determined to be an overall defect.

[0030] Furthermore, the defect names include leakage, corrosion, lining layer shedding, deformation, rupture, and wire breakage. Each defect name is divided into three levels and assigned different defect scores.

[0031] Furthermore, each defect name is divided into three levels including,

[0032] The first level of leakage is small leakage, with a leakage volume of less than 8L / min, the second level is medium leakage, with a leakage volume of 8L / min to 40L / min, and the third level is large leakage, with a leakage volume of more than 40L / min.

[0033] The first level of corrosion is mild corrosion - slight peeling of the surface, and concave-convex surfaces on the tube wall; the second level is obvious peeling of the surface, and concave-convex surfaces with an circumferential coverage of no more than 180° on the tube wall; the third level is obvious peeling of the surface, and concave-convex surfaces with an circumferential coverage of more than 180° on the tube wall;

[0034] The first level of lining shedding is that the pipeline anti-corrosion layer is slightly shedding, and the pipeline material is not exposed. The second level is that the pipeline anti-corrosion layer is shedding, the pipeline material is exposed, and the circumferential coverage range is not greater than 30°. The third level is that the pipeline anti-corrosion layer is shedding, the pipeline material is exposed, and the circumferential coverage range is greater than 30°.

[0035] The first level of deformation is deformation not greater than 5% of the pipe diameter, the second level is deformation of 5% to 15% of the pipe diameter, and the third level is deformation greater than 15% of the pipe diameter;

[0036] The first level of rupture is that there are visible fine cracks on the inner wall of the pipeline. The second level is that a clear gap has formed at the rupture, but the shape of the pipeline is not affected and there is no detachment during the rupture. The third level is that the lining has fallen off or water leakage has occurred at the rupture.

[0037] The first level of broken wires is that broken wires occur and the number of broken wires is less than 10, the second level is that the number of broken wires is 10 to 10% of the total number of wire winding loops; the number of broken wires is between 10% and 15% of the total number of wire winding loops and the broken wire areas are not less than 2, the third level is that the number of broken wires is between 10% and 15% of the total number of wire winding loops and the broken wires are concentrated in 1 place; the number of broken wires is not less than 15% of the total number of wire winding loops.

[0038] Furthermore, the three levels of leakage defect scores are 4, 7, and 10;

[0039] The three levels of corrosion defect scores are 2, 4, and 7;

[0040] The three levels of defect scores for liner shedding are 2, 4, and 7 respectively;

[0041] The three levels of deformation defect scores are 1, 4, and 7;

[0042] The three levels of rupture defect scores are 5, 7, and 10;

[0043] The three levels of broken wire defect scores are 5, 7, and 10 respectively.

[0044] Furthermore, the value of the defect length influence coefficient of leakage is assigned as 1.0;

[0045] The value assignment method of the corrosion defect length influence coefficient is: if the defect longitudinal distance is not greater than 1m, it is 1.0; if the defect longitudinal distance is greater than or equal to 1m, it is 1.1;

[0046] The value of the defect length influence coefficient of lining shedding is assigned as 1.0;

[0047] The value assignment method of the deformation defect length influence coefficient is: if the defect longitudinal distance is not greater than 2m, it is 1.0; if the defect longitudinal distance is not less than 2m, it is 1.1;

[0048] The value of the defect length influence coefficient of the rupture is assigned as 2.0;

[0049] The value of the defect length influence coefficient of broken wire is assigned as 1.0.

[0050] In general, the present invention has the following advantages:

[0051] The present invention covers various common structural defects of water supply pipelines, divides the names and levels of structural defects, and clarifies the corresponding pipe section damage condition parameters for different levels of different structural defects. The pipeline structural defect status assessment score and structural defect density are obtained through quantitative analysis and calculation. This method clarifies the classification of water supply pipeline structural defect types and levels, reduces the errors caused by qualitative analysis, is more conducive to the correct assessment of the damage status of water supply pipelines, and provides a reliable basis for subsequent pipeline maintenance and repair. DETAILED DESCRIPTION

[0052] The present invention will be described in further detail below.

[0053] A method for classifying the types and grades of structural defects of a water supply pipeline comprises the following steps:

[0054] Various pipeline structural defects are divided according to names and levels, and pipeline structural defects with multiple levels and names are obtained;

[0055] Based on the obtained pipeline structural defects of multiple levels and multiple names, the corresponding relationship between each pipeline structural defect and the defect score, pressure influence coefficient, and defect length influence coefficient is established;

[0056] The damage condition of the pipeline to be tested is tested to obtain the test result containing the structural defects of the pipeline, and the test result is assigned a value according to the corresponding relationship to calculate the structural defect state assessment score F and the pipe section structural defect density D F ; Determine the structural defect level D of the water supply pipeline according to the structural defect status assessment score F F , determine the type of structural defects in the water supply pipeline based on the structural defect density of the pipe section.

[0057] Specifically, pipeline structural defects refer to defects in which the pipeline structure is damaged and affects strength, rigidity and durability. The method of the present invention classifies the types and grades of structural defects of water supply pipelines through quantitative analysis based on test data, design data, operation and maintenance data and survey data, as follows:

[0058] 1. The present invention classifies the names and levels of structural defects that may occur in pipelines, and different levels of different defects have corresponding defect scores, pressure influence coefficients, and defect length influence coefficients, as shown in Table 1.

[0059] Table 1 Names, grades and scores of structural defects

[0060]

[0061]

[0062] 2. After the pipeline is inspected, according to the inspection results and other relevant information, the damage condition parameters of the pipe section are taken from the above table, and the structural defect status assessment score is calculated according to the following formula:

[0063]

[0064] S max =max{P i} (Formula 3)

[0065] Where: F——score of pipe section structural defects;

[0066] S max ——The score of the most serious damage in the structural defects of the pipe section;

[0067] S——the average value calculated by the number of defect points in the pipe section structural defects;

[0068] P i ——defect score of the ith defect;

[0069] E i ——defect length influence coefficient of the i-th defect;

[0070] T i ——pressure influence coefficient of the ith defect;

[0071] n is the number of defects in the pipe section.

[0072] The pipeline structural defect density should be calculated as follows:

[0073]

[0074] Where: D F ——the density of defects in the affected pipe section;

[0075] L——total length of the assessed pipe section (m);

[0076] L i ——The longitudinal distance length of the ith defect (m). hour,

[0077] 3. The assessment of the structural defect level of the pipe section shall comply with the provisions of Table 2. The assessment of the structural defect type of the pipe section can be determined according to Table 3. After determining the structural defect level and defect type, it can be used as the basis for the achievement report to provide feasible suggestions for pipeline maintenance and repair.

[0078] Table 2 Evaluation table of pipe segment structural defect grades

[0079]

[0080]

[0081] Table 3 Reference table for evaluation of pipe segment structural defect types

[0082] <![CDATA[Defect density D F > <![CDATA[D F ≤0.1]]> <![CDATA[0.1<D F ≤0.5]]> <![CDATA[D F >0.5]]> Structural defect types of pipe sections Local defects Some defects Overall defects

[0083] Advantages of the present invention:

[0084] The present invention proposes a method for dividing the types and levels of structural defects of water supply pipelines, covering various common structural defects of water supply pipelines, dividing the names and levels of structural defects, and clarifying the corresponding pipe section damage condition parameters for different levels of different structural defects. According to the pipeline detection situation, the pipeline structural defect status assessment score and structural defect density can be obtained through quantitative analysis and calculation to determine the pipeline structural defect type and defect level. This method clarifies the division of water supply pipeline structural defect types and levels, reduces the errors caused by qualitative analysis, and is more conducive to the correct assessment of the damage status of water supply pipelines, providing a reliable basis for subsequent pipeline maintenance and repair.

[0085] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A method for classifying the types and grades of structural defects of water supply pipelines, characterized by: The following steps are included: Various pipeline structural defects are divided according to names and levels, and pipeline structural defects with multiple levels and names are obtained; Based on the obtained pipeline structural defects of multiple levels and multiple names, the corresponding relationship between each pipeline structural defect and the defect score, pressure influence coefficient, and defect length influence coefficient is established; The damage condition of the pipeline to be tested is tested to obtain the test result containing the structural defects of the pipeline, and the test result is assigned a value according to the corresponding relationship to calculate the structural defect state assessment score F and the pipe section structural defect density D F ; Determine the structural defect level D of the water supply pipeline according to the structural defect status assessment score F F , determine the type of structural defects in the water supply pipeline based on the structural defect density of the pipe section.

2. A method for classifying types and grades of structural defects of water supply pipelines according to claim 1, characterized in that: The calculation method of structural defect status assessment score F is as follows: S max =max{P i } Where: F——score of pipe section structural defects; S max ——The score of the most serious damage in the structural defects of the pipe section; S——the average value calculated by the number of defect points in the pipe section structural defects; P i ——defect score of the ith defect; E i ——defect length influence coefficient of the i-th defect; T i ——pressure influence coefficient of the i-th defect; n is the number of defects in the pipe section.

3. A method for classifying types and grades of structural defects of water supply pipelines according to claim 2, characterized in that: The assessment of the structural defect level of the pipe section includes: when F≤1, the defect level is a general defect; when 1<F≤4, the defect level is a major defect; when 4<F≤7, the defect level is a major defect; when F>7, the defect level is an especially major defect.

4. A method for classifying types and grades of structural defects of water supply pipelines according to claim 2, characterized in that: Structural defect density of pipe section D F The calculation method of is as follows, Where: D F ——the density of defects in the affected pipe section; L——total length of the assessed pipe section; L i ——The longitudinal distance length of the i-th defect.

5. A method for classifying types and grades of structural defects of water supply pipelines according to claim 4, characterized in that: when hour, 6. A method for classifying types and grades of structural defects of water supply pipelines according to claim 4, characterized in that: When D F ≤0.1, the structural defect type of the pipe section is determined to be a local defect; when 0.1<D G When D G When >0.5, the structural defect type of the pipe section is determined to be an overall defect.

7. A method for classifying types and grades of structural defects of water supply pipelines according to claim 1, characterized in that: The defect names include leakage, corrosion, lining shedding, deformation, rupture, and wire breakage. Each defect name is divided into three levels and assigned different defect scores.

8. A method for classifying types and grades of structural defects of water supply pipelines according to claim 7, characterized in that: Each defect name is divided into three levels including: The first level of leakage is small leakage, with a leakage volume of less than 8L / min, the second level is medium leakage, with a leakage volume of 8L / min to 40L / min, and the third level is large leakage, with a leakage volume of more than 40L / min. The first level of corrosion is mild corrosion - slight peeling of the surface, and concave-convex surfaces on the tube wall; the second level is obvious peeling of the surface, and concave-convex surfaces with an circumferential coverage of no more than 180° on the tube wall; the third level is obvious peeling of the surface, and concave-convex surfaces with an circumferential coverage of more than 180° on the tube wall; The first level of lining shedding is that the pipeline anti-corrosion layer is slightly shedding, and the pipeline material is not exposed. The second level is that the pipeline anti-corrosion layer is shedding, the pipeline material is exposed, and the circumferential coverage range is not greater than 30°. The third level is that the pipeline anti-corrosion layer is shedding, the pipeline material is exposed, and the circumferential coverage range is greater than 30°. The first level of deformation is deformation not greater than 5% of the pipe diameter, the second level is deformation of 5% to 15% of the pipe diameter, and the third level is deformation greater than 15% of the pipe diameter; The first level of rupture is that there are visible fine cracks on the inner wall of the pipeline. The second level is that a clear gap has formed at the rupture, but the shape of the pipeline is not affected and there is no detachment during the rupture. The third level is that the lining has fallen off or water leakage has occurred at the rupture. The first level of broken wires is that broken wires occur and the number of broken wires is less than 10, the second level is that the number of broken wires is 10 to 10% of the total number of wire winding loops; the number of broken wires is between 10% and 15% of the total number of wire winding loops and the broken wire areas are not less than 2, the third level is that the number of broken wires is between 10% and 15% of the total number of wire winding loops and the broken wires are concentrated in 1 place; the number of broken wires is not less than 15% of the total number of wire winding loops.

9. A method for classifying types and grades of structural defects of water supply pipelines according to claim 8, characterized in that: The three levels of leak defect scores are 4, 7, and 10; The three levels of corrosion defect scores are 2, 4, and 7; The three levels of defect scores for liner shedding are 2, 4, and 7 respectively; The three levels of deformation defect scores are 1, 4, and 7; The three levels of rupture defect scores are 5, 7, and 10; The three levels of broken wire defect scores are 5, 7, and 10 respectively.

10. A method for classifying types and grades of structural defects of water supply pipelines according to claim 7, characterized in that: The value of the defect length influence coefficient of leakage is assigned as 1.0; The value assignment method of the corrosion defect length influence coefficient is: if the defect longitudinal distance is not greater than 1m, it is 1.0; if the defect longitudinal distance is greater than or equal to 1m, it is 1.1; The value of the defect length influence coefficient of lining shedding is assigned as 1.0; The value assignment method of the deformation defect length influence coefficient is: if the defect longitudinal distance is not greater than 2m, it is 1.0; if the defect longitudinal distance is not less than 2m, it is 1.1; The value of the defect length influence coefficient of the rupture is assigned as 2.0; The value of the defect length influence coefficient of broken wire is assigned as 1.0.

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