Method for detecting distribution of steel bars in concrete

Abstract

The invention provides a method for detecting distribution of reinforcing steel bars in concrete, which comprises the following steps of: 1, arranging a plurality of detection points on the surface of the concrete to be detected, and acquiring electromagnetic signal data of the surface of the concrete at each detection point through electromagnetic signal acquisition equipment; 2, calculating electromagnetic field distribution in the concrete at each detection point by using an electromagnetic field inversion algorithm according to the collected electromagnetic signal data; 3, according to the electromagnetic field distribution at each detection point, calculating the position and the trend of the reinforcing steel bar in the concrete by using an electromagnetic induction principle; according to the method, non-destructive detection is adopted, no damage is caused to the concrete structure, the problem that traditional detection can cause damage to the concrete structure is solved, the integrity of the concrete structure is guaranteed, and subsequent repair work and cost increase caused by damage detection are avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of construction engineering, and more specifically, particularly relates to a method for detecting steel bar distribution inside concrete. Background Art

[0002] In the field of modern construction, concrete structure is one of the most widely used building forms. Concrete has become the main material choice for various construction projects due to its good compressive properties and cost-effectiveness. In concrete structures, steel bars play a very important role. They provide tensile strength for concrete structures and enhance the overall stability and bearing capacity of the structure.

[0003] Traditional detection methods mainly rely on manual experience and damage detection. By knocking on the concrete surface, the position of the steel bars can be roughly determined based on the different sounds. However, this method has low accuracy and can only determine the approximate position of the steel bars, but cannot obtain detailed steel bar distribution information. Damage detection requires chiseling the concrete surface and directly observing the distribution of the steel bars. This can provide a more accurate understanding of the steel bar distribution, but it will damage the concrete structure and affect the integrity of the structure. Repairs are also required after detection, increasing project costs and time. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a method for detecting the distribution of steel bars inside concrete, so as to solve the technical problems in the prior art that the traditional detection method mainly relies on manual experience and damage detection, which will cause damage to the concrete structure and affect the integrity of the structure, and also requires repair after detection, increasing the project cost and time.

[0005] The purpose and effect of the method for detecting the distribution of steel bars inside concrete of the present invention are achieved by the following specific technical means:

[0006] A method for detecting steel bar distribution inside concrete comprises the following steps:

[0007] Step 1: Set several detection points on the concrete surface to be detected. These detection points should be evenly distributed in different areas of the concrete surface, and collect electromagnetic signal data of the concrete surface through electromagnetic signal acquisition equipment at each detection point;

[0008] Step 2: Calculate the electromagnetic field distribution inside the concrete at each detection point using an electromagnetic field inversion algorithm based on the collected electromagnetic signal data;

[0009] Step 3: Based on the electromagnetic field distribution at each detection point, use the principle of electromagnetic induction to calculate the position and direction of the steel bars inside the concrete.

[0010] In a preferred embodiment, in step 1, the spacing between the plurality of detection points is 40-60 cm, so as to ensure coverage detection of the steel bar distribution inside the concrete.

[0011] In a preferred embodiment, in step 2, the electromagnetic field inversion algorithm adopts a numerical simulation method based on the finite element method.

[0012] In a preferred embodiment, the electromagnetic field inversion algorithm is:

[0013] B=μ0(H+M)

[0014] Where B represents magnetic induction intensity, μ0 represents vacuum magnetic permeability, H represents magnetic field intensity, and M represents magnetization intensity.

[0015] In a preferred embodiment, in step three, the use of the electromagnetic induction principle to infer the position and direction of the steel bars inside the concrete includes: based on Faraday's law of electromagnetic induction, calculating the induced electromotive force ε at each detection point, the calculation formula is:

[0016] ε=-N(dφ / dt)

[0017] In the formula, ε represents the induced electromotive force, N represents the number of coil turns, and φ represents the magnetic flux.

[0018] In a preferred embodiment, the magnetic flux Φ at each detection point is determined according to the relationship between the induced electromotive force ε and the magnetic induction intensity B, and the calculation formula is:

[0019]

[0020] In this way, the position and direction of the steel bars inside the concrete can be calculated based on the distribution of the magnetic flux φ.

[0021] In a preferred embodiment, the position and direction of the steel bars also include analyzing the distribution law of the magnetic flux Φ between the detection points:

[0022] If Φ shows an obvious peak value between several adjacent detection points, it means that there are steel bars near these detection points;

[0023] By analyzing the location and relative size of these peak points, the general direction of the steel bars can be inferred.

[0024] In a preferred embodiment, the approximate position of the steel bar is determined according to the peak point position of the magnetic flux Φ:

[0025] Match the coordinates of the detection points with the corresponding Φ values, and find the detection point with the largest Φ value. This detection point is the approximate location of the steel bar.

[0026] In a preferred embodiment, the direction of the steel bar is inferred by analyzing the change trend of the Φ values ​​of adjacent detection points:

[0027] If the Φ value changes greatly in a certain direction, it means that the steel bar is in that direction;

[0028] If the Φ value changes little in a certain direction, it means that the steel bar is not in that direction.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. This method adopts non-destructive testing. By setting detection points on the concrete surface and collecting electromagnetic signal data, it will not cause any damage to the concrete structure. It solves the problem that traditional testing will cause damage to the concrete structure, ensures the integrity of the concrete structure, and avoids the subsequent repair work and cost increase caused by damage detection.

[0031] 2. By using the electromagnetic field inversion algorithm and the principle of electromagnetic induction for analysis, the position and direction of the steel bars can be accurately calculated. Compared with the traditional detection method that relies on manual experience, this method based on data analysis can more objectively reflect the actual situation inside the concrete. It helps to understand the internal situation of the concrete structure at all stages of the construction project and discover potential problems in a timely manner, thereby improving the quality of the project and ensuring the safety and stability of the building structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a flow chart of the steps of a method for detecting the distribution of steel bars inside concrete according to the present invention. DETAILED DESCRIPTION

[0033] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with the accompanying drawings and examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0034] Example:

[0035] Please refer to Figure 1 As shown, the present invention provides a method for detecting the distribution of steel bars inside concrete, comprising the following steps:

[0036] Step 1: Set several detection points on the concrete surface to be detected. These detection points should be evenly distributed in different areas of the concrete surface to ensure that the electromagnetic signal data inside the concrete can be fully collected; and collect the electromagnetic signal data of the concrete surface through the electromagnetic signal collection equipment at each detection point;

[0037] Step 2: According to the collected electromagnetic signal data, the collected electromagnetic signal data is analyzed and processed using the electromagnetic field inversion algorithm. Through this algorithm, the electromagnetic field distribution inside the concrete at each detection point can be calculated based on the electromagnetic signal data collected on the surface, providing a reliable basis for the subsequent determination of the steel bar position;

[0038] Step 3: Based on the electromagnetic field distribution at each detection point and the principle of electromagnetic induction, the specific position and direction of the steel bars inside the concrete can be deduced. Metal objects will affect the surrounding electromagnetic fields, causing changes in the electromagnetic field distribution; by analyzing these changes, the position of the steel bars can be determined.

[0039] In step one, the spacing between these detection points should be controlled between 40 and 60 cm to ensure full coverage of the distribution of steel bars inside the concrete and to ensure that the area covered by each detection point can fully overlap, so as to obtain sufficient data to infer the overall distribution of steel bars inside the concrete.

[0040] In step two, the electromagnetic field inversion algorithm adopts a numerical simulation method based on the finite element method; the concrete structure is divided into many small unit grids, and then the corresponding electromagnetic field equations are established for each grid unit. By solving these equations, the electromagnetic field distribution inside the entire concrete structure can be obtained. This numerical simulation method based on the finite element method can make full use of the collected electromagnetic signal data to infer the electromagnetic field distribution inside the concrete; and it can handle complex geometric shapes and boundary conditions, which is very suitable for irregular structures such as concrete. Secondly, it can provide detailed distribution of the electromagnetic field inside the entire structure, providing more comprehensive data support for subsequent steel bar position inference; finally, it has good numerical stability and convergence, which can ensure the reliability of the calculation results.

[0041] The electromagnetic field inversion algorithm is:

[0042] B=μ0(H+M)

[0043] In the formula, B represents magnetic induction intensity, μ0 represents vacuum magnetic permeability, H represents magnetic field intensity, and M represents magnetization intensity;

[0044] In step three, the position and direction of the steel bars inside the concrete are calculated using the principle of electromagnetic induction, including: Based on Faraday's law of electromagnetic induction, the induced electromotive force ε at each detection point is calculated using the following formula:

[0045] ε=-N(dφ / dt)

[0046] Where ε represents the induced electromotive force, N represents the number of coil turns, and φ represents the magnetic flux. When the magnetic flux changes, an induced electromotive force will be generated in the relevant conductor coil. In practical applications, the steel bars inside the concrete act as conductor coils. By systematically scanning and detecting the entire concrete structure and calculating the induced electromotive force values ​​at each detection point, the specific position and direction of the steel bars inside the concrete can be inferred based on these data. Areas with larger induced electromotive force values ​​indicate that there are steel bars there. By analyzing the distribution of induced electromotive force at different detection points, the direction and trend of the steel bars can be further determined.

[0047] According to the relationship between the induced electromotive force ε and the magnetic induction intensity B, the magnetic flux Φ at each detection point is determined, and the calculation formula is:

[0048]

[0049] In this way, the position and direction of the steel bars inside the concrete can be calculated based on the distribution of the magnetic flux φ; areas with larger magnetic flux indicate that there are more steel bars there. By analyzing the distribution of magnetic flux inside the entire concrete structure, the general trend of the steel bars can be outlined.

[0050] By using the electromagnetic field inversion algorithm and the principle of electromagnetic induction for analysis, the specific location and direction of the steel bars inside the concrete can be inferred. Compared with the traditional detection method that relies on manual experience, this method based on data analysis can more objectively reflect the actual situation inside the concrete and avoid the subjective bias that may exist in manual detection. Secondly, this data-driven analysis method can be applied to various stages of construction projects, such as design, construction and maintenance, to help engineers understand the internal conditions of concrete structures in a timely manner and discover potential problems in a timely manner, thereby improving project quality and ensuring the safety and stability of building structures.

[0051] In the specific process of steel bar positioning, analyzing the distribution pattern of magnetic flux Φ between detection points is the key. If Φ shows an obvious peak between several adjacent detection points, it means that there are steel bars near these detection points. Through further analysis of these peak points, the position and direction of the steel bars can be inferred. This analysis method based on magnetic flux distribution can not only locate the position of the steel bars, but also provide important basic information for subsequent structural health assessment and maintenance and reinforcement.

[0052] According to the distribution characteristics of the magnetic flux Φ, the approximate position of the steel bar can be further determined. Specifically, by matching the coordinates of the detection point with the corresponding Φ value, the detection point with the largest Φ value is found. This point is the approximate position of the steel bar. This is because when the detection point is close to the steel bar, due to the effect of electromagnetic induction, the magnetic flux Φ will have an obvious peak value; therefore, by analyzing the distribution of the Φ value, the approximate position of the steel bar can be inferred.

[0053] In addition to using the peak position of the Φ value to determine the approximate position of the steel bar, the direction of the steel bar can also be inferred by analyzing the changing trend of the Φ value of adjacent detection points. Specifically, if the Φ value changes greatly in a certain direction, it means that the steel bar is likely to be located in that direction; conversely, if the Φ value changes less in a certain direction, it indicates that the steel bar is likely not in that direction; this is because when the detection point is close to the steel bar, due to the effect of electromagnetic induction, the Φ value will change significantly, while when it is far away from the steel bar, the change in the Φ value will be relatively small; by analyzing the changing trend of the Φ value in different directions, the direction of the steel bar can be more accurately inferred; this steel bar positioning method based on magnetic flux analysis can not only determine the approximate position of the steel bar, but also provide important information about its direction, which is of great reference value for subsequent structural health assessment and maintenance and reinforcement work.

[0054] This method adopts non-destructive testing; specifically, the test personnel only need to set up several test points on the concrete surface, and by collecting the electromagnetic signal data at these points, they can infer the position and direction of the steel bars without performing any destructive operations on the concrete structure itself. The characteristics of this non-destructive testing solve the problem that traditional testing methods may cause damage to the concrete structure, and effectively protect the integrity of the concrete structure; in contrast, traditional manual testing usually requires destructive operations such as drilling or cutting on the concrete surface, which not only affects the appearance of the concrete structure, but also may lead to a decrease in structural strength, and even cause subsequent repair work and increased costs; the use of non-destructive testing methods based on magnetic flux analysis can avoid these problems and provide safer and more reliable information support for all stages of the construction project; not only can the position and direction of the steel bars be determined, but also a non-destructive testing method is used to effectively protect the integrity of the concrete structure and avoid subsequent repair work and increased costs due to damage detection.

[0055] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A method for detecting the distribution of steel bars inside concrete, characterized in that: The following steps are included: Step 1: Set several detection points on the concrete surface to be detected. These detection points should be evenly distributed in different areas of the concrete surface, and collect electromagnetic signal data of the concrete surface through electromagnetic signal acquisition equipment at each detection point; Step 2: Calculate the electromagnetic field distribution inside the concrete at each detection point using an electromagnetic field inversion algorithm based on the collected electromagnetic signal data; Step 3: Based on the electromagnetic field distribution at each detection point, use the principle of electromagnetic induction to calculate the position and direction of the steel bars inside the concrete.

2. A method for detecting steel bar distribution inside concrete according to claim 1, characterized in that: In step 1, the spacing between the plurality of detection points is 40 to 60 cm, ensuring coverage detection of the steel bar distribution inside the concrete.

3. A method for detecting steel bar distribution inside concrete according to claim 1, characterized in that: In step 2, the electromagnetic field inversion algorithm adopts a numerical simulation method based on the finite element method.

4. A method for detecting steel bar distribution inside concrete according to claim 3, characterized in that: The electromagnetic field inversion algorithm is: B=μ0(H+M) Where B represents magnetic induction intensity, μ0 represents vacuum magnetic permeability, H represents magnetic field intensity, and M represents magnetization intensity.

5. A method for detecting steel bar distribution inside concrete according to claim 1, characterized in that: In step three, the use of the electromagnetic induction principle to infer the position and direction of the steel bars inside the concrete includes: based on Faraday's law of electromagnetic induction, calculating the induced electromotive force ε at each detection point, the calculation formula is: ε=-N(dφ / dt) In the formula, ε represents the induced electromotive force, N represents the number of coil turns, and φ represents the magnetic flux.

6. A method for detecting steel bar distribution inside concrete according to claim 5, characterized in that: According to the relationship between the induced electromotive force ε and the magnetic induction intensity B, the magnetic flux Φ at each detection point is determined, and the calculation formula is: In this way, the position and direction of the steel bars inside the concrete can be calculated based on the distribution of the magnetic flux φ.

7. A method for detecting steel bar distribution inside concrete according to claim 6, characterized in that: The position and direction of the steel bars also include analyzing the distribution of magnetic flux Φ between the detection points: If Φ shows an obvious peak value between several adjacent detection points, it means that there are steel bars near these detection points; By analyzing the location and relative size of these peak points, the general direction of the steel bars can be inferred.

8. A method for detecting steel bar distribution inside concrete according to claim 7, characterized in that: According to the peak point position of the magnetic flux Φ, the approximate position of the steel bar is determined: Match the coordinates of the detection points with the corresponding Φ values, and find the detection point with the largest Φ value. This detection point is the approximate location of the steel bar.

9. A method for detecting steel bar distribution inside concrete according to claim 8, characterized in that: By analyzing the changing trend of Φ values ​​at adjacent detection points, the direction of the steel bars can be inferred: If the Φ value changes greatly in a certain direction, it means that the steel bar is in that direction; If the Φ value changes little in a certain direction, it means that the steel bar is not in that direction.

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