Nondestructive testing device for corrosion condition of steel bar of concrete pole tower

Abstract

The utility model discloses a nondestructive testing device for the corrosion condition of a steel bar of a concrete tower. The nondestructive testing device comprises a main detection assembly and an auxiliary detection assembly, the main detection assembly comprises a main shell, a main walking unit, a magnetic excitation source, a Hall sensor and a fixing unit. The fixing unit comprises a first bandage, a second bandage and an air bag piece. The air bag part comprises an inflation element and a plurality of air bags arranged on the inner side faces of the first bandage and the second bandage, and the air bags communicate with the inflation element. The auxiliary detection assembly comprises an auxiliary shell, an auxiliary walking unit, a magnetic excitation source and a Hall sensor. The detection device is provided with the main detection assembly and the auxiliary detection assembly, and the main detection assembly and the auxiliary detection assembly cooperate with each other to detect the direction of the main reinforcement in the concrete tower.

Description

Technical Field

[0001] This utility model relates to the technical field of non-destructive testing equipment for reinforcing bars, specifically to a non-destructive testing device for the corrosion of reinforcing bars in concrete towers. Background Technology

[0002] For power auxiliary facilities made of reinforced concrete, such as cement towers, cable ducts, cable covers, and guy wire reels, which have been in operation for a long time, the current methods for inspecting the internal steel reinforcement corrosion are mainly visual inspection or destructive testing. Visual inspection can only detect external cracks in the reinforced concrete structure, while destructive testing can damage the protective layer, causing irreparable damage. Power companies lack effective means to understand the direction, spacing, and corrosion status of the steel reinforcement, and there are no standards for assessing the degree of corrosion. Once the steel reinforcement corrosion worsens and fails to meet mechanical strength requirements, it can lead to accidents such as tower breakage, duct collapse, cover plate load-bearing failure, and guy wire reel breakage, resulting in casualties, equipment failure, and abnormal power grid operation.

[0003] Electromagnetic induction technology is also used to detect steel reinforcement corrosion inside concrete. Electromagnetic induction detection is based on Faraday's law of electromagnetic induction; steel corrosion causes changes in its electromagnetic properties, such as resistivity, magnetic field strength, and permeability. Some existing electromagnetic induction detection devices utilize these properties. By moving a detection probe across the concrete surface, when the probe approaches the corroded steel reinforcement, the induction coil inside the probe generates an induced electromotive force (EMF) due to the change in the steel's electromagnetic properties. The corrosion status is then determined by analyzing the changes in this EMF. However, existing technologies for detecting steel reinforcement corrosion inside concrete suffer from the problem of accurately locating the main reinforcement bars. In actual engineering projects, the main reinforcement bars in concrete towers are not perfectly perpendicular to the stirrups; they often tilt to the left or right, making it difficult to accurately determine their spatial position. Furthermore, concrete tower structures typically have multiple main reinforcement bars. To detect the corrosion and degree of corrosion of a specific main reinforcement bar, its position within the structure must first be determined, and the spacing between the main reinforcement bars must be accurately measured. When facing inclined main reinforcement bars, the detection equipment has difficulty in accurately identifying their actual direction and spatial position, which easily leads to positioning errors. In environments with multiple main reinforcement bars, the detection signals interfere with each other, making it difficult to distinguish the target main reinforcement bars and accurately measure the spacing between them. This results in a lack of reliable basis for subsequent detection of corrosion and its degree, making it difficult to achieve efficient and accurate detection. Utility Model Content

[0004] The purpose of this invention is to solve the above-mentioned technical problems and provide a non-destructive testing device for the corrosion of steel bars in concrete towers.

[0005] To address the shortcomings of the aforementioned technical problems, the present invention adopts the following technical solution: a non-destructive testing device for the corrosion of steel reinforcement in concrete towers, comprising a main testing component and a secondary testing component;

[0006] The main detection component includes a main housing, a main walking unit, a magnetic excitation source, a Hall sensor, and a fixing unit;

[0007] The fixing unit includes a first strap, a second strap, and an airbag component. One end of the first strap and the second strap are fixedly connected to the main housing, and the other end can be connected together by a detachable connector.

[0008] The airbag component includes an inflatable element and a plurality of airbags disposed on the inner sides of the first strap and the second strap, all of which are in communication with the inflatable element.

[0009] The main walking unit includes multiple walking wheels disposed at the bottom of the main housing;

[0010] The secondary detection component includes a secondary housing, a secondary walking unit, a magnetic excitation source, and a Hall sensor;

[0011] The auxiliary walking unit includes multiple ball bearings disposed at the bottom of the auxiliary housing;

[0012] As a further optimization of the non-destructive testing device for steel reinforcement corrosion of concrete towers according to this utility model: the detachable connector is a snap-on connector, a hook-and-loop connector, or a Velcro fastener.

[0013] As a further optimization of the non-destructive testing device for steel reinforcement corrosion of concrete towers of this utility model: each airbag is provided with an air outlet and an air inlet. The air inlet element includes an air pump, an air inlet solenoid valve, and a deflation solenoid valve. The air outlet of the air pump is connected to a main air inlet pipe. The main air inlet pipe is connected to the air inlets of several airbags through a multi-port connector and a pipe. The air inlet solenoid valve is installed on the main air inlet pipe. The air outlets of several airbags are connected to a main deflation pipe through a multi-port connector and a pipe. The deflation solenoid valve is installed on the main deflation pipe.

[0014] As a further optimization of the non-destructive testing device for steel reinforcement corrosion of concrete towers of this utility model: the inflation element also includes a power module, a microcontroller, a key input module, an inflation solenoid valve drive circuit and a deflation solenoid valve drive circuit. The power module provides a stable power supply for the entire circuit, and the microcontroller is used to receive key input signals and control the opening and closing of the solenoid valve according to the signals.

[0015] As a further optimization of the non-destructive testing device for steel reinforcement corrosion of concrete towers according to this utility model: the magnetic excitation source includes a U-shaped magnetic yoke and permanent magnets installed at both ends of the U-shaped magnetic yoke.

[0016] As a further optimization of the non-destructive testing device for steel reinforcement corrosion of concrete towers of this utility model: the U-shaped magnetic yoke is made of pure iron and the permanent magnet is a neodymium iron boron permanent magnet.

[0017] As a further optimization of the non-destructive testing device for steel reinforcement corrosion of concrete towers of this utility model: the magnetic excitation source includes a power supply, a hollow solenoid coil and a current driving circuit.

[0018] As a further optimization of the non-destructive testing device for the corrosion of steel bars in concrete towers according to this utility model: the outer surface of the airbag component is provided with a wear-resistant layer.

[0019] Beneficial effects: The detection device of this utility model has two detection components, a main one and a secondary one, which work together to detect the orientation of the main reinforcement bars in concrete towers. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the main detection component in the detection device of this utility model;

[0021] Figure 2 This is a schematic diagram of the sub-detection component in the detection device of this utility model;

[0022] Figure 3 This is a schematic diagram of the main detection component in the detection device of this utility model being fixed to the concrete rod to be tested by a fixing unit;

[0023] Marked in the image:

[0024] 1. Main detection component;

[0025] 101. Main shell;

[0026] 102. Main traveling unit;

[0027] 103. Fixed unit;

[0028] 1031. First binding strap;

[0029] 1032. Second binding strap;

[0030] 1033. Airbag components;

[0031] 1034. Detachable connectors;

[0032] 1035. Airbag;

[0033] 2. Sub-detection components;

[0034] 201. Secondary shell;

[0035] 202. Secondary walking unit;

[0036] 3. Concrete poles and towers. Detailed Implementation

[0037] To better understand this utility model, the following embodiments further illustrate the content of this utility model, but the content of this utility model is not limited to the following embodiments.

[0038] As shown in the figure: A non-destructive testing device for the corrosion of steel bars in concrete towers includes a main testing component 1 and a secondary testing component 2.

[0039] <Main Detection Component>

[0040] The main detection component 1 includes a main housing 101, a main walking unit 102, a magnetic excitation source, a Hall sensor, and a fixing unit 103.

[0041] The main housing 101 is the basic support structure of the entire main detection assembly, and is usually made of high-strength, corrosion-resistant engineering plastics or aluminum alloys. This material selection ensures the strength of the main housing, enabling it to withstand the weight of the internal components and the stress generated during operation, while also providing good corrosion resistance to adapt to complex outdoor environmental conditions and extend the service life of the device.

[0042] The main traveling unit 102 enables the main detection component 1 to move along the circumference of the concrete pole to be tested. The main traveling unit 102 includes four traveling wheels located at the bottom of the main housing 101; the four traveling wheels travel in the same direction, and during detection, the traveling wheels travel along the circumference of the concrete pole. The traveling wheels adopt a rubber-metal composite rim design, which ensures friction with the concrete surface while avoiding damage to the protective layer.

[0043] There are two types of magnetic excitation sources:

[0044] Form 1: The magnetic excitation source includes a U-shaped magnetic yoke and permanent magnets installed at both ends of the U-shaped yoke. The U-shaped yoke is made of pure iron, and the permanent magnets are neodymium iron boron permanent magnets. A closed magnetic circuit is formed by the U-shaped yoke and the neodymium iron boron permanent magnets, utilizing the constant magnetic field of the permanent magnets to penetrate the concrete protective layer. The pure iron material of the U-shaped yoke effectively constrains the direction of the magnetic field lines, forming a closed loop along the axial direction of the main reinforcing bar, reducing magnetic field diffusion losses. When the reinforcing bar is intact, the magnetic flux is uniformly conducted within the reinforcing bar; if the reinforcing bar is corroded, the reduced permeability in the corroded area (the permeability of iron oxides is much lower than that of steel) leads to increased local magnetic reluctance, causing distortion of the magnetic field lines in that area.

[0045] Form Two: The magnetic excitation source includes a power supply, a hollow solenoid coil, and a current drive circuit. A hollow solenoid, in conjunction with a programmable current drive circuit, generates a dynamic magnetic field through alternating current. Compared to the static field of a permanent magnet, the alternating magnetic field can excite eddy currents in the reinforcing steel, enhancing the electromagnetic response characteristics of the corroded area. The current frequency (typically 10Hz-1kHz) can be adaptively adjusted according to the thickness of the concrete cover: a lower frequency is used for thicker covers to increase penetration depth, while a higher frequency is used for thinner covers to improve resolution.

[0046] Hall effect sensors convert changes in magnetic fields into electrical signals. In this detection device, the Hall effect sensor is positioned at the bottom of the main housing, facing the surface of the concrete pole being measured. When the magnetic field generated by the magnetic excitation source acts on the reinforcing steel bars inside the concrete pole, the corrosion of the steel bars causes changes in their magnetic permeability, thereby altering the distribution of the surrounding magnetic field. The Hall effect sensor can detect these magnetic field changes in real time and accurately, converting them into electrical signals that are then transmitted to the subsequent signal processing module.

[0047] The fixing unit 103 includes a first strap 1031, a second strap 1032 and an airbag component 1033. One end of the first strap 1031 and the second strap 1032 are fixedly connected to the main housing 101, and the other end can be connected together by a detachable connector 1034.

[0048] The first binding strap 1031 and the second binding strap 1032 are made of high-strength and flexible materials, such as nylon fiber or polyester fiber, which can ensure sufficient strength to withstand the weight of the device and the external force during operation, and have good flexibility to fit tightly to the surface of the concrete tower.

[0049] The detachable connector 1034 can be a snap-on connector, a hook-and-loop connector, or a Velcro connector. Snap-on connectors are characterized by a firm connection and easy operation, allowing for connection and disassembly with a simple press; hook-and-loop connectors offer high reliability and stability, suitable for applications requiring frequent disassembly and installation; Velcro connectors offer flexibility and easy adjustment, enabling quick connection and separation of the straps.

[0050] The airbag component 1033 includes an inflation element and several airbags 1035 disposed on the inner sides of the first strap 1031 and the second strap 1032, all of which are connected to the inflation element. The inflation element includes an inflation pump, an inflation solenoid valve, and a deflation solenoid valve. The outlet of the inflation pump is connected to a main inflation pipe, which is connected to the inflation ports of the airbags via a multi-port connector and a pipe. The inflation solenoid valve is located on the main inflation pipe. The outlets of the airbags are connected to a main deflation pipe via a multi-port connector and a pipe. The deflation solenoid valve is located on the main deflation pipe. The airbags are made of high-strength, wear-resistant rubber material, possessing good airtightness and elasticity. Each airbag has an outlet and an inflation port, both of which employ a valve structure with good sealing performance to ensure no leakage occurs during inflation and deflation.

[0051] The inflation component also includes a power module, a microcontroller, a key input module, an inflation solenoid valve drive circuit, and a deflation solenoid valve drive circuit. The power module provides a stable power supply for the entire circuit, and the microcontroller is used to receive key input signals and control the opening and closing of the solenoid valves according to the signals.

[0052] The airbag component 1033 adopts a distributed independent airbag layout. Each airbag 1035 is connected to the main inflation pipe through an independent branch pipe. During inflation, each airbag expands adaptively according to the unevenness of the concrete pole surface, forming "multi-point flexible contact". Through the linkage control of the inflation pump and the solenoid valve, the overall pressure of the airbag can be made uniform.

[0053] When the airbag is inflated to the set pressure (usually 0.05-0.2 MPa), the strap system forms a "rigid-flexible coupling" constraint in the radial direction:

[0054] Rigid constraint: The first strap 1031 and the second strap 1032 form a closed loop through the snap-fit ​​connector 1034 to restrict axial displacement;

[0055] Flexible restraint: The friction between the airbag and the concrete surface can resist the downward sliding due to gravity, while allowing the device to rotate when a tangential force is applied manually.

[0056] This design allows the device to be stably attached to any height on the tower, and also enables 360° circumferential detection through manual rotation.

[0057] When performing the task of detecting steel corrosion on concrete towers, the operator first wraps the first strap 1031 and the second strap 1032 on the main detection component 1 around the surface of the concrete tower 3 to be tested. Using detachable connectors 1034 such as snap-on, hook-and-loop or Velcro, the two straps are connected end to end to form a closed ring structure, thus initially fixing the detection device.

[0058] Subsequently, the air pump in the inflation element is started, and the inflation solenoid valve is opened. Compressed air is rapidly injected into several airbags 1035 distributed on the inner sides of the first binding strap 1031 and the second binding strap 1032 through the main inflation pipe, multi-port connector, and branch pipes. As the airbags 1035 continuously expand, they generate a uniform and stable radial thrust, causing the two binding straps to adhere tightly to the surface of the concrete pole. Through the combined action of friction and pressure, the entire detection device is firmly fixed to the tower.

[0059] At this point, the operator can precisely adjust the working time or air pressure parameters of the air pump according to the testing requirements, dynamically adjusting the inflation volume of the airbag 1035. When the appropriate inflation level is reached, the testing device can overcome its own weight and the swaying during the testing process by relying on the stable pressure provided by the airbag, and firmly maintain itself at the specified height of the concrete pole; it can also flexibly rotate along the circumference of the tower when a moderate external force is applied manually.

[0060] <Sub-detection component>

[0061] The secondary detection component 2 includes a secondary housing 201, a secondary walking unit 202, a magnetic excitation source, and a Hall sensor. The overall structure of the secondary detection component 2 is basically the same as that of the main detection component 1, except that it does not have a fixing unit, and the walking unit is different. The secondary walking unit 202 includes multiple ball bearings located at the bottom of the secondary housing 201.

[0062] The balls are made of high-hardness, low-friction ceramic materials, such as silicon nitride ceramic. This material has excellent wear resistance and self-lubricating properties, maintaining a good surface finish during long-term rolling, reducing wear and energy loss. Each ball is installed in an independent ball socket made of high-strength plastic or metal, with its internal surface finely machined to create a good fit clearance with the ball, ensuring free rolling of the ball within the socket while preventing it from falling out.

[0063] When the auxiliary detection component 2 needs to be moved, the operator can apply a force through an external control device. This force is transmitted to each ball bearing through the auxiliary housing 201. Since the balls can roll freely within the sockets and multiple balls are evenly distributed on the bottom circumference, the auxiliary detection component 2 can move in any direction on the tower surface according to the direction and magnitude of the applied force.

[0064] <Main Reinforcing Bar Direction Inspection>

[0065] First, establish a coordinate system on the concrete outer surface of the cement tower, with x-axis and y-axis. The x-axis is horizontal to the ground, while the y-axis is perpendicular to the horizontal ground.

[0066] Fix the main detection component 1 on the X-axis and move it along the circumferential surface of the cement tower. Observe the corresponding magnetic induction intensity. When the magnetic induction intensity reaches a maximum value and begins to decrease, record the maximum value Pi at this time and plot the corresponding point below.

[0067] The auxiliary detection component 2 is placed above the main detection component 1 and moved along the circumferential surface of the cement tower. The maximum magnetic induction intensity point and its corresponding position are recorded and plotted.

[0068] The line drawn between these two points corresponds to the direction of the center of the main reinforcement bar. Connecting these two points, according to the principle of two points forming a line, the connecting line is the direction of the main reinforcement bar within the cement tower.

[0069] <Main Reinforcement Spacing Detection>

[0070] The spacing between main reinforcement bars refers to the distance between two adjacent main reinforcement bars within a reinforced concrete structure, and it is an important indicator for evaluating the distribution of main reinforcement bars within the concrete. When the spacing between main reinforcement bars is too small, subsequent corrosion may become undetectable. By marking the peak value of the magnetic induction intensity obtained from each test, the position of the exact center of each main reinforcement bar within the reinforced concrete structure can be determined, and the distance between two consecutive peak values ​​is the corresponding main reinforcement bar spacing.

[0071] <Corrosion Detection of Main Reinforcing Bars>

[0072] During the detection process, for the nth measurement point, the peak magnetic flux density and its corresponding planar coordinates are recorded. Simultaneously, the distance the magnetic field excitation source moves directly above the main reinforcement at that point is calculated. Subsequently, the magnetic field excitation source is moved along the direction of the main reinforcement. The above measurement steps are repeated, continuously collecting and storing data. During the movement, the magnetic flux density directly below the magnetic field excitation source and its corresponding position information are recorded; these data constitute the core basis for judging the corrosion of the main reinforcement. After completing all measurements, the corrosion judgment information of each measurement point is connected sequentially. By analyzing the changing characteristics of the connection, it is determined whether the main reinforcement has corroded. This detection method utilizes a Hall sensor installed directly below the magnetic field excitation source to monitor the corrosion of the main reinforcement and the changes in magnetic induction intensity caused by the movement of the excitation source in real time, thereby achieving an accurate judgment of the corrosion or fracture of the main reinforcement. Once a corrosion sign is detected at a point, the corresponding value is recorded. The planar coordinates associated with this value are the projection position of the corroded part on the concrete surface, which determines that the main reinforcement directly below it has corroded.

[0073] The specific embodiments of this utility model have been described above. It should be understood that this utility model is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the substantive content of this utility model.

Claims

1. A non-destructive testing device for the corrosion of reinforcing steel bars in concrete towers, characterized in that: It includes a main detection component (1) and a secondary detection component (2); The main detection component (1) includes a main housing (101), a main walking unit (102), a magnetic excitation source, a Hall sensor, and a fixing unit (103); The fixing unit (103) includes a first strap (1031), a second strap (1032) and an airbag component (1033). One end of the first strap (1031) and the second strap (1032) is fixedly connected to the main housing (101), and the other end can be connected together by a detachable connector (1034). The airbag component (1033) includes an inflation element and a plurality of airbags (1035) disposed on the inner sides of the first strap (1031) and the second strap (1032), and the plurality of airbags (1035) are all in communication with the inflation element. The main walking unit (102) includes a plurality of walking wheels disposed at the bottom of the main housing (101); The secondary detection component (2) includes a secondary housing (201), a secondary walking unit (202), a magnetic excitation source, and a Hall sensor; The secondary walking unit (202) includes a plurality of ball bearings disposed at the bottom of the secondary housing (201).

2. The non-destructive testing device for steel reinforcement corrosion of concrete towers as described in claim 1, characterized in that: The detachable connector (1034) is a snap-on connector, a hook-and-loop connector, or a Velcro fastener.

3. The non-destructive testing device for steel reinforcement corrosion of concrete towers as described in claim 1, characterized in that: Each airbag is equipped with an air outlet and an inflation port. The inflation element includes an inflation pump, an inflation solenoid valve, and a deflation solenoid valve. The air outlet of the inflation pump is connected to a main inflation pipe. The main inflation pipe is connected to the inflation ports of several airbags through a multi-port connector and a pipe. The inflation solenoid valve is located on the main inflation pipe. The air outlets of several airbags are connected to a main deflation pipe through a multi-port connector and a pipe. The deflation solenoid valve is located on the main deflation pipe.

4. The non-destructive testing device for steel reinforcement corrosion of concrete towers as described in claim 3, characterized in that: The inflation element also includes a power module, a microcontroller, a key input module, an inflation solenoid valve drive circuit, and a deflation solenoid valve drive circuit. The power module provides a stable power supply for the entire circuit, and the microcontroller is used to receive key input signals and control the opening and closing of the solenoid valves according to the signals.

5. The non-destructive testing device for steel reinforcement corrosion of concrete towers as described in claim 1, characterized in that: The magnetic excitation source includes a U-shaped magnetic yoke and permanent magnets installed at both ends of the U-shaped magnetic yoke.

6. The non-destructive testing device for steel reinforcement corrosion of concrete towers as described in claim 5, characterized in that: The U-shaped magnetic yoke is made of pure iron, and the permanent magnet is a neodymium iron boron permanent magnet.

7. The non-destructive testing device for steel reinforcement corrosion of concrete towers as described in claim 1, characterized in that: The magnetic excitation source includes a power supply, a hollow solenoid coil, and a current driving circuit.

8. The non-destructive testing device for steel reinforcement corrosion of concrete towers as described in claim 1, characterized in that: The outer surface of the airbag component (1033) is provided with a wear-resistant layer.

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