Prestressed steel strand pulling effect detection system and method

Abstract

The invention belongs to the technical field of buildings, discloses a system and a method for detecting the strand penetrating effect of prestressed steel strands, and aims to efficiently and accurately position the arrangement of different prestressed steel strands in a corrugated pipe space and improve the construction efficiency and reliability of a prestressed structure. On the basis of the principle that magnetism is generated by electricity, coils are arranged at different positions on each steel strand at intervals, the coils on the steel strands are induced to generate magnetic fields by loading current, and magnetic field signals sent by the coils are received through a plurality of magnetic induction sensors. Through signal processing, data fusion and positioning analysis, the position point of the coil can be accurately calculated, and the coordinate of the position point is output. And finally, the point set is mapped in a 3D space in a 3D modeling mode, lines of different colors are adopted for connecting corresponding position points, and the spatial layout of the different steel strands in the corrugated pipe can be represented. According to the implementation scheme, operation is convenient, the safety of the prestressed steel strand is greatly guaranteed, and the method is suitable for bridge and aqueduct engineering.

Description

Technical Field

[0001] The invention belongs to the field of building technology, and in particular relates to a system and method for detecting the threading effect of a prestressed steel strand. Background Art

[0002] Prestressed structures play a key role in modern architecture and civil engineering, especially in improving the bearing capacity and durability of structures. Prestressed concrete structures can resist greater external loads during the use of the structure by applying tensile stress to the prestressed steel strands. This structural design not only improves the strength and rigidity of the structure, but also reduces the development of cracks in the concrete and extends the service life of the structure.

[0003] In the construction of prestressed structures, corrugated pipes are usually used as the channel for the strands of prestressed steel strands. However, prestressed steel strands may fail during use, which may lead to serious consequences. For example, the tensioning process of the steel strands may cause crossing and entanglement, which in turn affects the stability and safety of the structure. Therefore, timely detection and positioning of the position and status of multiple steel strands inside the corrugated pipe is crucial to ensure the safety and reliability of the prestressed structure.

[0004] At present, the detection of the spatial distribution of multiple steel strands inside the corrugated pipe faces many problems. Generally, it is judged only by the bundle of steel strands. This method can only see the distribution of steel strands at the end of the aqueduct, and cannot understand the specific spatial distribution status of the prestressed steel strands in the corrugated pipe. This method is inefficient and inaccurate. For a hundred-meter-high aqueduct, it is difficult to ensure that the prestressed steel strands pass straight through the corrugated pipe. Some projects do not even detect the spatial layout of steel strands. Therefore, mastering the spatial distribution of steel strands in the corrugated pipe is of great significance to ensure the quality and safety of aqueduct projects, especially for hundred-meter-high aqueducts.

[0005] Therefore, it is necessary to design a system that can accurately detect and display the position of steel strands in the corrugated pipe, which is of great significance for improving the construction quality and efficiency of tall prestressed structures. This system can accurately detect the position of multiple steel strands inside the corrugated pipe and intuitively display the layout of the steel strands through visualization, thereby ensuring the correct arrangement of the steel strands in the structure, which will greatly improve the construction efficiency and reliability of the prestressed structure. Summary of the invention

[0006] The technical problem to be solved by the present invention is to propose a system and method for detecting the threading effect of prestressed steel strands, so as to achieve efficient and accurate positioning of the arrangement of different prestressed steel strands in the space of a corrugated pipe, and improve the construction efficiency and reliability of the prestressed structure.

[0007] The technical solution adopted by the present invention to solve the above technical problems is:

[0008] On the one hand, the present invention provides a prestressed steel strand threading effect detection system, comprising: a plurality of coils arranged on each steel strand, a plurality of magnetic induction sensors arranged outside the prestressed structure, a power supply device and a data processing device;

[0009] The power supply device is used to load current to the steel strands so that the coils on the steel strands are energized and generate a magnetic field;

[0010] The magnetic induction sensor is used to detect the magnetic field data generated by each coil on the steel strand;

[0011] The data processing device is used to establish a unified coordinate system, calculate the position of each coil in the unified coordinate system based on the magnetic field data of each coil detected by the magnetic induction sensor and the position of the magnetic induction sensor in the unified coordinate system, and map the position points of each coil on each steel strand in the 3D model by creating a 3D model of the corrugated tube space. The connection lines of the position points of the coil on each steel strand on the 3D model are visualized to display the spatial layout of each steel strand in the corrugated tube.

[0012] Furthermore, the multiple coils on each steel strand are evenly arranged according to a set interval length, and the coils on different steel strands are arranged at staggered positions, and the sizes of the coils on different steel strands are different.

[0013] Furthermore, the resistance of the coil is smaller than the resistance of the prestressed steel strand, the outer surface of the coil is coated with insulating material, and the outer surface of the coil has good adhesion to the anchor grouting material.

[0014] Furthermore, the magnetic induction sensors are evenly arranged in three rows along the length direction of the bellows outside the prestressed structure, and the signal output end of each magnetic induction sensor is connected to the data processing device.

[0015] Furthermore, the positive electrode of the power supply device is connected to a resistor device, and the negative electrode is connected to a wiring terminal, and the wiring terminal can support all the steel strands in the corrugated tube to be connected through wires at the same time.

[0016] Furthermore, the data processing device includes a processor, a memory and a display screen; the processor is used to pre-process the magnetic field data, perform data fusion and positioning calculations, obtain the position points of each coil, and map the position points of each coil on each steel strand in the 3D model of the corrugated pipe space; the memory is used to store the magnetic field data detected by the magnetic induction sensor, data fusion of the magnetic field intensity data, calculation results of the positioning calculation, and data required for 3D modeling of the corrugated pipe space; the display screen is used to visualize the 3D model of the corrugated pipe space, including a visual display of the connection lines of the position points of the coil on each steel strand on the 3D model, showing the spatial layout of each steel strand in the corrugated pipe.

[0017] On the other hand, the present invention also provides a method for detecting the bundle threading effect of a prestressed steel strand, which is applied to the above-mentioned detection system, and the method comprises the following steps:

[0018] S1. Take one end of the bellows as the reference point and the origin of the coordinate system. Define the coordinate axis using the Cartesian coordinate system according to the direction of the bellows, establish a unified coordinate system, and calibrate the unified coordinate system.

[0019] S2, using a power supply device to load current to the prestressed steel strand in the corrugated tube;

[0020] S3, the magnetic induction sensor detects the magnetic field data generated by each coil on the steel strand;

[0021] S4, the data processing device calculates the position point of each coil in the unified coordinate system according to the magnetic field data of each coil detected by the magnetic induction sensor;

[0022] S5. The data processing device creates a 3D model of the corrugated pipe space, maps the position points of each coil on each steel strand in the 3D model, and displays the spatial layout of each steel strand in the corrugated pipe based on the connection lines of the position points of the coil on each steel strand on the 3D model.

[0023] Furthermore, in step S1, the method of calibrating the unified coordinate system includes: determining the actual installation position of the coil on the steel strand, converting it into a coordinate point in the unified coordinate system, and comparing the coordinate point with the position point of the corresponding coil detected by the magnetic induction sensor, so as to calibrate the unified coordinate system.

[0024] Furthermore, in step S2, the method of using the power supply device to load current to the prestressed steel strand in the corrugated tube includes:

[0025] First loading: Connect the positive pole of the power supply device to a steel strand in one end A of the corrugated tube through a wire, and connect the negative pole of the power supply device to all the steel strands in the other end B of the corrugated tube through a terminal, then turn on the power and start data acquisition;

[0026] Second loading: Connect the positive pole of the power supply device to a steel strand in the other end B of the corrugated tube through a wire, connect the negative pole of the power supply device to all the steel strands in one end A of the corrugated tube through the terminal, then turn on the power and start data acquisition.

[0027] Furthermore, in step S4, the data processing device calculates the position of each coil in the unified coordinate system according to the magnetic field data of each coil detected by the magnetic induction sensor, including:

[0028] First, the magnetic field data of each coil is preprocessed to extract the key features of the magnetic field intensity;

[0029] Then, for each coil, a feature vector containing its position information and the extracted key features of the magnetic field intensity is constructed;

[0030] Next, the weighted average method is used to calculate the fusion feature vector of each coil;

[0031] Finally, according to the fused feature vector of each coil and the positions of different magnetic induction sensors, vector calculation is used to obtain the position point of each coil in the unified coordinate system.

[0032] The beneficial effects of the present invention are:

[0033] (1) The present invention performs detection based on the principle of electromagnetism and magnetic field induction technology, without the need to physically contact or damage the prestressed steel strands, thereby ensuring the integrity and safety of the structure during the detection process. This non-invasive detection method not only avoids potential structural damage, but can also be repeated.

[0034] (2) The present invention can timely discover possible crossing and entanglement problems of the prestressed steel strands by obtaining the precise spatial layout of the prestressed steel strands in the corrugated tube. Such preventive maintenance ensures the safety of the prestressed steel strand tensioning process, improves the long-term stability and durability of the structure, reduces the risk of accidents, and is also conducive to improving construction efficiency.

[0035] (3) Based on the 3D display of the spatial layout of the steel strands in the corrugated pipe, the present invention can guide the tensioning sequence of the prestressed steel strands of the aqueduct, optimize the tensioning plan, and ensure that each steel strand is uniformly stressed according to the design requirements, thereby improving the overall performance and life of the prestressed structure.

[0036] (4) The detection process of the present invention avoids the problems of wasted manpower and low detection efficiency in the traditional manual operation detection of the bundle penetration effect. The detection method is simple and applicable to various prestressed structural projects using plastic corrugated pipes, and has strong applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the application of the detection system in the embodiment of the present invention on the aqueduct;

[0038] Figure 2 Schematic diagram of the arrangement of coils on steel strands in an embodiment of the present invention;

[0039] Figure 3 is a top view of the arrangement of the magnetic induction sensor in an embodiment of the present invention;

[0040] Figure 4 is a front view of the arrangement of the magnetic induction sensor in the embodiment of the present invention;

[0041] Figure 5 is a schematic diagram of magnetic field positioning principle in an embodiment of the present invention;

[0042] Explanation of the markings in the figure: 1 is the prestressed steel strand; 2 is the resistor; 3 is the power supply device; 4 is the conductor; 5 is the terminal block; 6 is the aqueduct; 7 is the coil; 8 is the data processing device; 9 is the magnetic induction sensor; 10 is the plastic bellows. DETAILED DESCRIPTION

[0043] The present invention aims to provide a prestressed steel strand threading effect detection system and method, so as to realize efficient and accurate positioning of the arrangement of different prestressed steel strands in the space of the corrugated pipe, and improve the construction efficiency and reliability of the prestressed structure. The core idea is: based on the principle of electromagnetism, coils are arranged at different intervals on each steel strand in the corrugated pipe, and the coils on the steel strands are induced to generate a magnetic field by loading current, and a plurality of magnetic induction sensors are used to receive the magnetic field signals emitted by the coils. Due to the different positions and coil sizes of the coils on different steel strands, the magnetic field distributions generated are also different, which can be used to distinguish different steel strands; these magnetic field signals are processed by the data processing device through signal processing, data fusion and positioning analysis, and the position points of the coils can be accurately calculated. Finally, through the form of 3D modeling, each position point is mapped in the 3D space, and the points at the corresponding positions are connected by lines of different colors, so as to represent the spatial layout of different steel strands inside the corrugated pipe.

[0044] The scheme of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0045] Example

[0046] Take the implementation of the present invention on a tall prestressed structural member such as an aqueduct as an example, see Figure 1 and Figure 4 In the longitudinal direction of the aqueduct 6, a plastic corrugated tube 10 is used as a bundle passage for the prestressed steel strands 1. First, a coil 7 is arranged on each steel strand 1. Figure 2 As shown. In an optimized embodiment, the surface of the coil 7 is coated with an insulating material, and the surface of the coil 7 has good adhesion with the anchor grouting material such as cement paste, so that when grouting is subsequently poured into the corrugated pipe 10, no gap will be generated, thereby improving the structural stability. In addition, the resistance of the coil 7 should also be smaller than the resistance of the prestressed steel strand 1, so as to prevent the conduction current from flowing in a complex direction after the coil 7 is energized, thereby affecting the magnetic field distribution.

[0047] When arranging the coils 7, multiple coils 7 are arranged at intervals on each steel strand 1, for example, at intervals of 2 meters. In order to facilitate identification of different steel strands 1, the coils 7 arranged on different steel strands 1 have different shapes and sizes, so that the coils 7 on different steel strands 1 have unique position information to distinguish different steel strands 1. In addition, in order to avoid the magnetic fields of the coils 7 on different steel strands 1 from affecting each other and causing inaccurate detection, the coils 7 on different steel strands 1 are arranged staggered, that is, the coils 7 on different steel strands 1 are not aligned in the cross-sectional direction of the corrugated tube 10. After the arrangement is completed, the steel strands 1 are passed through the corrugated tube 10 by a bundle threading machine.

[0048] Next, it is necessary to arrange magnetic induction sensors 9, which can convert the change of magnetic properties of sensitive elements caused by external magnetic fields into electrical signals, thereby detecting magnetic field data. In order to achieve more accurate magnetic field detection, magnetic induction sensors 9 are evenly spaced and arranged in three rows along the length direction of the aqueduct 6, see Figure 3 and Figure 4 The three-row arrangement facilitates the subsequent fusion calculation of magnetic field data and improves the detection accuracy of the magnetic field.

[0049] In order to facilitate the standardized processing of spatial data, a unified coordinate system needs to be established to accurately describe and locate the position of the sensor and coil in space. The unified coordinate system is established by selecting one end of the bellows 10 as the reference point as the origin of the coordinate system, and using the Cartesian coordinate system to define the coordinate axes, where the x-axis, y-axis, and z-axis represent the three main directions of the bellows 10, such as Figure 5 As shown. In this way, the actual installation position of the coil 7 and the actual installation position of the magnetic induction sensor 9 can be converted into the unified coordinate system, and these positions can be recorded for comparison and verification in subsequent data processing and analysis. In addition, in order to ensure the accuracy of the unified coordinate system, the established coordinate system can be calibrated, and the calibration method can be achieved by comparing the coil 7 with the position detected by the magnetic induction sensor 9.

[0050] In terms of data collection and processing, the detection system in this embodiment requires a power supply device 3 and a data processing device 8; wherein, the output voltage of the power supply device 3 is lower than the safety voltage of the human body, thereby ensuring safety during operation; since the resistance of the steel strand 1 is relatively small, in order to avoid damage to the equipment due to excessive loop current during measurement, in this embodiment, a resistor 2 is connected to the positive pole of the power supply device 3, and a terminal 5 is connected to the negative pole of the power supply device 3, and the terminal 5 can support all the steel strands 1 in the corrugated tube 10 to be connected through the wire 4 at the same time.

[0051] The data processing device 8 mainly includes a processor, a memory and a display screen; the processor is the processing core, mainly completing the processing of magnetic field data, data fusion, positioning calculation, etc.; the memory is responsible for storing relevant data; and the display screen assists in visual display. The specific implementation functions of the data processing device 8 will be described in detail later.

[0052] Based on the above detection system, the detection method implemented in this embodiment is as follows:

[0053] 1. Data collection:

[0054] This part is achieved by connecting the conductors 4 on both sides of the steel strand 1 and connecting them to the power supply device 3 to form a closed circuit, and then loading current to induce the coil 7 on the steel strand 1 to generate a magnetic field, so that the magnetic induction sensor 9 can collect the magnetic field data.

[0055] The current loading side needs to be operated twice: during the first loading, the positive pole of the power supply device 3 is connected to a certain steel strand 1 in one end A of the corrugated tube 10 through the wire 4, and the negative pole of the power supply device 3 is connected to all the steel strands 1 in the other end B of the corrugated tube 10 through the terminal 5, and then the power is turned on and data collection is started, and the power is turned off after the collection is completed; during the second loading, the positive pole of the power supply device 3 is connected to a certain steel strand 1 in the other end B of the corrugated tube 10 through the wire 4, and the negative pole of the power supply device 3 is connected to all the steel strands 1 in one end A of the corrugated tube 10 through the terminal 5, and then the power is turned on and data collection is started. After starting data collection twice, the magnetic induction sensor 9 continuously monitors and records the magnetic field signal data generated by the coil 7.

[0056] 2. Data processing:

[0057] This part is the process in which the data processing device 8 processes the magnetic field signal data collected by the magnetic induction sensor 9 to locate the position of each coil 7, which is specifically as follows:

[0058] Data preprocessing: that is, using appropriate filtering algorithms to filter the collected magnetic field signals to remove noise and interference, and to amplify and adjust the signals to improve data quality. And extract key features in the magnetic field strength data, such as peak values, valley values, slope changes, etc. These features reflect the strength and change pattern of the magnetic field signal, and can provide support for subsequent data fusion and positioning calculations.

[0059] Data fusion: Data fusion is mainly the fusion of the collected data of three horizontal rows of magnetic induction sensors, which can reduce the influence of magnetic fields. Specifically, the weighted average method can be used to assign weights to the data of the magnetic induction sensors, and then calculate the weighted average to improve data accuracy, reduce errors, and improve positioning accuracy and reliability. The formula is as follows:

[0060]

[0061] in: is the magnetic field strength after fusion; x i is the magnetic field strength data of the i-th sensor; w i is the weight of the ith sensor.

[0062] Positioning calculation: that is, according to the result of data fusion and the position of magnetic induction sensor 9, the position of coil 7 is located. The details are as follows:

[0063] The magnetic field strength generated by a multi-turn coil is related to the distance. According to the Biot-Savart law, for a point on the axis, the magnetic field strength generated by a single-turn coil is:

[0064]

[0065] Where μ0 is the magnetic permeability of vacuum and I is the current in the coil.

[0066] The magnetic field strength generated by a multi-turn coil is approximately:

[0067]

[0068] Where N is the number of coil turns.

[0069] Assume that the positions of the three magnetic induction sensors are (x1, y1, z1), (x2, y2, z2), and (x3, y3, z3), and the magnetic field strengths they measure are B 1、 B2 and B3. According to the relationship between magnetic field strength and distance, the equation group can be established:

[0070]

[0071] By solving this set of equations, the coordinates (x, y, z) of the center of the coil can be obtained, thereby locating the position of the coil.

[0072] At the same time, since the magnetic field generated by the multi-turn coil is a vector field, the three magnetic induction sensors can measure the vector information (including magnitude and direction) of the magnetic field. Assume that the center position of the multi-turn coil is (x0, y0, z0), at the sensor position (x i ,y i ,z i ) (i=1, 2, 3) magnetic field vector It can be expressed as in It is the magnetic field vector generated by the multi-turn coil at this point under ideal conditions (related to the number of turns, current, position, etc. of the coil). It is the error vector caused by external interference and other factors.

[0073] According to the principle of vector superposition, It can be obtained by superimposing the magnetic field vector generated by each turn of the coil at this point. By comparing the magnetic field vectors measured by the three sensors The direction and magnitude relationship of the coil can be determined by vector operations. At the same time, the position of the coil can be calculated more accurately by operations such as vector decomposition and synthesis, combined with the relationship between magnetic field strength and distance.

[0074] 3. Visual display:

[0075] This part is based on the spatial position of each coil obtained through data processing and 3D modeling. The spatial position points of each coil are mapped to the spatial 3D model of the corrugated pipe, and the point sets of the corresponding positions of each coil on each steel strand are connected with lines to intuitively display the spatial layout of the steel strand.

[0076] Specifically: Use 3D modeling software to create a three-dimensional model to represent the space of the corrugated pipe. And according to the point coordinates of different coils in space, map the position point of each coil to the 3D model. Use lines to connect the center position points of each coil to form the shape of the steel strand. You can choose lines of different colors to distinguish different coils, and judge whether there is cross winding by observing the connection lines of different colors. By adjusting the view of the 3D model, observe the distribution of steel strands at different angles and directions. The distance of the lens can be adjusted to obtain a more detailed or more macro perspective. Finally, output the results: save or export the visualization results of different perspectives of the 3D model to provide guidance for the prestressed steel strand tensioning process.

[0077] Finally, it should be noted that the above embodiments are only preferred implementations and are not intended to limit the present invention. It should be pointed out that for those skilled in the art, several modifications, equivalent replacements, improvements, etc. can be made without departing from the scope of the present invention and the scope of protection of the claims, and all of these should be included in the protection scope of the present invention.

Claims

1. A prestressed steel strand threading effect detection system, characterized in that: include: A plurality of coils arranged on each steel strand, a plurality of magnetic induction sensors arranged outside the prestressed structure, a power supply device and a data processing device; The power supply device is used to load current to the steel strands so that the coils on the steel strands are energized and generate a magnetic field; The magnetic induction sensor is used to detect the magnetic field data generated by each coil on the steel strand; The data processing device is used to establish a unified coordinate system, calculate the position of each coil in the unified coordinate system based on the magnetic field data of each coil detected by the magnetic induction sensor and the position of the magnetic induction sensor in the unified coordinate system, and map the position points of each coil on each steel strand in the 3D model by creating a 3D model of the corrugated tube space. The connection lines of the position points of the coil on each steel strand on the 3D model are visualized to display the spatial layout of each steel strand in the corrugated tube.

2. A prestressed steel strand threading effect detection system according to claim 1, characterized in that: The multiple coils on each steel strand are evenly arranged according to a set interval length, and the coils on different steel strands are arranged at staggered positions, and the sizes of the coils on different steel strands are different.

3. A prestressed steel strand threading effect detection system according to claim 1, characterized in that: The resistance of the coil is less than that of the prestressed steel strand, the outer surface of the coil is coated with insulating material, and the outer surface of the coil has good adhesion with the anchor grouting material.

4. A prestressed steel strand threading effect detection system according to claim 1, characterized in that: The magnetic induction sensors are evenly arranged in three rows outside the prestressed structure along the length direction of the corrugated pipe, and the signal output end of each magnetic induction sensor is connected to the data processing device.

5. A prestressed steel strand threading effect detection system according to claim 1, characterized in that: The positive pole of the power supply device is connected to a resistor device, and the negative pole is connected to a wiring terminal, and the wiring terminal can support all the steel strands in the corrugated tube to be connected through wires at the same time.

6. A prestressed steel strand threading effect detection system according to claim 1, characterized in that: The data processing device includes a processor, a memory and a display screen; The processor is used to perform data fusion and positioning calculation after preprocessing the magnetic field data, obtain the position points of each coil, and map the position points of each coil on each steel strand in the 3D model of the corrugated pipe space; The memory is used to store magnetic field data detected by the magnetic induction sensor, data fusion of magnetic field strength data, calculation results of positioning calculation, and data required for 3D modeling of the bellows space; The display screen is used to visualize the 3D model of the corrugated pipe space, including visualizing the connection lines based on the position points of the coils on each steel strand on the 3D model, and displaying the spatial layout of each steel strand in the corrugated pipe.

7. A method for detecting the bundle effect of a prestressed steel strand, applied to the prestressed steel strand bundle effect detection system according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: S1. Take one end of the bellows as the reference point and the origin of the coordinate system. Define the coordinate axis using the Cartesian coordinate system according to the direction of the bellows, establish a unified coordinate system, and calibrate the unified coordinate system. S2, using a power supply device to load current to the prestressed steel strand in the corrugated tube; S3, the magnetic induction sensor detects the magnetic field data generated by each coil on the steel strand; S4, the data processing device calculates the position point of each coil in the unified coordinate system according to the magnetic field data of each coil detected by the magnetic induction sensor; S5. The data processing device creates a 3D model of the corrugated pipe space, maps the position points of each coil on each steel strand in the 3D model, and displays the spatial layout of each steel strand in the corrugated pipe based on the connection lines of the position points of the coil on each steel strand on the 3D model.

8. A method for detecting the bundle threading effect of prestressed steel strands according to claim 7, characterized in that: In step S1, the method of calibrating the unified coordinate system includes: determining the actual installation position of the coil on the steel strand, converting it into a coordinate point in the unified coordinate system, and comparing the coordinate point with the position point of the corresponding coil detected by the magnetic induction sensor to calibrate the unified coordinate system.

9. A method for detecting the bundle threading effect of prestressed steel strands according to claim 7, characterized in that: In step S2, the method of using the power supply device to load current to the prestressed steel strand in the corrugated tube includes: First loading: Connect the positive pole of the power supply device to a steel strand in one end A of the corrugated tube through a wire, and connect the negative pole of the power supply device to all the steel strands in the other end B of the corrugated tube through a terminal, then turn on the power and start data acquisition; Second loading: Connect the positive pole of the power supply device to a steel strand in the other end B of the corrugated tube through a wire, connect the negative pole of the power supply device to all the steel strands in one end A of the corrugated tube through the terminal, then turn on the power and start data acquisition.

10. A method for detecting the bundle threading effect of prestressed steel strands according to claim 7, characterized in that: In step S4, the data processing device calculates the position of each coil in the unified coordinate system according to the magnetic field data of each coil detected by the magnetic induction sensor, including: First, the magnetic field data of each coil is preprocessed to extract the key features of the magnetic field intensity; Then, for each coil, a feature vector containing its position information and the extracted key features of the magnetic field intensity is constructed; Next, the weighted average method is used to calculate the fusion feature vector of each coil; Finally, according to the fused feature vector of each coil and the positions of different magnetic induction sensors, vector calculation is used to obtain the position point of each coil in the unified coordinate system.

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