A system and method for detecting residual magnetic field strength of concrete components

Abstract

The invention relates to the technical field of magnetic field strength detection, and in particular to a system and method for detecting residual magnetic field strength of a concrete component; the system and method comprise: a track device, a traction device, an end face detection device for detecting the magnetic field strength of two end faces of a concrete component; an annular detection device for detecting the magnetic field strength of a part of the side surface of the concrete component located in a hollow measuring cylinder; and a main control system for receiving and processing magnetic field strength data of the annular detection device and the end face detection device. The main control system controls the traction device to pull the concrete component into the hollow measuring cylinder in sections, thereby realizing accurate section-by-section movement and pipeline detection of the residual magnetic field strength of the concrete component, greatly improving the efficiency and stability of magnetic detection of the concrete component, filling the industry gap in the field of engineering detection, having low economic cost, being able to detect in a prefabrication site, reducing the transportation time of concrete components, shortening the project construction period, and having high application value.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic field strength detection, and in particular to a system and method for detecting residual magnetic field strength of concrete components. Background Art

[0002] In the fields of astronomical observation, geomagnetic observation, precision measurement, etc., in order to avoid interference of external magnetic fields on the observation results, it is usually necessary to build a non-magnetic or low-magnetic environment. For this reason, non-magnetic or low-magnetic materials are used to make concrete components, and low-magnetic concrete buildings are built by assembling the components. However, the concrete material itself may have a certain degree of magnetism, so it is necessary to accurately detect the magnetic field strength of the concrete raw materials and finished components to ensure that they meet the low-magnetic requirements.

[0003] At present, the magnetic detection of concrete raw materials is mostly carried out by sampling, taking a small amount of samples and placing them in a small magnetic shielding barrel to detect their residual magnetic field strength, but this method has limitations, especially in the magnetic detection of finished concrete components. Due to the large volume and weight of concrete components, it is difficult to carry and move, and the interference of external magnetic fields also affects the detection results. Therefore, it is necessary to design a high-precision magnetic detection device to ensure that the magnetic field strength of concrete components meets the requirements of low magnetic environment.

[0004] The residual magnetism of concrete components must be controlled within tens of nT to ensure that they meet the design standards for low magnetic environments. However, during the production of concrete components, ferromagnetic materials may be mixed in, resulting in the magnetic properties of the components not meeting the standards. Therefore, it is particularly important to conduct residual magnetism testing on precast concrete components.

[0005] To overcome the magnetic field interference generated by the external environment, a huge magnetic shielding room needs to be built, which has the disadvantages of high production cost, inconvenient sample access, uneven magnetic shielding effect, etc. If the detection is directly carried out on the open space on site, the environmental magnetic field interference around the site will have a great impact, and it is extremely difficult to select an area that is not subject to magnetic interference and strong electromagnetic wave interference. The use of handheld proton precession magnetometers, fluxgate magnetometers and other magnetic measuring instruments cannot measure useful data, and the stability and reliability are extremely poor.

[0006] Therefore, for residual magnetism detection of large concrete components, there is an urgent need for a concrete component residual magnetic field strength detection system and method that can be applied to component prefabrication sites, is convenient and fast, and has anti-magnetic interference. Summary of the invention

[0007] In view of the above-mentioned deficiencies in the prior art, the present invention provides a highly efficient, fully streamlined concrete component residual magnetic field strength detection system and method.

[0008] The present invention provides a residual magnetic field strength detection system for a concrete component, comprising:

[0009] A track device, comprising two parallel non-magnetic slide rails, and a slider assembly arranged on the non-magnetic slide rails and capable of sliding back and forth along the non-magnetic slide rails, and a concrete component is placed on the slider assembly;

[0010] A traction device, at least one group, is arranged at one end of the non-magnetic slide rail, and after the traction device is connected to the slider assembly, it drives the concrete component to move on the non-magnetic slide rail;

[0011] There are two end face detection devices, which are respectively arranged at the two ends of the non-magnetic slide rail and are used to detect the magnetic field strength of the two end faces of the concrete component;

[0012] an annular detection device, arranged at the middle position of the non-magnetic slide rail, comprising a hollow measuring cylinder and magnetic detection sensors evenly distributed on the inner wall of the hollow measuring cylinder, the non-magnetic slide rail passes through the interior of the hollow measuring cylinder, the traction device drives the concrete component to enter the hollow measuring cylinder in sections, and the magnetic detection sensor is used to detect the magnetic field strength of the side surface of the part of the concrete component located in the hollow measuring cylinder;

[0013] The main control system is used to receive and process the magnetic field strength data of the annular detection device and the end face detection device, and to control the traction rate of the traction device and the parameter settings of the annular detection device and the end face detection device.

[0014] In this technical solution, the main control system controls the traction device to pull the concrete component into the hollow measuring cylinder in sections, achieving precise segmented movement and assembly-line detection of the residual magnetic field strength of the concrete component, greatly improving the efficiency and stability of component magnetic detection, filling the industry gap in the field of engineering detection, with low economic cost, and can be detected in the prefabrication site, reducing the component transportation time and shortening the project construction period, with high application value.

[0015] In some embodiments of the present application, the hollow measuring cylinder is adapted to the outer contour shape of the concrete component, and the inner wall of the hollow measuring cylinder can fit the outer surface contour of the concrete component, so that the magnetic detection sensor located on the inner wall of the hollow measuring cylinder is at the same distance from the outer surface of the concrete component, ensuring the accuracy of the segmented detection process.

[0016] In some embodiments of the present application, the magnetic detection sensors are distributed in an equidistant array on the inner wall of the hollow measuring cylinder to perform surrounding segmented detection on the surface of the concrete component.

[0017] In some embodiments of the present application, the end face detection device includes a mounting plate and magnetic detection sensors distributed on the mounting plate in an equidistant array. The mounting plate is parallel to the end face of the concrete component and its shape is adapted to the shape of the end face of the concrete component. The magnetic detection sensors can measure the magnetic field strength of each area of ​​the end face.

[0018] In some embodiments of the present application, the main control system includes a human-machine interface for displaying the residual magnetic field strength values ​​of each position of the concrete component measured by the annular detection device and the end face detection device after processing, and for setting the traction rate of the traction device, the annular detection device, and the parameters of the end face detection device.

[0019] In some embodiments of the present application, the non-magnetic slide rail is made of ultra-high molecular polyethylene with a small friction coefficient, which reduces the friction of the concrete component during movement and ensures that the concrete component can slide smoothly.

[0020] In some embodiments of the present application, the magnetic detection sensor is a three-axis fluxgate sensor.

[0021] The method for measuring the residual magnetic field strength of a concrete component using the above-mentioned residual magnetic field strength detection system for a concrete component specifically comprises the following steps:

[0022] Use a hoisting device to hang the concrete component on the non-magnetic slide rail, wherein the concrete component is located at an initial position and is placed stably;

[0023] After the concrete component is placed stably, one of the end face detection devices detects the magnetic field strength of the end face of the concrete component close to it, and transmits the detection data to the main control system in real time;

[0024] Start the traction device, and slowly move the concrete component to the detection area of ​​the hollow measuring cylinder at the preset speed and direction. The traction device stops working, and the magnetic detection sensor starts to detect the magnetic field strength on the side of the concrete component and transmits the real-time detected data to the main control system.

[0025] When the side inspection of the concrete component in the hollow measuring cylinder is completed, the traction device tractions the concrete component again to move it to the next section for inspection, and repeats the above inspection process until the entire side inspection of the concrete component is completed;

[0026] The traction device continues to move the concrete component to the detection area close to the other end surface detection device, and the end surface magnetic detection device detects the magnetic field strength of the remaining end surface of the concrete component and transmits the real-time detected data to the main control system;

[0027] The hoisting device lifts the concrete component that has been inspected off the non-magnetic slide rail, adjusts the next concrete component to be inspected to the initial position, and repeats the above steps to complete the inspection.

[0028] In some embodiments of the present application, the main control system uses a minimum mean square algorithm to filter the detection data of the magnetic detection sensors of the end face detection device and the ring detection device to eliminate the interference of the external magnetic field, specifically:

[0029] (1)

[0030] (2)

[0031] (3)

[0032] in, is the magnetic induction intensity after filtering; w k (t) is the weight coefficient at time t, B k (t) is the measured value of the magnetic field strength input by each magnetic detection sensor at time t, w k (t+1) is the weight coefficient at time t+1, M represents the number of magnetic detection sensors; e(t) is the error between the output signal and the reference value at time t;

[0033] μ is the convergence factor, which is a constant value and is smaller than the inverse of the maximum eigenvalue of the input signal correlation matrix;

[0034] B tar (t) is the actual value of magnetic induction intensity;

[0035] Among them, B k (t) =[B1(t),B2(t),…,B M ( t)],

[0036] W k (t) =[w1(t),w2(t),…,w M ( t)]

[0037] The input form of magnetic field strength is divided into the following two cases:

[0038] (1) M magnetic detection sensors output at the same time, which is M values;

[0039] (2) The outputs of M magnetic detection sensors in the same time period are M sets.

[0040] In some embodiments of the present application, the outputs of M magnetic detection sensors in a certain period of time are used as input, and then:

[0041]

[0042]

[0043]

[0044] ︙

[0045]

[0046]

[0047]

[0048] Where B1(t), B2(t), B3(t)…B M (t) is the magnetic induction intensity measured by M magnetic sensors at time t; , , , …, is the magnetic induction intensity after filtering by the minimum mean square algorithm.

[0049] Based on the above technical solution, the main control system controls the traction device to pull the concrete component into the hollow measuring cylinder in sections, achieving accurate section-by-section movement and assembly-line detection of the residual magnetic field strength of the concrete component, greatly improving the efficiency and stability of component magnetic detection, filling the industry gap in the field of engineering detection, with low economic cost, and can be detected in the prefabrication site, reducing the time for component transportation and shortening the project construction period, with high application value;

[0050] The concrete component can pass through the hollow detection cylinder along the non-magnetic slide rail in an equidistant manner. The equidistant manner cooperates with the equidistant array arrangement of the magnetic detection sensor to ensure that the concrete component can maintain a relatively stable position relationship with the magnetic detection sensor when passing through the hollow detection cylinder, which is convenient for the magnetic detection sensor to perform accurate detection;

[0051] The minimum root mean square algorithm is used to filter the magnetic field strength, which can automatically adapt to the changes in signals and interference. In a dynamically changing magnetic field environment, the adaptive filter can adjust the filter parameters in real time to achieve the best filtering effect. It can effectively shield the external interference magnetic field, reduce the system error interference of the magnetic detection sensor arranged in an equidistant array, and improve the measurement accuracy of the magnetic field strength, which can reach a detection accuracy of 1nT.

[0052] The magnetic detection sensor adopts annular equidistant distributed sensors, which can achieve the purpose of multi-point detection with a small number of sensors. By moving section by section and detecting in different areas, the uneven magnetic field strength on the surface of the component can be quickly measured. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0054] Figure 1 It is a structural schematic diagram of a residual magnetic field strength detection system for concrete components according to an embodiment of the present invention;

[0055] Figure 2 It is a front view of a concrete component and a non-magnetic slide rail according to an embodiment of the present invention;

[0056] Figure 3 It is a schematic structural diagram of the positional relationship among the traction device, the non-magnetic slide rail and the concrete component according to an embodiment of the present invention;

[0057] Figure 4 It is a structural schematic diagram of a slider assembly according to an embodiment of the present invention;

[0058] Figure 5 is a control flow chart of a main control system according to an embodiment of the present invention;

[0059] Figure 6 This is a flow chart of magnetic field strength estimation based on the LMS algorithm according to an embodiment of the present invention.

[0060] In the figure:

[0061] 10. Track device; 11. Non-magnetic slide rail; 12. Slider assembly; 121. Upper support block; 122. Connector; 123. Sliding block; 20. Concrete member; 30. Traction device; 31. Traction rope; 40. End face detection device; 41. Mounting plate; 50. Hollow measuring cylinder; 60. Three-axis fluxgate sensor; 70. Control room. DETAILED DESCRIPTION

[0062] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0063] In the description of the present invention, it should be understood that the terms "center", "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0064] The terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Thus, a feature defined as "first", "second", and "third" may explicitly or implicitly include one or more of the features.

[0065] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0066] As attached Figure 1 As shown, a residual magnetic field strength detection system for a concrete component of this embodiment is provided at a prefabrication site of a concrete component 20, and includes:

[0067] Track device 10, such as Figure 2-Figure 4 As shown, it includes two parallel non-magnetic slide rails 11, and a slider assembly 12 arranged on the non-magnetic slide rails 11 and capable of sliding back and forth along the non-magnetic slide rails 11, and the concrete component 20 is placed on the slider assembly 12; in this embodiment, the non-magnetic slide rail 11 is a "concave"-shaped structure, and is made of ultra-high molecular polyethylene (UHMW-PE) material, which provides a stable and non-magnetic interference mobile platform for the detection of the concrete component 20, and its smooth surface can reduce the friction of the concrete component 20 during the movement, ensuring that it can slide smoothly on the non-magnetic slide rail 11. Since the ultra-high molecular polyethylene material itself is non-magnetic, it will not produce any additional magnetic field interference to the residual magnetic field strength detection of the concrete component 20, thereby ensuring the accuracy of the detection data. The spacing between the two non-magnetic slide rails 11 matches the size and shape of the concrete component 20, has sufficient bearing capacity, and can safely support the movement operation of large concrete components during the detection process.

[0068] like Figure 4As shown, the slider assembly 12 includes, from top to bottom, an upper support block 121 for supporting the concrete member 20, a connecting piece 122 in the middle, and a sliding block 123 for sliding on the non-magnetic slide rail 11. The friction coefficient between the upper support block 121 and the concrete member 20 is large, which prevents the concrete member 20 from sliding off the upper support block during movement. The friction coefficient between the sliding block 123 and the non-magnetic slide rail 11 is small, which reduces the friction force during sliding.

[0069] The traction device 30 has two groups in this embodiment and is arranged at the two ends of the non-magnetic slide rail 11. After the traction device 30 is connected to the slider assembly 12, it drives the concrete component 20 to move at a constant speed on the non-magnetic slide rail 11. In this embodiment, the traction device 30 is a winch. The winch drags the concrete component 20 to slide on the non-magnetic slide rail 11 through the traction rope 31, thereby realizing the movement and positioning of the concrete component, and detecting the residual magnetic field strength of the concrete component in sections. At the same time, it can ensure the stability and accuracy of the concrete component 20 during the movement process, and avoid inaccurate detection data or omission of the detection area due to movement deviation.

[0070] There are two end face detection devices 40, which are respectively arranged at the two ends of the non-magnetic slide rail 11, and are used to detect the magnetic field strength of the two end faces of the concrete component 20; specifically, the end face detection device includes a mounting plate 41, and magnetic detection sensors distributed on the mounting plate 41 in an equidistant array. The magnetic detection sensor of this embodiment is a three-axis fluxgate sensor 60. The mounting plate 41 is parallel to the end face of the concrete component 20, and its shape is adapted to the shape of the end face of the concrete component. In this embodiment, the concrete component 20 is a rectangular parallelepiped component, and its two end faces are both rectangular. The mounting plate 41 is a rectangular structure, and the three-axis fluxgate sensor 60 can measure the magnetic field strength of each area of ​​the end face.

[0071] The annular detection device is arranged at the middle position of the non-magnetic slide rail 11, and includes a hollow measuring cylinder 50 and magnetic detection sensors evenly distributed on the inner wall of the hollow measuring cylinder 50. In this embodiment, the magnetic detection sensor is a three-axis fluxgate sensor 60; the traction device 30 drives the concrete component 20 to enter the hollow measuring cylinder 50 in sections, and the three-axis fluxgate sensor 60 is used to detect the magnetic field strength of the outer peripheral side of the part of the concrete component 20 located in the hollow measuring cylinder 50;

[0072] The hollow measuring tube 50 is adapted to the outer contour of the concrete component 20. In this embodiment, the cross-section of the hollow measuring tube 50 is a rectangle. The length and width of the rectangle are adapted to the length and height of the end face of the concrete component 20, so that the inner wall of the hollow measuring tube 50 can fit the outer surface contour of the concrete component 20. The three-axis fluxgate sensor 60 is distributed in an equidistant array on the inner wall of the hollow measuring tube 50 to perform surrounding segmented detection on the surface of the concrete component. The three-axis fluxgate sensor 60 is at the same distance from the outer surface of the concrete component 20, both of which are 5 cm, to ensure the accuracy of the segmented detection process.

[0073] Sufficient space is left on the bottom surface of the non-magnetic slide rail 11 of this embodiment. The non-magnetic slide rail 11 passes through the inside of the hollow measuring cylinder 50 near the bottom, so that the three-axis fluxgate sensor 60 located on the inner wall below the hollow measuring cylinder 50 can maintain a measuring distance with the bottom surface of the concrete component 20.

[0074] The main control system of this embodiment is arranged in the control room 70, and includes a human-machine interface for displaying the residual magnetic field strength values ​​of each position of the concrete member 20 measured by the annular detection device and the end face detection device 40 after processing, and for setting the traction rate of the traction device 30, and the parameter settings of the annular detection device and the end face detection device 40.

[0075] like Figure 5 As shown, the main control system also includes a position control module to accurately control the contraction length of the traction rope 31 so as to accurately dock with the detection areas of the annular detection device and the end surface detection device 40 to achieve efficient assembly line detection;

[0076] The main control system is used to determine whether the residual magnetic field strength of the concrete component 20 meets the standard requirements. At the same time, it can also monitor and control the entire detection process to optimize the detection performance. In addition, the main control system also has data storage and recording functions, which can store the detection data and analysis results for a long time for subsequent query and tracing, providing a reliable data basis for engineering quality assessment and maintenance.

[0077] In this technical solution, the main control system controls the traction device to pull the concrete component into the hollow measuring cylinder in sections, achieving precise segmented movement and assembly-line detection of the residual magnetic field strength of the concrete component, greatly improving the efficiency and stability of component magnetic detection, filling the industry gap in the field of engineering detection, with low economic cost, and can be detected in the prefabrication site, reducing the component transportation time and shortening the project construction period, with high application value.

[0078] The method for measuring the residual magnetic field strength of a concrete component using the above-mentioned residual magnetic field strength detection system for a concrete component specifically comprises the following steps:

[0079] The concrete component 20 is hoisted on the non-magnetic slide rail using a hoisting device, and the concrete component 20 is located at the initial position, such as Figure 1 As shown, the position is close to the end face detection device 40 on the left, and the distance between the rear end face of the concrete component 20 and the mounting plate 41 of the end face detection device 40 is 5 cm. When hanging, the concrete component 20 is placed stably; start the main control system, calibrate all the three-axis fluxgate sensors 60 on the human-machine interface, and set the parameters of the traction device 30;

[0080] After the concrete component 20 is placed stably, the end face detection device 40 on the left side detects the magnetic field strength of the end face of the concrete component 20 close to it, and transmits the detection data to the main control system in real time. The main control system performs preliminary processing and storage on the data, and performs error correction and interference compensation on the data according to the minimum mean square root algorithm;

[0081] Then the hoist of the traction device 30 is started on the right side, and the concrete component 20 is pulled forward at a preset speed, and is slowly moved to the detection area in the hollow measuring cylinder 50. The hoist stops working, and the three-axis fluxgate sensor 60 in the hollow measuring cylinder 50 starts to detect the magnetic field strength of the four sides of the concrete component 20, and transmits the real-time detected data to the main control system, which continues to perform preliminary processing and storage of the data, and at the same time performs error correction and interference compensation on the data according to the minimum mean square root algorithm;

[0082] When the side inspection of the concrete component 20 in the hollow measuring cylinder 50 is completed, the traction device 30 tractions the concrete component 20 again to move it to the next section for inspection, and the above inspection process is repeated until the entire side inspection of the concrete component is completed;

[0083] The traction device 30 continues to move the concrete component 20 to the detection area close to the end face detection device on the right side, and the distance between the front face and the mounting plate 41 of the end face detection device 40 is 5 cm. The end face detection device 40 performs magnetic field strength detection on the front face of the concrete component 20, and transmits the real-time detected data to the main control system, which continues to perform preliminary processing and storage on the data, and at the same time performs error correction and interference compensation on the data according to the minimum mean square root algorithm;

[0084] The hoisting device lifts the inspected concrete component 20 off the non-magnetic slide rail, adjusts the next concrete component to be inspected to the initial position, and repeats the above steps to complete the inspection.

[0085] Specifically, since the equidistant array three-axis fluxgate sensor 60 is easily disturbed by the external magnetic field when measuring the internal magnetic field of the ring array, which affects the measurement accuracy, the main control system uses the least mean square algorithm (LMS algorithm) for the detection data of the magnetic detection sensors of the end detection device and the ring detection device as a method for adaptive measurement of the array magnetic sensor to reduce magnetic field interference, eliminate the interference of the external magnetic field, and use the magnetic induction intensity as input:

[0086] (1)

[0087] (2)

[0088] (3)

[0089] in, is the magnetic induction intensity after filtering; w k (t) is the weight coefficient at time t, B k (t) is the measured value of the magnetic field strength input by each magnetic detection sensor at time t, w k (t+1) is the weight coefficient at time t+1, M represents the number of magnetic detection sensors; e(t) is the error between the output signal and the reference value at time t;

[0090] μ is the convergence factor, which is a constant value and is smaller than the inverse of the maximum eigenvalue of the input signal correlation matrix;

[0091] B tar (t) is the actual value of magnetic induction intensity;

[0092] like Figure 6 As shown in the figure, it is a flow chart of magnetic field estimation based on the LMS algorithm of formula (1)-(3). Formula (1) filters the input signal, B k (t) is the original signal input to the LMS algorithm, which is obtained by a set of weights w k (t) Perform a weighted summation on the input signal; this process can be viewed as a linear combination of the input signals to produce an estimated signal ; According to the error e(t) calculated by formula (3), update the weight w k (t), formula (2) is the weight update formula, which continuously adjusts the weight to make the output signal as close to the target signal as possible. .

[0093] Among them, B k (t) =[B1(t),B2(t),…,B M ( t)],

[0094] W k(t) =[w1(t),w2(t),…,w M ( t)]

[0095] The input form of magnetic field strength is divided into the following two cases:

[0096] (1) M magnetic detection sensors output at the same time, which is M values;

[0097] (2) The outputs of M magnetic detection sensors in the same time period are M sets.

[0098] Taking the output of M magnetic detection sensors in a certain period of time as input, we have:

[0099]

[0100]

[0101]

[0102] ︙

[0103]

[0104]

[0105]

[0106] Where B1(t), B2(t), B3(t)…B M (t) is the magnetic induction intensity measured by M magnetic sensors at time t; , , ,… is the magnetic induction intensity after filtering by the minimum mean square algorithm.

[0107] The main control system continuously monitors the operating status of each component to ensure the smooth progress of the test. When all the test work is completed, the main control system conducts a comprehensive analysis and interpretation of the residual magnetic field strength data of the entire concrete component and generates a test report, which includes the magnetic field strength data of each measuring point in each part of the component, whether there are abnormal magnetic areas, and an overall assessment of the magnetic state of the component. Finally, the test report is stored and output to provide a basis for subsequent decisions in engineering construction, such as judging whether the component can be put into use and whether further magnetic treatment is required.

[0108] Based on the above technical solution, the main control system controls the traction device to pull the concrete component into the hollow measuring cylinder in sections, achieving accurate section-by-section movement and assembly-line detection of the residual magnetic field strength of the concrete component, greatly improving the efficiency and stability of magnetic detection of concrete components, filling the industry gap in the field of engineering detection, with low economic cost, and can be detected in the prefabrication site, reducing the time for transporting concrete components and shortening the project construction period, with high application value;

[0109] The concrete component can pass through the hollow detection cylinder along the non-magnetic slide rail in an equidistant manner. The equidistant manner cooperates with the equidistant array arrangement of the magnetic detection sensor to ensure that the concrete component can maintain a relatively stable position relationship with the magnetic detection sensor when passing through the hollow detection cylinder, which is convenient for the magnetic detection sensor to perform accurate detection;

[0110] The least mean square algorithm is used to calculate the magnetic field strength, which can automatically adapt to the changes in signals and interference. In a dynamically changing magnetic field environment, the adaptive filter can adjust the filter parameters in real time to achieve the best filtering effect, effectively shield the external interference magnetic field, reduce the system error interference of the magnetic detection sensor arranged in an equidistant array, and improve the measurement accuracy of the magnetic field strength, which can reach a detection accuracy of 1nT.

[0111] The magnetic detection sensor adopts annular equidistant distributed sensors, which can achieve the purpose of multi-point detection with a small number of sensors. By moving section by section and detecting in different areas, the uneven magnetic field strength on the surface of the concrete component can be quickly measured.

[0112] Finally, it should be noted that: the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0113] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should be included in the scope of the technical solution for protection of the present invention.

Claims

1. A residual magnetic field strength detection system for concrete components, characterized in that: include: A track device, comprising two parallel non-magnetic slide rails, and a slider assembly arranged on the non-magnetic slide rails and capable of sliding back and forth along the non-magnetic slide rails, and a concrete component is placed on the slider assembly; A traction device, at least one group, is arranged at one end of the non-magnetic slide rail, and after the traction device is connected to the slider assembly, it drives the concrete component to move on the non-magnetic slide rail; There are two end face detection devices, which are respectively arranged at the two ends of the non-magnetic slide rail and are used to detect the magnetic field strength of the two end faces of the concrete component; an annular detection device, arranged at the middle position of the non-magnetic slide rail, comprising a hollow measuring cylinder and magnetic detection sensors evenly distributed on the inner wall of the hollow measuring cylinder, the non-magnetic slide rail passes through the interior of the hollow measuring cylinder, the traction device drives the concrete component to enter the hollow measuring cylinder in sections, and the magnetic detection sensor is used to detect the magnetic field strength of the side surface of the part of the concrete component located in the hollow measuring cylinder; The main control system is used to receive and process the magnetic field strength data of the annular detection device and the end face detection device, and to control the traction rate of the traction device and the parameter settings of the annular detection device and the end face detection device.

2. The residual magnetic field strength detection system for concrete components according to claim 1, characterized in that: The hollow measuring cylinder is adapted to the outer contour shape of the concrete component, and the inner wall of the hollow measuring cylinder can fit the outer peripheral surface contour of the concrete component, so that the magnetic detection sensor located on the inner wall of the hollow measuring cylinder is at the same distance from the outer surface of the concrete component, ensuring the accuracy of the segmented detection process.

3. The residual magnetic field strength detection system for concrete components according to claim 2 is characterized in that: The magnetic detection sensors are distributed in an equidistant array on the inner wall of the hollow measuring cylinder to perform surrounding segmented detection on the surface of the concrete component.

4. The residual magnetic field strength detection system for concrete components according to claim 1, characterized in that: The end face detection device includes a mounting plate and magnetic detection sensors distributed on the mounting plate in an equidistant array. The mounting plate is parallel to the end face of the concrete component and its shape is adapted to the shape of the end face of the concrete component. The magnetic detection sensors can measure the magnetic field strength of each area of ​​the end face.

5. The residual magnetic field strength detection system for concrete components according to claim 1, characterized in that: The main control system includes a human-machine interface for displaying the residual magnetic field strength values ​​of each position of the concrete component measured by the annular detection device and the end face detection device after processing, and for setting the traction rate of the traction device, the annular detection device, and the parameters of the end face detection device.

6. The residual magnetic field strength detection system for concrete components according to claim 1, characterized in that: The non-magnetic slide rail is made of ultra-high molecular polyethylene.

7. The residual magnetic field strength detection system for concrete components according to claim 1, characterized in that: The magnetic detection sensor is a three-axis fluxgate sensor.

8. A method for detecting residual magnetic field strength by a residual magnetic field strength detection system for concrete components according to any one of claims 1 to 7, comprising the following steps: Use a hoisting device to hang the concrete component on the non-magnetic slide rail, wherein the concrete component is located at an initial position and is placed stably; After the concrete component is placed stably, one of the end face detection devices detects the magnetic field strength of the end face of the concrete component close to it, and transmits the detection data to the main control system in real time; Start the traction device, and slowly move the concrete component to the detection area of ​​the hollow measuring cylinder at the preset speed and direction. The traction device stops working, and the magnetic detection sensor starts to detect the magnetic field strength on the side of the concrete component and transmits the real-time detected data to the main control system. When the side inspection of the concrete component in the hollow measuring cylinder is completed, the traction device tractions the concrete component again to move it to the next section for inspection, and repeats the above inspection process until the entire side inspection of the concrete component is completed; The traction device continues to move the concrete component to the detection area close to the other end surface detection device, and the end surface magnetic detection device detects the magnetic field strength of the remaining end surface of the concrete component and transmits the real-time detected data to the main control system; The hoisting device moves the concrete component that has been inspected away from the non-magnetic slide rail, moves the next concrete component to be inspected to the initial position, and repeats the above steps to complete the inspection.

9. The method for detecting residual magnetic field strength of a concrete component according to claim 8, characterized in that: The main control system uses the least mean square algorithm to filter the detection data of the magnetic detection sensors of the end face detection device and the ring detection device to eliminate the interference of the external magnetic field, specifically: (1) (2) (3) in, is the magnetic induction intensity after filtering; w k (t) is the weight coefficient at time t, B k (t) is the measured value of the magnetic field strength input by each magnetic detection sensor at time t, w k (t+1) is the weight coefficient at time t+1, M represents the number of magnetic detection sensors; e(t) is the error between the output signal and the reference value at time t; μ is the convergence factor, which is a constant value and is smaller than the inverse of the maximum eigenvalue of the input signal correlation matrix; B tar (t) is the actual value of magnetic induction intensity; Among them, B k (t) = [B1 (t), B2 (t),…,B M ( t)], W k ( t) =[w1 ( t),w2 ( t),…,w M ( t)] The input form of magnetic field strength is divided into the following two cases: (1) M magnetic detection sensors output at the same time, which is M values; (2) The outputs of M magnetic detection sensors in the same time period are M sets.

10. The method for detecting residual magnetic field strength of a concrete component according to claim 9, characterized in that: Taking the output of M magnetic detection sensors in a certain period of time as input, we have: ︙ Where B1(t), B2(t), B3(t)…B M (t) is the magnetic induction intensity measured by M magnetic sensors at time t; , , , …, is the magnetic induction intensity after filtering by the minimum mean square algorithm.

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