Intelligent detection device for damage of prestressed tendon of concrete T-beam bridge

Abstract

The invention discloses an intelligent detection device for concrete T-beam bridge prestressed tendon damage. The intelligent detection device comprises a carrying platform and an excitation and signal acquisition device arranged on the carrying platform. The excitation and signal acquisition device is used for sensing magnetic field changes and acquiring prestressed tendon damage characteristic parameter information of a target section in the concrete T beam; the carrying platform is hung on a horseshoe-shaped structure on the lower portion of the T beam in a surrounding mode and can carry the excitation and signal collecting device to move along the beam body, and movement detection of a target section of the beam body is achieved. According to the invention, the main section of the beam body can be continuously tracked and detected, the leak detection risk is reduced, and the damage detection efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of bridge detection, and particularly to an intelligent detection device for prestressed tendon damage of a concrete T-beam bridge. Background Art

[0002] The prestressed concrete T-beam bridge is a common structural form in bridge engineering. Its main feature is that the cross-section of the beam is in the shape of a T. By applying pre-compressive stress in the concrete beam through prestressed tendons (usually steel strands), the bending resistance and spanning ability of the beam are improved. However, over time and under the influence of the external environment, the prestressed tendons may be damaged, such as corrosion caused by chloride ion erosion, wire breakage of the steel strands caused by fatigue, etc. These damages will seriously affect the safety and service life of the bridge.

[0003] For the existing detection devices or equipment for prestressed tendon damage of concrete T-beam bridges, except for manual assistance, there is no effective means to implement detection. The operation is not flexible enough, resulting in low efficiency and a high risk of undetected defects. Moreover, for the prestressed tendons covered by the concrete protective layer, their detection ability is greatly limited.

[0004] Therefore, to solve the above problems, an intelligent detection device for prestressed tendon damage of a concrete T-beam bridge is needed, which can continuously track and detect the main sections of the beam body, reduce the risk of undetected defects, improve the detection ability for prestressed tendon damage covered by the concrete protective layer, and greatly improve the damage detection efficiency. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to overcome the defects in the prior art and provide an intelligent detection device for prestressed tendon damage of a concrete T-beam bridge, which can continuously track and detect the main sections of the beam body, reduce the risk of undetected defects, and improve the damage detection efficiency.

[0006] The intelligent detection device for prestressed tendon damage of the concrete T-beam bridge of the present invention includes a carrier platform and an excitation and signal acquisition device arranged on the carrier platform;

[0007] The excitation and signal acquisition device is used to sense the magnetic field change and obtain the information of the corrosion characteristic parameters of the prestressed tendons in the target section inside the concrete T-beam;

[0008] The carrier platform is hung on the protruding horseshoe-shaped structure at the lower part of the T-beam in a surrounding manner and moves along the beam body with the excitation and signal acquisition device to realize the mobile detection of the target section of the beam body.

[0009] Further, the carrier platform includes a platform base and a plurality of robotic arms arranged along the moving direction of the carrier platform; the plurality of robotic arms include a first robotic arm group arranged at one end of the platform base and a second robotic arm group symmetric to the first robotic arm group and arranged at the other end of the platform base.

[0010] Further, the robotic arm includes a robotic arm driving wheel, a suspension transport robotic arm, a hydraulic connecting rod, an upper transport robotic arm, and a transport robotic base;

[0011] One end of the robotic arm is arranged on the platform base through the transport robotic base, and a robotic arm driving wheel is arranged at the other end of the robotic arm;

[0012] The end of the suspension transport robotic arm is provided with a motor to drive the robotic arm driving wheel, and a hydraulic cylinder is arranged in the transport robotic base and connected to a DC motor to control the upper transport robotic arm, and then the opening and closing of the suspension transport robotic arm is controlled through the hydraulic connecting rod.

[0013] Further, a DC motor and a driven wheel are arranged on the platform base; the DC motor is used to drive the driven wheel, so that after all the robotic arms are retracted, the transport platform moves by using the driven wheel.

[0014] Further, the excitation and signal acquisition device includes an armature, and a permanent magnet and a Hall sensor array both arranged on the armature; there are two permanent magnets, and the Hall sensor array is arranged in the middle of the two permanent magnets.

[0015] Further, the excitation and signal acquisition device moves on the transport platform through a moving module;

[0016] The moving module includes a moving track, a crawler belt, a servo motor, and a driving wheel; the servo motor drives the crawler belt through the driving wheel to control the excitation and signal acquisition device to move along the moving track.

[0017] Further, the crawler belt includes a first crawler belt arranged along the moving direction of the transport platform and a second crawler belt arranged perpendicular to the moving direction of the transport platform.

[0018] Further, when the transport platform encounters a diaphragm during movement, it crosses the diaphragm according to the following method:

[0019] Set the moving detection distance of the transport platform according to the following formula: l i = l - l 0 ; where l i is the moving detection distance of the transport platform, l is the longitudinal length of the lower horseshoe structure of the T-beam, and l 0 is the length of the transport platform;

[0020] An infrared ranging device is arranged on the suspension transport robotic arm of each pair of robotic arms, and the minimum distance x from the outer edge of the suspension transport robotic arm to the diaphragm is set mWithin the mobile detection range of the carrier platform, infrared ranging is used to detect in turn whether the distance from the suspension transport robot arm of each pair of robot arms to the diaphragm reaches the preset minimum distance x m ;

[0021] If the first pair of robotic arms reaches the preset minimum distance x m , then the first pair of mechanical arms at the front end is opened, and the carrying platform continues to move forward along the beam. If the first pair of mechanical arms passes through the diaphragm, the second pair of mechanical arms reaches the preset minimum distance x from the diaphragm. m , then close the first pair of robotic arms and hang them on the horseshoe-shaped structure on the other side of the diaphragm, and then open the second pair of robotic arms; and so on, until all the robotic arms pass through the diaphragm.

[0022] The beneficial effects of the present invention are as follows: an intelligent detection device for damage to prestressed tendons of a concrete T-beam bridge disclosed by the present invention utilizes a carrier platform to carry an excitation and signal acquisition device, a plurality of pairs of robotic arms are installed on the carrier platform, the robotic arms can be adjusted by opening and closing so that the wheel groups at the ends of the robotic arms are hung in an embracing manner on the horseshoe-shaped widened structure at the bottom of the T-beam, the excitation and signal acquisition device is carried by the wheel groups at the ends of the robotic arms and the driving device to move along the beam body, thereby realizing continuous tracking detection of the beam body. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0024] Figure 1 It is an overall schematic diagram of the intelligent detection device of the present invention;

[0025] Figure 2 is a cross-sectional view of a mobile module of the present invention;

[0026] Figure 3 It is a schematic diagram of the excitation and signal acquisition device of the present invention;

[0027] Figure 4 It is a schematic elevation view of the detection device of the present invention attached to a T-beam;

[0028] Figure 5 It is a cross-sectional schematic diagram of the detection device of the present invention attached to a T-beam;

[0029] Figure 6 It is a schematic elevation view of the first pair of mechanical arms of the detection device of the present invention deployed through the diaphragm;

[0030] Figure 7 It is a cross-sectional schematic diagram of the detection device of the present invention when the first pair of mechanical arms are deployed through the diaphragm;

[0031] Figure 8 This is a schematic diagram of the detection device of the present invention walking on a bridge deck;

[0032] Among them, 1 - the driving wheel of the robotic arm; 2 - the suspended transportation robotic arm; 3 - the hydraulic connecting rod; 4 - the upper arm of the transportation machinery; 5 - the base of the transportation machinery; 6 - the DC motor; 7 - the driven wheel; 8 - the excitation and signal acquisition device; 9 - the crawler; 10 - the moving track; 11 - the driving wheel; 12 - the steel guard plate; 13 - the servo motor; 14 - the permanent magnet; 15 - the armature; 16 - the TMR Hall sensor. Specific implementation mode

[0033] The following further describes the present invention with reference to the accompanying drawings of the specification, as shown in the figures:

[0034] This embodiment discloses an intelligent detection device for prestressed tendon damage of a concrete T-beam bridge, including a carrier platform and an excitation and signal acquisition device 8 arranged on the carrier platform;

[0035] The excitation and signal acquisition device 8 is used to sense the magnetic field change and obtain the information of the corrosion characteristic parameters of the prestressed tendons in the target section inside the concrete T-beam;

[0036] The carrier platform is hung on the protruding horseshoe-shaped structure at the lower part of the T-beam in a surrounding manner and moves along the beam body with the excitation and signal acquisition device 8 to realize the mobile detection of the target section of the beam body. Among them, the T-beam is the abbreviation of the T-shaped cross-section beam.

[0037] The detection device of the present invention fully considers the structural characteristics of the concrete T-beam, moves along the horseshoe-shaped structure at the lower edge of the T-beam by hanging, ensures the stability and accuracy of the device during the detection process, and can intelligently cross the transverse diaphragms between the beams to realize the detection of the corrosion and fatigue damage of the prestressed tendons inside the beam body. Compared with other non-destructive testing technologies, it has the characteristics of strong applicability, high detection accuracy, more automation, intelligence, and informatization, and has high detection reliability.

[0038] The present invention is based on the MFL principle, and the prestressed tendons inside the concrete T-beam bridge body are excited by magnetization (using the permanent magnet as the magnetic source) to make the prestressed tendons reach the magnetic saturation state, and the damage degree of the prestressed steel bars is judged by collecting and analyzing the generated magnetic flux leakage signals. Among them, the magnetic flux leakage detection (MFL, Magnetic Flux Leakage) method is a non-destructive testing method, which has the characteristics of non-contact sensing, insensitivity to non-ferrous metal materials, and strong detection ability for external and internal defects.

[0039] In this embodiment, as Figure 4 、 5 shown, the carrier platform includes a platform base and a plurality of robotic arms arranged along the moving direction of the carrier platform; the plurality of robotic arms include a first robotic arm group arranged at one end of the platform base and a second robotic arm group symmetric to the first robotic arm group and arranged at the other end of the platform base.

[0040] The symmetrically arranged first and second robotic arm groups can be flexibly adjusted to adapt to T-beams of different sizes, improving the versatility and adaptability of the detection device, and enabling the carrier platform to automatically hang and move along the horseshoe-shaped structure at the lower edge of the T-beam, realizing continuous and precise detection of prestressed tendons, improving the detection efficiency, and moreover, without the need for additional support equipment, reducing manual intervention, and enhancing the intelligence and automation level of detection.

[0041] In this embodiment, as Figure 1 shown, the robotic arm includes a robotic arm driving wheel 1, a suspension and transportation robotic arm 2, a hydraulic connecting rod 3, an upper transportation robotic arm 4, and a transportation robotic base 5; one end of the robotic arm is arranged on the platform base through the transportation robotic base 5, and a robotic arm driving wheel 1 is arranged at the other end of the robotic arm; a motor is arranged at the end of the suspension and transportation robotic arm 2 to drive the robotic arm driving wheel 1, a hydraulic cylinder is arranged in the transportation robotic base 5 and is connected to a DC motor 6 to control the upper transportation robotic arm 4, and then the opening and closing of the suspension and transportation robotic arm 2 is controlled through the hydraulic connecting rod 3.

[0042] The motor drive of the robotic arm driving wheel 1 ensures that the carrier platform can move smoothly, improving the detection stability and accuracy. The linkage control of the hydraulic cylinder and the DC motor 6 enables the robotic arm to be flexibly adjusted, realizing automatic grasping and adaptive adjustment of the T-beam, and enhancing the adaptability to T-beams of different sizes; the opening and closing control of the suspension and transportation robotic arm 2 improves the operation convenience of the device, enabling it to be quickly deployed and withdrawn, thus improving the detection efficiency. In addition, the above structural design of the robotic arm ensures that the carrier platform can always closely adhere to the T-beam during the movement process, reducing the jitter and deviation during the detection process, ensuring the accuracy and reliability of signal acquisition, and thus improving the intelligence and automation level of the damage detection of prestressed tendons.

[0043] In this embodiment, a DC motor 6 and a driven wheel 7 are arranged on the platform base; the DC motor 6 is used to drive the driven wheel 7, so that after all the robotic arms are retracted, the carrier platform moves by using the driven wheel 7. As Figure 8 shown, the robotic arms contract in the reverse direction, and the whole device is inverted to form a trolley shape, and the driven wheel 7 is driven by the DC motor 6 to become the driving wheel, enabling the detection device to move on a plane, which is convenient for transportation and used for detecting the corrosion damage of the prestressed tendons on the top and bottom plates of the concrete box girder in the bridge.

[0044] By driving the driven wheel 7 with the DC motor 6, the carrier platform can move independently after all the robotic arms are retracted, improving the mobility and convenience of the detection device and avoiding relying on external traction equipment. The setting of the driven wheel 7 ensures that the carrier platform travels smoothly on the bridge structure, reducing vibration and deviation, and improving the detection stability and accuracy. In addition, the above setting enables the platform to quickly withdraw after the detection is completed, improving the detection efficiency.

[0045] In this embodiment, as Figure 3 shown, the excitation and signal acquisition device 8 includes an armature 15, a permanent magnet 14 and a Hall sensor array that are all arranged on the armature 15; there are two permanent magnets 14, and the Hall sensor array is arranged in the middle of the two permanent magnets. Among them, the Hall sensor uses a three-dimensional TMR Hall sensor 16. The permanent magnet excites the internal prestressed tendons of the beam to generate magnetic signals, which are received by the Hall sensor. By receiving data such as magnetic leakage signals through the Hall sensor, the severity and location of damage such as corrosion of the internal prestressed tendons of the T-beam can be quickly obtained to evaluate the health status of the T-beam.

[0046] The double permanent magnet structure enhances the stability and uniformity of the magnetic field, making the magnetic induction intensity more stable during the detection process, and improving the accuracy and reliability of signal acquisition. The Hall sensor is arranged between the two permanent magnets, which can accurately sense the magnetic field change, and perform high-sensitivity detection on the damage, corrosion and fracture of the prestressed tendons, improving the resolution and sensitivity of the detection device. By setting the armature, the magnetic circuit can be optimized, the magnetic flux density can be increased, and thus the induction ability of the target section inside the T-beam can be enhanced. By setting the sensor array, more useful information can be extracted from the leakage magnetic field, so that a more accurate quantitative evaluation of the damage of the prestressed tendons can be performed. The excitation and signal acquisition device 8 combines with the automatic movement function of the carrier platform to realize non-contact, automated and efficient detection of the bridge prestressed tendons, providing accurate, intelligent and efficient technical support for bridge structural health monitoring.

[0047] In this embodiment, the excitation and signal acquisition device 8 moves on the carrier platform through a moving module; as Figure 2 shown, the moving module includes a moving track 10, a crawler 9, a servo motor 13 and a driving wheel 11; the servo motor 13 drives the crawler 9 through the driving wheel 11 to control the movement of the excitation and signal acquisition device 8 along the moving track 10.

[0048] Utilizing the crawler 9 drive combined with the servo motor 13 and the driving wheel 11 enables the excitation and signal acquisition device 8 to move axially along the moving track 10 smoothly and precisely, ensuring the coverage range and continuity of the detection area and avoiding missed detections. Moreover, the crawler 9 structure can provide better grip, enabling stable operation in complex bridge environments, reducing sliding or deviation, and thus improving the stability and adaptability of the device. In addition, the precise control of the servo motor 13 enables the device to perform detailed precise positioning, realizing efficient and automated detection operations, and greatly improving the work efficiency.

[0049] In this embodiment, the crawler 9 includes a first crawler arranged along the moving direction of the carrier platform and a second crawler arranged perpendicular to the moving direction of the carrier platform.

[0050] Through the two-way setting of the crawler 9, that is, the first crawler and the second crawler, the stability and flexibility of the excitation and signal acquisition device 8 in the longitudinal and transverse directions are ensured. The second crawler can adjust the transverse position of the excitation and signal acquisition device 8. While reducing the weight of the device, it can meet the detection requirements of wide-size T-beam structures. And it can easily cope with the complex environment in the bridge structure, improving the detection range and detection efficiency of the equipment.

[0051] In this embodiment, as Figure 6 , 7 shown, when the carrier platform encounters a diaphragm during movement, it crosses the diaphragm according to the following method:

[0052] Based on infrared ranging to determine the relative position between the carrier platform and the T-beam diaphragm during the mobile detection process. When the carrier platform is close to the diaphragm, the first pair of robotic arms at the front end is opened and it continues to move forward until the first pair of robotic arms at the front end crosses the diaphragm. At this time, the first pair of robotic arms is retracted and again carried on the horseshoe-shaped widened structure at the lower edge of the T-beam; by analogy, the second pair, the third pair to the last pair of robotic arms cross the diaphragm in sequence, realizing the overall crossing of the carrier platform over the diaphragm, forming a highly automated full-beam inspection plan, thereby realizing the detection of the target section of the beam body.

[0053] Specifically, set the mobile detection distance of the carrier platform according to the following formula: l i = l - l 0 ; where l i is the mobile detection distance of the carrier platform, l is the longitudinal length of the horseshoe-shaped structure at the lower part of the T-beam, and l 0 is the length of the carrier platform;

[0054] An infrared ranging device is set on the suspension transport robotic arm of each pair of robotic arms. Set the minimum distance x m from the outer edge of the suspension transport robotic arm to the diaphragm. Within the mobile detection distance range of the carrier platform, through infrared ranging, sequentially detect whether the distance from the suspension transport robotic arm of each pair of robotic arms to the diaphragm reaches the preset minimum distance x m ; where the minimum distance x m can be set according to the actual working conditions.

[0055] If the first pair of robotic arms reaches the preset minimum distance x m , it is confirmed that the carrier platform is close to the diaphragm, which is used as the condition for opening the first pair of robotic arms. Open the first pair of robotic arms at the front end, and the carrier platform continues to move forward along the beam. If the first pair of robotic arms passes through the diaphragm and the second pair of robotic arms is at a distance from the diaphragm reaching the preset minimum distance x m, then close the first pair of robotic arms and hang them on the horseshoe-shaped structure on the other side of the diaphragm, and then open the second pair of robotic arms; and so on, until all the robotic arms pass through the diaphragm.

[0056] After the first pair of robotic arms reaches the preset minimum distance, the second pair of robotic arms reaches the minimum distance immediately, the first pair of robotic arms retracts to the horseshoe structure, and the detection device continues to move forward, and so on. When the last pair of robotic arms passes through the diaphragm, the purpose of the automatic crossing diaphragm function is achieved.

[0057] Through infrared ranging technology, the relative position of the carrier platform and the T-beam diaphragm can be accurately determined, ensuring that the platform can automatically identify and adjust when it approaches the diaphragm; by gradually opening the robotic arm, the carrier platform can smoothly cross the diaphragm to avoid stagnation or damage caused by structural obstacles. This automated crossing method not only improves the flexibility and adaptability of the carrier platform, but also enhances the equipment's ability to pass in complex bridge environments, greatly improving detection efficiency and continuity. By accurately controlling the crossing timing of each robotic arm, the stability and safety of the carrier platform during movement are ensured, thereby realizing efficient and intelligent bridge prestressed tendon damage detection.

[0058] In addition, the entire detection device is transported and used for prestressed tendon damage detection on the top and bottom plates of concrete box girders in bridges. Figure 8 As shown, the robot arm contracts in the reverse direction, and the entire device is inverted to form a mobile trolley, and the DC motor 6 drives the driven wheel to become the driving wheel, so that the detection device can move on the top and bottom plate surfaces of the box girder and implement damage detection for the prestressed tendons in the plate.

[0059] Finally, it should be noted that 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, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. An intelligent detection device for prestressed tendon damage in a concrete T-beam bridge, characterized in that: It includes a carrier platform and an excitation and signal acquisition device arranged on the carrier platform; The excitation and signal acquisition device is used to sense the change of the magnetic field and obtain the characteristic parameter information of the corrosion of the prestressed tendons in the target section inside the concrete T-beam; The carrying platform is hung on the protruding horseshoe structure at the bottom of the T-beam in an embracing manner, and carries the excitation and signal acquisition devices to move along the beam body to achieve mobile detection of the target section of the beam body.

2. The intelligent detection device for prestressed tendon damage in concrete T-beam bridge according to claim 1 is characterized in that: The carrying platform includes a platform base and a plurality of mechanical arms arranged along the moving direction of the carrying platform; the plurality of mechanical arms include a first mechanical arm group arranged at one end of the platform base and a second mechanical arm group symmetrical to the first mechanical arm group and arranged at the other end of the platform base.

3. The intelligent detection device for prestressed tendon damage in concrete T-beam bridge according to claim 2 is characterized in that: The mechanical arm comprises a mechanical arm driving wheel, a suspension transport mechanical arm, a hydraulic connecting rod, a transport mechanical upper arm and a transport mechanical base; One end of the mechanical arm is arranged on the platform base through the transport mechanical base, and the other end of the mechanical arm is provided with a mechanical arm driving wheel; A motor-driven mechanical arm driving wheel is arranged at the end of the suspension transport mechanical arm, and a hydraulic cylinder connected to a DC motor is arranged in the transport mechanical base to control the upper arm of the transport mechanical arm, and then the opening and closing of the suspension transport mechanical arm is controlled by a hydraulic connecting rod.

4. The intelligent detection device for prestressed tendon damage in concrete T-beam bridge according to claim 2 is characterized in that: A DC motor and a driven wheel are arranged on the platform base; the DC motor is used to drive the driven wheel, so that after all the mechanical arms are retracted, the carrying platform moves using the driven wheel.

5. The intelligent detection device for prestressed tendon damage in concrete T-beam bridge according to claim 1 is characterized in that: The excitation and signal acquisition device comprises an armature, a permanent magnet and a Hall sensor array both arranged on the armature; there are two permanent magnets, and the Hall sensor array is arranged between the two permanent magnets.

6. The intelligent detection device for prestressed tendon damage in concrete T-beam bridge according to claim 1 is characterized in that: The excitation and signal acquisition device is moved on the carrier platform through a moving module; The mobile module includes a mobile track, a crawler belt, a servo motor and a transmission wheel; the servo motor drives the crawler belt through the transmission wheel to control the excitation and signal acquisition device to move along the mobile track.

7. The intelligent detection device for prestressed tendon damage in concrete T-beam bridge according to claim 6 is characterized in that: The crawler belt comprises a first crawler belt arranged along the moving direction of the carrying platform and a second crawler belt arranged perpendicular to the moving direction of the carrying platform.

8. The intelligent detection device for prestressed tendon damage in concrete T-beam bridge according to claim 3 is characterized by: If the carrying platform encounters a diaphragm during movement, it can cross the diaphragm in the following way: Set the mobile detection distance of the carrier platform according to the following formula: i =l-l0; where l i is the moving detection distance of the carrying platform, l is the length of the horseshoe structure at the bottom of the T beam along the bridge direction, and l0 is the length of the carrying platform; An infrared distance measuring device is installed on the suspension transport mechanical arm of each pair of mechanical arms to set the minimum distance x from the outer edge of the suspension transport mechanical arm to the cross partition. m Within the mobile detection range of the carrier platform, infrared ranging is used to detect in turn whether the distance from the suspension transport robot arm of each pair of robot arms to the diaphragm reaches the preset minimum distance x m ; If the first pair of robotic arms reaches the preset minimum distance x m , then the first pair of mechanical arms at the front end is opened, and the carrying platform continues to move forward along the beam. If the first pair of mechanical arms passes through the diaphragm, the second pair of mechanical arms reaches the preset minimum distance x from the diaphragm. m , then close the first pair of robotic arms and hang them on the horseshoe-shaped structure on the other side of the diaphragm, and then open the second pair of robotic arms; and so on, until all the robotic arms pass through the diaphragm.

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