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CN-116500123-B - Detection device and method for fatigue crack of orthotropic plate of steel box girder

CN116500123BCN 116500123 BCN116500123 BCN 116500123BCN-116500123-B

Abstract

The invention discloses a device and a method for detecting fatigue cracks of an orthotropic plate of a steel box girder, comprising the following steps: the steel box girder orthotropic plate fatigue structure is provided with a measuring probe and a probe scanning frame, the measuring probe is mechanically connected with the probe scanning frame through a universal meter rod, and the measuring probe is electrically connected with a magnetic memory detector through a probe wire. The method has the beneficial effect that the crack condition of the orthotropic plate can be accurately detected through the magnetic memory signal.

Inventors

  • WANG CHANGJIANG
  • DONG JIALIN
  • ZHANG YULING
  • ZHANG XIANQING
  • MA QINGANG

Assignees

  • 浙江数智交院科技股份有限公司

Dates

Publication Date
20260508
Application Date
20230407

Claims (10)

  1. 1. The device for detecting the fatigue crack of the orthotropic plate of the steel box girder is characterized by comprising a steel box girder orthotropic plate fatigue structure, wherein the steel box girder orthotropic plate fatigue structure is provided with a three-dimensional measuring probe and a probe scanning frame, the measuring probe is mechanically connected with the probe scanning frame through a universal meter rod, an inward concave arc is arranged at the outer angle part of a sensor position fixer, a first fixing plane and a second fixing plane are respectively arranged at two ends of the sensor position fixer, the inner included angle of the first fixing plane and the second fixing plane is 90-180 degrees, the first fixing plane is provided with a first sensor, the second fixing plane is provided with a second sensor, the first sensor and the second sensor are electrically connected with a magnetic memory detector through probe wires, and the first sensor and the second sensor can rotate by 90 degrees in the planes of the first fixing plane and the second fixing plane so as to switch tangential Z signals or tangential X signals and synchronously measure the tangential Y signals.
  2. 2. The device for detecting fatigue cracks of orthotropic plates of steel box girders according to claim 1, wherein a first fixing plane is provided with a first unidirectional roller, a second fixing plane is provided with a second unidirectional roller, and the first sensor and the second sensor are electrically connected with a magnetic memory detector through probe wires.
  3. 3. A device for detecting fatigue cracks in steel box girder orthotropic plates according to claim 1 or 2, wherein the first sensor and the second sensor are located between the first unidirectional roller and the second unidirectional roller.
  4. 4. The device for detecting fatigue cracks of orthotropic plates of steel box girders according to claim 1 or 2, wherein when the internal angle between the first fixed plane and the second fixed plane is 180 degrees, the direction of the roller bearing is parallel to the connection line of the first sensor and the second sensor, and when the internal angle is 90 degrees, the tangential Z signal of the sensor is perpendicular to or parallel to the running direction X of the roller, and when the tangential Z signal of the sensor is parallel to the tangential X signal.
  5. 5. The device for detecting fatigue cracks of steel box girder orthotropic plates according to claim 1, wherein in the probe scanning frame, a support is connected with an electric X shaft, the electric X shaft is connected with an electric Z shaft, an electric slideway is arranged on the electric Z shaft, the electric slideway is connected with a universal meter rod and a control cabinet, the universal meter rod is connected with a measuring probe, and the control cabinet is connected with a direction controller and a 220V power supply.
  6. 6. The device for detecting fatigue cracks of steel box girder orthotropic plates according to claim 1 or 5, wherein the electric slide is electrically connected with a control cabinet, the control cabinet controls the moving speed of the electric slide, the control cabinet is electrically connected with a direction controller, and the direction controller controls the relative positions of the electric slide in an electric X axis and an electric Z axis.
  7. 7. The device for detecting fatigue cracks of steel box girder orthotropic plates according to claim 1, wherein in the steel box girder orthotropic plate fatigue structure, the U rib and the bridge deck are connected to form a U rib and bridge deck fillet structure, and the U rib and the diaphragm are connected to form a U rib and diaphragm fillet structure and a U rib and diaphragm notch arc edge structure.
  8. 8. A detection device for steel box girder orthotropic plate fatigue cracks according to claim 1 or 7, wherein, The angle of the fillet weld between the U rib and the bridge deck fillet weld structure is 103 degrees, and the angle of the fillet weld between the U rib and the diaphragm fillet weld structure is 90 degrees.
  9. 9. A method for detecting fatigue cracks of orthotropic plates of steel box girders, which adopts the detection device for fatigue cracks of orthotropic plates of steel box girders according to any one of claims 1 to 8, and is characterized by comprising the following steps: S1, preprocessing a detection part; S2, arranging a measuring probe in a detection area; S3, setting the moving speed of the electric slideway based on a measuring path; s4, setting the relative positions of the electric slide ways on the electric X axis and the electric Z axis based on the measurement direction; S5, collecting magnetic field signals, obtaining a data file and a graph file based on the magnetic field signals, and obtaining a detection result based on the data file and the graph file.
  10. 10. The method for detecting fatigue cracks of orthotropic plates of steel box girders according to claim 9, wherein step S2 comprises: The measuring probe is arranged at the fillet weld part of the U-shaped rib and the bridge deck plate in the steel box girder, the internal included angle of the sensor position fixer is adjusted to 103 degrees, and the tangential Z signal direction of the first sensor and the second sensor is perpendicular to the running direction of the roller; Or, arranging the measuring probe at a fillet weld position above the U rib and the diaphragm weld arc notch in the steel box girder, adjusting the internal included angle of the sensor position fixer to 90 degrees, and enabling the tangential Z signal direction of the first sensor and the second sensor to be perpendicular to the running direction of the roller; Or, the measuring probe is arranged at the arc edge of the U rib and the diaphragm plate notch in the steel box girder, the internal included angle of the sensor position fixer is adjusted to be 180 degrees, and the tangential Z signal direction of the first sensor and the second sensor is parallel to the running direction of the roller.

Description

Detection device and method for fatigue crack of orthotropic plate of steel box girder Technical Field The invention relates to the technical field of steel bridge fatigue evaluation, in particular to a device and a method for detecting fatigue cracks of orthotropic plates of steel box girders. Background The steel box girder orthotropic plate structure is a main form of a large-span steel bridge deck because of good overall performance and material saving. However, the local structure is complex, the welding lines are spatially crossed, the load randomness of the bridge deck vehicle is high, the occurrence probability of fatigue cracks is high, and the fatigue evaluation difficulty is increased. And because it is difficult to detect the crack at the initial stage of the crack, the best opportunity for effective measures is often missed. In the prior art, a dynamic strain electrical measurement method is generally adopted to evaluate the fatigue of the steel bridge, strain gauges are stuck on components or steel string strain gauges are arranged to measure the strain history, and then the bridge damage caused by the past passing load is investigated and evaluated. Because the strain gauge is adhered or the placement position of the steel string strain gauge is limited by a complex structure, and meanwhile, the difficulty of researching the historical data of the bridge also leads to errors of the previous fatigue damage evaluation, so that the accuracy of the fatigue evaluation deduced through the measurement result is not high. There is a problem in that the crack condition of the orthotropic plate cannot be precisely detected by the magnetic memory signal. For example, a bridge inspection vehicle disclosed in China patent literature, with publication number CN113022508A, publication number 2015 and publication number 09 and publication number 07, the bridge inspection vehicle comprises a supporting leg mechanism, wherein the supporting leg mechanism comprises a frame, an oil cylinder, a wheel frame and a supporting leg part, the supporting leg part is provided with a first hinge position, a second hinge position and a third hinge position, the first hinge position is hinged with the frame, the second hinge position is hinged with the wheel frame, the third hinge position is hinged with one end of the oil cylinder, the other end of the oil cylinder is hinged with the frame, the third hinge position is positioned between the first hinge position and the second hinge position, and the first hinge position, the second hinge position and the third hinge position are positioned on the same plane, so that the problem of local structural damage caused by overlarge hinge point load transferred to a frame platform of the supporting leg mechanism of the existing bridge inspection vehicle due to unreasonable hinge point design can be solved, but the problem that the condition of an orthotropic plate crack cannot be accurately detected through a magnetic memory signal exists. Disclosure of Invention Aiming at the defect that the crack of the orthotropic plate cannot be accurately detected through the magnetic memory signal in the prior art, the invention provides a device and a method for detecting the fatigue crack of the orthotropic plate of a steel box girder, and the crack condition of the orthotropic plate can be accurately detected through the magnetic memory signal. The technical scheme includes that the device for detecting the fatigue cracks of the orthotropic plates of the steel box girders comprises a steel box girder orthotropic plate fatigue structure, wherein the steel box girder orthotropic plate fatigue structure is provided with a measuring probe and a probe scanning frame, the measuring probe is mechanically connected with the probe scanning frame through a universal meter rod, and the measuring probe is electrically connected with a magnetic memory detector through a probe wire. In the scheme, the steel box girder orthotropic plate fatigue structure is provided with a measuring probe, the measuring probe is used for acquiring magnetic field information of the steel box girder orthotropic plate fatigue structure, the measuring probe is mechanically connected with a probe scanning frame through a universal meter rod, the scanning frame controls the running direction and speed of the measuring probe when the probe scanning frame is used for scanning and measuring the measuring probe in a specified direction at a uniform speed on a measuring site, the measuring probe is electrically connected with a magnetic memory detector through a probe wire, and the magnetic memory detector synchronously records vertical and tangential magnetic memory signals on the surface of a measured object and is used for storing, playing back, analyzing, identifying and outputting the magnetic memory signals. The crack condition of the orthotropic plate can be accurately detected through the magnetic memory signal. Preferably,