A scanning device for rapid detection of steel bridge decks and u-rib

Abstract

The application relates to the technical field of steel structure detection and nondestructive testing, in particular to a scanning device for rapidly detecting a steel bridge deck and U ribs. The scanning device comprises a walking mechanism, a scanner and a step counting and marking mechanism. The scanner comprises a crossbar and a plurality of detection probes, the detection probes are distributed at intervals along the length direction of the crossbar, and the crossbar is arranged on the walking mechanism; the step counting and marking mechanism is arranged on the walking mechanism, the step counting and marking mechanism is connected with the scanner, and is used for marking on the steel bridge deck when the detection probes detect defects existing in the steel bridge deck or the U ribs. The scanning device for rapidly detecting the steel bridge deck and the U ribs is provided, so that the problems of complex operation and low efficiency in the detection process of the steel bridge deck and the U ribs in the related art are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steel structure detection and nondestructive testing, and in particular relates to a scanning device for rapidly detecting a steel bridge deck and U ribs. BACKGROUND

[0002] With the acceleration of current urban construction and the stabilization of steel prices, steel bridge structure design of large and medium span is increasingly applied and built. For the top plate of a steel bridge, orthotropic steel bridge deck top plates are generally used. This is because they have outstanding advantages such as light structure weight, strong spanning capacity, high overall efficiency, and good seismic performance. However, due to uncontrollable industry in the design and manufacturing process, and the effect of heavy vehicles on the bridge deck, the orthotropic steel bridge deck top plate and U ribs are prone to fatigue damage and even cracking. For example, due to the actual traffic flow far exceeding the designed traffic flow, combined with the serious overloading of vehicles, the bridge deck top plate of Junshan Yangtze River Bridge repeatedly deformed under the rolling of heavy vehicle wheels, and many top plate cracks were found in 2016, which were evaluated as a third-level disease by professional institutions.

[0003] In related technologies, we often need to periodically detect and long-term monitor the fatigue cracking of an orthotropic steel bridge deck in service. The current detection methods include the following: acoustic wave detection, fracture line monitoring, and video image detection. Acoustic wave detection includes conventional ultrasonic waves and guided waves, which mainly use the reflection of cracks on ultrasonic waves to detect cracks. The fracture line is attached to the target position, and once the steel plate cracks, the fracture line is also pulled off, and the cracking of the steel plate can be known through the change of the resistance. Video images use image recognition methods to directly identify cracks from images.

[0004] However, the above methods are too complex to operate and the efficiency needs to be improved. SUMMARY

[0005] Embodiments of the present application provide a scanning device for rapidly detecting a steel bridge deck and U ribs to solve the problem of complex operation and low efficiency in the detection process of the steel bridge deck and U ribs in related technologies.

[0006] To achieve the above purpose, the present application provides a scanning device for rapidly detecting a steel bridge deck and U ribs, comprising:

[0007] a walking mechanism;

[0008] a scanner, the scanner comprising a crossbar and a plurality of detection probes, the detection probes being distributed along the length direction of the crossbar, and the crossbar being arranged on the walking mechanism;

[0009] A step counting and marking mechanism is arranged on the walking mechanism, and is connected with the scanner and used for marking on the steel bridge deck when the detection probe detects that the steel bridge deck or the U rib has defects.

[0010] In some embodiments, the two horizontal rods are arranged horizontally, and one of the two horizontal rods is movably arranged on the other horizontal rod.

[0011] In some embodiments, a plurality of through holes are arranged along the length of one of the two horizontal rods, and at least one through hole is arranged along the length of the other horizontal rod, and the two horizontal rods are fixed by pins through the through holes.

[0012] In some embodiments, a through hole perpendicular to the horizontal plane is arranged on the horizontal rod.

[0013] The detection probe comprises a detection rod, a height fixing wheel and a magnetic memory probe, the outer diameter of the detection rod is smaller than the through hole, and the detection rod is arranged in the through hole, and the height fixing wheel and the magnetic memory probe are arranged on the detection rod.

[0014] In some embodiments, a receiving space is arranged in the middle of the horizontal rod, the through hole penetrates the receiving space, and a limiting block is arranged on the detection rod and located in the receiving space.

[0015] In some embodiments, the walking mechanism comprises:

[0016] A horizontal beam is arranged with a port for connecting the scanner.

[0017] Two inclined beams are connected with the horizontal beam and form a triangular structure.

[0018] Two load wheels are connected at the two ends of the horizontal beam.

[0019] A stabilizing wheel is connected at the connection of the two inclined beams, and the axial directions of the load wheels and the stabilizing wheel are the same.

[0020] In some embodiments, an encoder is arranged on the stabilizing wheel and connected with the scanner.

[0021] In some embodiments, the step counting and marking mechanism comprises:

[0022] A marking device is arranged with a nozzle facing the steel bridge deck.

[0023] A host computer is connected with the scanner and the marking device, and is used for receiving the detection signal of the detection probe and controlling the marking device to make marks when the detection probe detects that the steel bridge deck or the U rib has defects.

[0024] In some embodiments, the host also pre-stores coordinates of each detection probe; the host is further configured to acquire, according to the detection signal and the pre-stored coordinates, a detection probe that detects a defect on the steel bridge deck or U rib, and adjust the orientation of the nozzle to spray the steel bridge deck below the detection probe.

[0025] In some embodiments, the host is further provided with a positioning system.

[0026] The technical scheme provided by the application has the beneficial effects that the scanner is placed on the walking mechanism, and can be towed by the work vehicle or pushed by manpower to scan the steel bridge deck and U rib on the surface of the steel bridge. Meanwhile, the multiple magnetic memory detection probes cover a larger detection area, and the operation is simple, the efficiency is improved, and the step counting and marking mechanism can mark the abnormal area when detecting the abnormal area of the bridge deck magnetic signal, facilitating the next step of processing.

[0027] The embodiment of the application provides a scanning device for quickly detecting a steel bridge deck and U rib. In the process of stress concentration and fatigue damage of the bridge deck top plate and the U rib, the bridge deck top plate and the U rib will produce spontaneous magnetization phenomenon, which is externally manifested as a small magnetic field. The spontaneous magnetization phenomenon of the ferromagnetic metal under the condition of stress concentration and fatigue damage is called "magnetic mechanical effect". The application adopts the metal magnetic memory principle to detect the stress concentration and fatigue damage of the bridge deck top plate. The scanner is placed on the walking mechanism, which saves the manpower to carry the heavy and inconvenient device, and is beneficial to the transportation and storage of the instrument. The scanning device can be hung behind the work vehicle, towed by the vehicle, and advanced with the vehicle to improve the detection efficiency. In special cases, the system can also use the manpower to push the scanning device. The multiple detection probes improve the scanning area and scanning efficiency, and the step counting and marking mechanism marks the abnormal area of the magnetic signal when the scanner scans the abnormal area, which is convenient for subsequent processing and saves time and effort. Therefore, the problems of complex operation and low efficiency in the related art of detecting the steel bridge deck and U rib can be solved. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical schemes in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creating laborious work.

[0029] Figure 1 The structure diagram of the scanning device for quickly detecting the steel bridge deck and U rib provided by the embodiment of the application;

[0030] Figure 2A linear array schematic diagram of a scanner of a scanning device for quickly detecting a steel bridge deck and U ribs is provided in the embodiments of the present application.

[0031] Figure 3 A front view of a detection probe of a scanning device for quickly detecting a steel bridge deck and U ribs is provided in the embodiments of the present application.

[0032] Figure 4 A side view of a detection probe of a scanning device for quickly detecting a steel bridge deck and U ribs is provided in the embodiments of the present application.

[0033] In the figure: 1, scanner; 10, detection probe; 100, magnetic memory probe; 101, limiting block; 102, height fixing wheel; 103, detection rod; 11, cross rod; 110, containing space; 12, through hole; 13, through hole; 2, walking mechanism; 20, cross beam; 21, inclined beam; 22, load wheel; 23, stabilizing wheel; 24, encoder; 3, step counting and marking mechanism; 30, main machine; 31, marking device. DETAILED DESCRIPTION

[0034] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in connection with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0035] The embodiments of the present application provide a scanning device for quickly detecting a steel bridge deck and U ribs, which can solve the problems of complex operation and low efficiency in the related art during the detection process of the steel bridge deck and U ribs.

[0036] Referring to Figures 1 to 4 As shown in the figure, the present application provides a scanning device for quickly detecting a steel bridge deck and U ribs, which comprises a walking mechanism 2, a scanner 1 and a step counting and marking mechanism 3. The scanner 1 comprises a cross rod 11 and a plurality of detection probes 10, the detection probes 10 are distributed along the length direction of the cross rod 11, and the cross rod 11 is arranged on the walking mechanism 2; the step counting and marking mechanism 3 is arranged on the walking mechanism 2, the step counting and marking mechanism 3 is connected with the scanner 1, and is used for marking on the steel bridge deck when the detection probes 10 detect defects in the steel bridge deck or U ribs.

[0037] During stress concentration and fatigue damage in the bridge deck top plate and U-ribs, they spontaneously magnetize, manifesting as a tiny magnetic field. This phenomenon of spontaneous magnetization in ferromagnetic metals under stress concentration and fatigue damage is known as the "magnetomechanical effect." This physical phenomenon is also used to assess stress concentration and fatigue damage in magnetic metals, a technique known as "metal magnetic memory" testing.

[0038] The solution of the present invention adopts the principle of metal magnetic memory to detect stress concentration and fatigue damage of the bridge deck top plate. The embodiment of the present application provides a scanning device for rapid detection of steel bridge decks and U-ribs. Since the scanner 1 is placed on the walking mechanism 2, the cumbersomeness and inconvenience of manual carrying are eliminated, which is conducive to the transportation and storage of the instrument. In addition, the scanning device can be hung behind the working vehicle, towed by the vehicle, and follow the vehicle to improve the detection efficiency. Under special circumstances, the scanning device can also be pushed by manpower to perform scanning and detection. Multiple detection probes 10 increase the scanning area and scanning efficiency. The step counting marking mechanism 3 will make a mark when the scanner 1 scans an abnormal magnetic signal area, which is convenient for subsequent processing. There is no need for manual marking or re-analysis of the image, saving time and effort. Therefore, the problem of complex operation and low efficiency in the detection process of steel bridge decks and U-ribs in the related art can be solved.

[0039] Specifically, the scanner 1 can be mounted on the traveling mechanism 2 via a crossbar 11, or a slot compatible with the scanner 1 can be provided on the traveling mechanism 2 and the scanner 1 can be placed in the slot. The detection probe 10 can be hung on the crossbar 11 or adhered to the crossbar 11. Preferably, the pedometer marking mechanism 3 is electrically connected to the scanner 1. Preferably, a warning light is fixed at the outermost ends of the scanner 1 to remind bridge users in other lanes to avoid and prevent traffic accidents.

[0040] In some preferred embodiments, there are two cross bars 11 , which are arranged horizontally, and one of the cross bars 11 is movably assembled on the other cross bar 11 .

[0041] Specifically, in actual detection, lane widths often vary, typically between 3.75m and 4m. Two crossbars 11 can be freely combined based on the width of the lane to be scanned, adapting to narrow or wide lanes. Alternatively, three or more crossbars 11 can be provided to similarly achieve coverage of lanes of varying widths.

[0042] In some preferred embodiments, see Figure 2 As shown, one of the cross bars 11 has a plurality of through holes 13 distributed along its length, and the other cross bar 11 has at least one through hole 13 distributed along its length. The two cross bars 11 are fixed by pins through the through holes 13 .

[0043] Specifically, the combination length of the two horizontal rods 11 is completed by the relative positions of the different through holes 13. Figure 2 As shown, one of the horizontal rods 11 provided with multiple through holes 13 can be temporarily referred to as a first horizontal rod, and the other horizontal rod 11 provided with at least one through hole 13 can be temporarily referred to as a second horizontal rod. When the through hole 13 on the second horizontal rod is threaded relative to the first through hole 13 on the first horizontal rod, the combined length of the two horizontal rods 11 is the longest; when the through hole 13 on the second horizontal rod is threaded relative to the last through hole 13 on the first horizontal rod, the combined length of the two horizontal rods 11 is the shortest. It should be noted that, in order to ensure the stability of the combination of the two horizontal rods 11, several through holes 13 can be additionally provided thereon. In addition, the through holes 13 can be circular, square or of other shapes.

[0044] Of course, other connection methods can also be adopted, such as connection and fixation through sliding rails and clamping grooves. A pulley can be provided on one of the horizontal rods 11, a matching sliding groove can be provided on the other horizontal rod 11, and a clamping groove can be provided at a suitable node to facilitate the fixation of the two horizontal rods 11.

[0045] In some preferred embodiments, referring to Figures 2 to 4 As shown, the horizontal rod 11 is provided with a through hole 12 perpendicular to the horizontal plane; in addition, the detection probe 10 comprises a detection rod 103, a height fixing wheel 102 and a magnetic memory probe 100, the outer diameter of the detection rod 103 is smaller than the through hole 12, and the detection rod 103 is threaded through the through hole 12, and the height fixing wheel 102 and the magnetic memory probe 100 are both arranged on the detection rod 103.

[0046] Specifically, the through hole 12 is arranged on the horizontal rod 11 at a fixed interval, for example, a center distance of 50 mm, the inner diameter of the through hole 12 matches the outer diameter of the detection rod 103, and is slightly larger than the outer diameter of the detection rod 103, so that the detection rod 103 can move up and down in the through hole 12. The height fixing wheel 102 is arranged at one end of the detection rod 103 close to the ground and protrudes from the detection rod 103 by a certain distance, so that the distance between the detection rod 103 and the ground can be kept constant during detection. It should be noted that the cross-sectional shape of the through hole 12 and the detection rod 103 in the horizontal plane is consistent, only the size is slightly different; the cross-sectional shape can be circular, rectangular or polygonal.

[0047] In some preferred embodiments, referring to Figure 2 As shown, a receiving space 110 is arranged in the middle of the horizontal rod 11, and the through hole 12 penetrates the receiving space 110; and a limiting block 101 is arranged on the detection rod 103, and the limiting block 101 is located in the receiving space 110.

[0048] Specifically, the receiving space 110 can be rectangular, on one hand, the distribution of the detection probe 10 on the crossbar 11 can be clearly seen, on the other hand, the receiving space 110 can accommodate the limiting block 101 on the detection rod 103, limiting the detection probe 10 while facilitating the up and down movement of the detection probe 10 in the through hole 12, and preventing the detection probe 10 from being easily pulled out of the through hole 12 when encountering a concave or convex ground. It should be noted that the limiting block 101 can be a square protrusion or a waist round rod, or an irregularly shaped protrusion, as long as it can play the above-mentioned limiting role, and the shape of the limiting block is not specifically required.

[0049] Preferably, the limiting block 101 is connected with a spring at the lower end of the receiving space 110 of the crossbar 11, and under the joint action of the spring and the limiting block 101, the fixed distance between the detection probe 10 and the bridge surface is ensured, that is, the lifting value of the detection probe 10 from the bridge surface.

[0050] In some preferred embodiments, referring to Figure 1 As shown in the figure, the walking mechanism 2 comprises:

[0051] The crossbeam 20 is provided with a port for connecting the scanner 1;

[0052] Two inclined beams 21 are connected with the crossbeam 20 and form a triangular structure;

[0053] Two load wheels 22 are connected at the two ends of the crossbeam 20 respectively;

[0054] A stabilizing wheel 23 is connected at the connection of the two inclined beams 21, and the axial directions of the load wheels 22 and the stabilizing wheel 23 are the same.

[0055] Specifically, the crossbeam 20 is provided with a male end, and the scanner 1 is provided with a female end, or the crossbeam 20 is provided with a female end, and the scanner 1 is provided with a male end, and the two are connected and fixed through the port; or a hook is provided on the crossbeam 20, and a hook hole is provided on the crossbar 11 of the scanner for hooking, or a hook is provided on the crossbar 11 of the scanner, and a corresponding hook hole is provided on the crossbeam 20.

[0056] For the overall structure of the walking mechanism 2, one crossbeam 20 and two inclined beams 21 form a triangle, because the triangle is stable, and three points determine a plane, so the walking mechanism 2 can basically adapt to the bridge surface while maintaining stability. Of course, the walking mechanism 2 can also adopt a rectangular structure or other walking mechanisms.

[0057] In some preferred embodiments, an encoder 24 is provided on the stabilizing wheel 23, and the encoder 24 is connected with the scanner 1.

[0058] Specifically, the encoder 24 can adopt a high-resolution photoelectric encoder. The function of the encoder 24 is to accurately record the longitudinal distance of the walking device, and at the same time trigger the data acquisition of the detection probe 10 on the scanner 1. The encoder 24 can accurately encode the forward distance, which is beneficial to the calculation of various parameters.

[0059] In some preferred embodiments, the step marking mechanism 3 comprises:

[0060] The marking device 31 has a nozzle facing the steel bridge deck;

[0061] The host computer 30 is connected with the scanner 1 and the marking device 31, and is used to receive the detection signal of the detection probe 10, and control the marking device 31 to spray ink when the detection probe 10 detects that the steel bridge deck or the U-rib has defects.

[0062] Specifically, the marking device 31 has a nozzle facing the bridge deck and maintaining a fixed height and angle relative to the bridge deck. Preferably, the nozzle is located in front of the stabilizing wheel 23, that is, at the center line position of the scanner 1. In the case that the detection probe 10 detects an abnormal magnetic stress signal, through distance delay, when the marking device 31 reaches the longitudinal position of the magnetic signal anomaly, the system host computer 30 controls the marking device 31 to mark a mark on the bridge deck. This mark is beneficial to marking special positions such as starting point, ending point, signal anomaly point, and is very beneficial to re-inspection. Ink or paint with bright color and not easy to wipe off can be used as the mark.

[0063] In some preferred embodiments, the host computer 30 also pre-stores the coordinates of each detection probe 10; the host computer 30 is also used to obtain the detection probe 10 that detects that the steel bridge deck or the U-rib has defects according to the detection signal and the pre-stored coordinates, and adjust the nozzle to spray towards the steel bridge deck below the detection probe 10.

[0064] Specifically, when one or more detection probes 10 on the scanner 1 detect an anomaly, the host computer 30 receives the signal, and conveys the coordinates of the detection probe 10 that detects the anomaly to the marking device 31, and the marking device 31 adjusts the ink jet to spray ink marks to the abnormal area, and prepares for re-inspection and the next step of the owner.

[0065] In some preferred embodiments, the host computer 30 is also provided with a positioning system.

[0066] Specifically, the positioning system can accurately position the real-time position of the scanning device. The positioning system can adopt Beidou satellite positioning system, or other positioning systems, or 5G related positioning technology and system.

[0067] After scanning one lane, the bridge deck magnetic signal cloud chart of this lane can be obtained. By scanning all lanes in turn, the bridge deck top surface scanning results of the whole bridge lane can be obtained. Through the analysis of the magnetic cloud chart, various useful signals can be obtained to determine the fatigue damage area of the bridge deck, and even the area where the crack is generated. Through the position of the encoder 24 (X axis) and the position of the detection probe 10 (Y axis), and the marks left by the marking device 31 during the detection process, the abnormal area can be conveniently determined for the owner to carry out the next step of processing.

[0068] Except for special description, all scanning devices are made of non-magnetic materials. At the same time, the scanning device adopts a detachable design, which is very beneficial to the transportation, assembly and preservation of the instrument. Under normal circumstances, the device can be hung behind a car or a pickup truck or a work vehicle, and can be pulled by the vehicle to follow the vehicle to improve the detection efficiency. In special cases, the system can also use the method of manpower to carry out scanning detection.

[0069] In the description of the present application, it should be noted that the terms "upper", "lower" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise expressly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0070] It should be noted that in the present application, relational terms such as "first" and "second" and the like are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device. Without more limitations, the element defined by the sentence "including a…" does not exclude the presence of another identical element in the process, method, article or device including the element.

[0071] The foregoing detailed description of the application has been presented for purposes of illustration and description. Various modifications and changes can be made to these embodiments without departing from the spirit and scope of the application. It is intended that the scope of the application should not be limited by the particular representative embodiments described above.

Claims

1. A scanning device for rapid detection of steel bridge decks and U-ribs, characterized in that: It includes: Walking mechanism (2); A scanner (1), the scanner (1) comprising a crossbar (11) and a plurality of detection probes (10), the detection probes (10) being spaced apart along the length direction of the crossbar (11), and the crossbar (11) being provided on the walking mechanism (2); The walking mechanism (2) comprises: A crossbeam (20), wherein the crossbeam (20) is provided with a port for connecting to the scanner (1); Two oblique beams (21), the two oblique beams (21) are connected to the cross beam (20) to form a triangular structure; a step-counting marking mechanism (3), the step-counting marking mechanism (3) being located on the walking mechanism (2), the step-counting marking mechanism (3) being connected to the scanner (1), and being used to mark the steel bridge deck when the detection probe (10) detects defects in the steel bridge deck or the U-rib; The crossbar (11) is provided with a through hole (12) perpendicular to the horizontal plane; The detection probe (10) comprises a detection rod (103), a height-fixing wheel (102) and a magnetic memory probe (100); the outer diameter of the detection rod (103) is smaller than the through hole (12), and the detection rod (103) is passed through the through hole (12); the height-fixing wheel (102) and the magnetic memory probe (100) are both arranged on the detection rod (103); A receiving space (110) is provided in the middle of the crossbar (11), and the through hole (12) passes through the receiving space (110); A limit block (101) is provided on the detection rod (103), and the limit block (101) is located in the receiving space (110); The step counting and marking mechanism (3) comprises: a marking device (31), wherein the nozzle of the marking device (31) faces the steel bridge deck; a host (30) connected to the scanner (1) and the marking device (31), the host (30) being used to receive a detection signal from the detection probe (10), and to control the marking device (31) to make a mark when the detection probe (10) detects a defect in the steel bridge deck or the U-rib; The host (30) also pre-stores the coordinates of each detection probe (10); The host (30) is further used to obtain the detection probe (10) that detects defects in the steel bridge deck or U-rib based on the detection signal and pre-stored coordinates, and adjust the direction of the nozzle to spray toward the steel bridge deck below the detection probe (10).

2. The scanning device for rapid inspection of steel bridge decks and U-ribs according to claim 1, characterized in that: There are two cross bars (11), the two cross bars (11) are arranged horizontally, and one of the cross bars (11) is movably assembled on the other cross bar (11).

3. The scanning device for rapid inspection of steel bridge decks and U-ribs according to claim 1, characterized in that: One of the cross bars (11) has a plurality of through holes (13) distributed along its length, and the other cross bar (11) has at least one through hole (13) distributed along its length. The two cross bars (11) are fixed by pins through the through holes (13).

4. The scanning device for rapid inspection of steel bridge decks and U-ribs according to claim 1, characterized in that: The walking mechanism (2) comprises: Road wheels (22), there are two road wheels (22), which are respectively connected to both ends of the crossbeam (20); A stabilizing wheel (23) is connected to a connection point between the two oblique beams (21), and the road wheel (22) and the stabilizing wheel (23) have the same axial direction.

5. The scanning device for rapid inspection of steel bridge decks and U-ribs according to claim 4, characterized in that: An encoder (24) is provided on the stabilizing wheel (23), and the encoder (24) is connected to the scanner (1).

6. The scanning device for rapid inspection of steel bridge decks and U-ribs according to claim 1, characterized in that: The host (30) is also provided with a positioning system.

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