Steel bridge deck fatigue crack reinforcing device based on piezoelectric sensing monitoring and electromagnetic damping

Abstract

The invention discloses a steel bridge deck fatigue crack reinforcing device based on piezoelectric sensing monitoring and electromagnetic damping, and the device achieves the active suppression through the cooperation of an electromagnetic damping system and a piezoelectric sensing monitoring system. The piezoelectric sensing monitoring system is provided with a compression deformation monitoring module and a tensile deformation monitoring module, and the compression deformation monitoring module and the tensile deformation monitoring module sense the deformation direction of the bridge floor in real time through a piezoelectric sensor; the electromagnetic damping system is provided with a main electromagnet and an auxiliary electromagnet, and the current direction and magnitude of the electromagnets are regulated according to piezoelectric signals, so that repulsion or attraction force is generated to counteract deformation. According to the method, the stress concentration of the crack tip can be actively reduced, the crossing from traditional passive reinforcement to active deformation suppression is realized, and the problem that the out-of-plane deformation cannot be suppressed by a traditional passive reinforcement technology is solved.

Description

Technical Field

[0001] The present invention relates to a fatigue crack reinforcement device for steel bridge decks, and particularly to a fatigue crack reinforcement device for steel bridge decks based on piezoelectric sensing monitoring and electromagnetic damping. Background Art

[0002] Orthotropic steel bridge decks have been widely used in the field of bridge engineering due to their advantages such as light self-weight and large flexural stiffness. The top plate of the steel bridge deck is welded to the U-ribs. Under the combined action of factors such as welding residual stress and vehicle load, fatigue cracks are extremely likely to occur. Fatigue cracks usually initiate at the weld toes or weld roots on the outer or inner sides of the U-ribs, and once initiated, they will rapidly propagate, greatly endangering the durability of the steel bridge deck and the safety of the bridge structure.

[0003] For the fatigue cracks of steel bridge decks, currently commonly used reinforcement methods include crack arrest hole method, crack welding method, steel plate reinforcement method, FRP reinforcement method, etc. The crack arrest hole method is a temporary crack arrest measure. It drills holes at the crack tips to eliminate sharp stress concentration points, transfers the high-stress area at the crack tips to the hole edges, thereby delaying crack propagation. However, engineering practice shows that the crack arrest effect of the crack arrest hole method is relatively limited. After a period of service, cracks will re-initiate at the edges of the crack arrest holes and continue to propagate.

[0004] The crack welding method melts the crack area and the filling material (such as welding wire / electrode) at high temperature, so that the metals on both sides of the crack are re-bonded to eliminate the crack defect. In theory, the crack welding method can completely restore the load-bearing capacity of the structure. However, restricted by factors such as welding technology, in-situ bridge welding environment, and welding residual stress, after a period of service, cracks will re-initiate and propagate again in the re-welded area.

[0005] The steel plate reinforcement method and the FRP reinforcement method have similar principles, that is, by externally pasting a reinforcement steel plate or FRP cloth / plate to restore the strength of the cracked structure. The core is to share the load through the newly added steel plate or FRP material and reduce the stress level in the original crack area. Fatigue tests and engineering practice show that pasting steel plates or FRP materials can effectively reduce the crack propagation rate. However, with the continuous application of fatigue loads, cracks will gradually expand beyond the reinforcement area and continue to propagate at a relatively fast rate.

[0006] In summary, the existing reinforcement methods are difficult to achieve ideal reinforcement effects. The fundamental reason is that the out-of-plane deformation of the structure caused by external loads still exists. In other words, the existing reinforcement methods belong to "passive" reinforcement methods, and their starting point is to reduce the stress concentration at the crack tips, rather than actively reducing the out-of-plane deformation of the structure caused by external loads. Summary of the Invention

[0007] Object of the Invention: The object of the present invention is to provide a fatigue crack reinforcement device for steel bridge decks that can actively reduce the out-of-plane deformation of the structure caused by external loads.

[0008] Technical solution: A fatigue crack reinforcement device for steel bridge decks based on piezoelectric sensing monitoring and electromagnetic damping of the present invention is installed at the bottom of the top plate of the steel bridge deck and between two U-shaped ribs;

[0009] The fatigue crack reinforcement device for the steel bridge deck includes a top plate connecting plate fixed to the bottom of the top plate of the steel bridge deck and a U-rib connecting plate fixed to the side surface of the U-rib. The U-rib connecting plate and the top plate connecting plate are connected by a group of piezoelectric sensing monitoring systems and at least two groups of electromagnetic damping systems;

[0010] The electromagnetic damping system has a first main sleeve and a first sub-sleeve sleeved with each other, and single-arm hinge joints at both ends of the electromagnetic damping system; a main electromagnet and a sub-electromagnet are respectively fixed in the first main sleeve and the first sub-sleeve, and there is a gap between the main and sub-electromagnets; the two single-arm hinge joints are respectively hinged to the top plate connecting plate and the U-rib connecting plate;

[0011] The piezoelectric sensing monitoring system has a signal analysis module, two relatively arranged fixed seats, and double-arm hinge joints at both ends of the piezoelectric sensing monitoring system; a compression deformation monitoring module and a tensile deformation monitoring module are arranged side by side between the two fixed seats, and the compression deformation monitoring module and the tensile deformation monitoring module use piezoelectric sensors to monitor compression or tensile signals; the two double-arm hinge joints are respectively hinged to the top plate connecting plate and the U-rib connecting plate;

[0012] The signal analysis module includes a piezoelectric signal processing module and an electromagnet control module; if the compression deformation monitoring module detects a compression signal, the piezoelectric signal processing module sends an instruction to the electromagnet control module to control the current direction in the main electromagnet and the sub-electromagnet, so as to achieve repulsion between the same poles and reduce the compression deformation; if the tensile deformation monitoring module detects a tensile signal, the piezoelectric signal processing module sends an instruction to the electromagnet control module to control the current direction in the main electromagnet and the sub-electromagnet, so as to achieve attraction between opposite poles and reduce the tensile deformation; the magnitude of the current in the main electromagnet and the sub-electromagnet is determined according to the strength of the piezoelectric signal, and the stronger the piezoelectric signal, the greater the current.

[0013] Further, the electromagnetic damping system is lengthened through a cylindrical assembled connector, and the lengthening is realized based on the first sliding grooves and first convex teeth adapted to both ends of the cylindrical assembled connector, and the first sliding grooves or first convex teeth correspondingly arranged on the sleeve and the single-arm hinge joint.

[0014] Further, the piezoelectric sensing monitoring system is lengthened through a square column assembled connector, and the lengthening is realized based on the second sliding grooves and second convex teeth adapted to both ends of the square column assembled connector, and the second sliding grooves or second convex teeth correspondingly arranged on the fixed seat and the double-arm hinge joint.

[0015] Further, the compression deformation monitoring module includes a second main sleeve and a second auxiliary sleeve which are sleeved with each other, and the second main sleeve and the second auxiliary sleeve are respectively fixed to two fixed seats; a first piezoelectric sensor is arranged in the second main sleeve, the first piezoelectric sensor is supported by a spring and a pressure pad, and one end of the second auxiliary sleeve facing the first piezoelectric sensor is closed; the spring is in a pre-compressed state.

[0016] Further, the tensile deformation monitoring module includes a third main sleeve and a pull rod, and the third main sleeve and the pull rod are respectively fixed to two fixed seats; a second piezoelectric sensor, a reaction force application pad and a reaction force fixed end are sequentially arranged in the third main sleeve, a reaction force transmission spring is arranged between the reaction force application pad and the reaction force fixed end, and one end of the third main sleeve facing the second piezoelectric sensor is closed; the pull rod passes through the third main sleeve and the reaction force application pad and is fixedly connected to the reaction force fixed end; the reaction force transmission spring is in a pre-compressed state.

[0017] Further, when the piezoelectric signal remains stable for more than a set time, the piezoelectric signal processing module sends an instruction to the electromagnet control module to stop inputting current into the main electromagnet and the auxiliary electromagnet.

[0018] Further, the top plate connecting plate is fixed to the bottom of the steel bridge deck top plate by a plurality of magnetic seats, and the plurality of magnetic seats are distributed along the edge of the top plate connecting plate.

[0019] Further, hinge connectors are fixed on the top plate connecting plate and the U-rib connecting plate, and the hinge connectors are hinged to the corresponding single-arm hinge head or double-arm hinge head through hinge connecting bearings.

[0020] Further, the hinge connector is fixed to the top plate connecting plate or the U-rib connecting plate by a connecting bolt, a radial fixing bolt rod connecting hole is formed in the connecting bolt, a corresponding fixing bolt rod passing hole is formed in the hinge connector, and the fixing bolt rod is inserted into the fixing bolt rod passing hole and the fixing bolt rod connecting hole to prevent the connecting bolt from loosening.

[0021] Further, the steel bridge deck fatigue crack reinforcement device based on piezoelectric sensing monitoring and electromagnetic damping further includes a power supply and control module, and the power supply and control module is used for accumulating and storing the magnitude and the number of times of the piezoelectric signals of the piezoelectric sensors, and when a communication connection is established with the mobile phone terminal, synchronously uploading the monitoring data to the APP client; the APP client can be used to detect whether the piezoelectric signal processing module and the electromagnet control module are working properly, and to zero the piezoelectric signals of the piezoelectric sensors to complete the initial setting of the steel bridge deck fatigue crack reinforcement device.

[0022] Beneficial effects: Compared with the prior art, the present invention has the following remarkable advantages: The present invention can actively control the out-of-plane deformation. Specifically, through the synergistic effect of the electromagnetic damping system and the piezoelectric sensing and monitoring system, it can real-time sense the deformation state of the steel bridge deck, and actively apply the same-sex electromagnetic repulsion or opposite-sex electromagnetic attraction, while adaptively adjusting the magnitude of the force, effectively offsetting the out-of-plane deformation caused by external loads, and fundamentally reducing the stress concentration at the crack tip. Description of the Drawings

[0023] Figure 1 is a schematic structural diagram of a fatigue crack reinforcement device for a steel bridge deck based on piezoelectric sensing and monitoring and electromagnetic damping provided by an embodiment of the present invention;

[0024] Figure 2 is Figure 1 front view;

[0025] Figure 3 is a schematic structural diagram of the electromagnetic damping system in an embodiment of the present invention;

[0026] Figure 4 is a schematic structural diagram of the piezoelectric sensing and monitoring system in an embodiment of the present invention;

[0027] Figure 5 is a schematic structural diagram of the tensile deformation monitoring module and the compressive deformation monitoring module in an embodiment of the present invention;

[0028] Figure 6 is an exploded view of the tensile deformation monitoring module in an embodiment of the present invention;

[0029] Figure 7 is a schematic structural diagram of the connection structure between the U-rib fixing plate and the articulated connection head in an embodiment of the present invention;

[0030] Figure 8 is a schematic structural diagram of the connection structure between the single-arm type, double-arm type hinge joint and the articulated connection head in an embodiment of the present invention;

[0031] Figure 9 is a schematic structural diagram of an orthotropic steel bridge deck with cracks in an embodiment of the present invention;

[0032] Figure 10 is a schematic diagram of the U-rib fixing plate installed on the side of the U-rib in an embodiment of the present invention;

[0033] Figure 11 is a schematic diagram of the top plate connecting plate installed at the bottom of the steel bridge deck top plate in an embodiment of the present invention;

[0034] Figure 12 is a schematic diagram of the fatigue crack reinforcement device installed on the orthotropic steel bridge deck in an embodiment of the present invention. Detailed Embodiments

[0035] The present invention will be further described below in conjunction with the accompanying drawings.

[0036] Accompanying Figures 1 to 12 The reference numerals in the drawings are as follows:

[0037] 1, electromagnetic damping system; 11, first main sleeve; 111, main electromagnet; 12, first sub-sleeve; 121, sub-electromagnet; 13, cylindrical assembled connector; 131, first chute; 132, first convex tooth; 14, single-arm hinge joint; 15, first hinge bearing hole;

[0038] 2, piezoelectric sensing and monitoring system; 21, compression deformation monitoring module; 211, second main sleeve; 212, second sub-sleeve; 213, first piezoelectric sensor; 214, pressure pad; 215, spring; 22, tensile deformation monitoring module; 221, third main sleeve; 222, pull rod; 2221, first through hole; 2222, second through hole; 223, second piezoelectric sensor; 224, reaction force fixed end; 225, reaction force transfer spring; 226, reaction force application pad; 23, square column assembled connector; 231, second chute; 232, second convex tooth; 24, double-arm hinge joint; 25, second hinge bearing hole; 26, signal analysis module; 261, piezoelectric signal processing module; 262, electromagnet control module;

[0039] 3, roof connecting plate; 31, magnetic seat; 32, first threaded hole;

[0040] 4, U-rib fixing plate; 41, connecting bolt; 411, fixing bolt rod; 412, fixing bolt rod connection hole; 413, fixing bolt rod through hole; 42, second threaded hole; 43, third threaded hole; 44, fourth threaded hole;

[0041] 5, hinge connection head; 51, third hinge bearing hole; 52, hinge connection bearing;

[0042] 6, power supply and control module;

[0043] 7, orthotropic steel bridge deck; 71, paving layer; 72, steel bridge deck roof; 73, U-rib;

[0044] 8, fatigue crack.

[0045] As Figure 9 shown in the orthotropic steel bridge deck 7, a fatigue crack 8 is formed at the connection position of the steel bridge deck roof 72 and the U-rib 73, and a paving layer 71 is provided on the top of the steel bridge deck roof 72.

[0046] As Figure 1 、 Figure 2 and Figure 12As shown in the figure, an embodiment of the present invention provides a fatigue crack reinforcement device for a steel bridge deck based on piezoelectric sensing monitoring and electromagnetic damping. The fatigue crack reinforcement device for the steel bridge deck is installed at the bottom of the steel bridge deck top plate 72 and located between two U-shaped ribs 73, and includes a power supply and control module 6, a top plate connecting plate 3 fixed to the bottom of the steel bridge deck top plate 72, and a U-shaped rib connecting plate 4 fixed to the side surface of the U-shaped rib 73. The U-shaped rib connecting plate 4 and the top plate connecting plate 3 are connected by a set of piezoelectric sensing monitoring systems 2 and two sets of electromagnetic damping systems 1 (since the fatigue crack has two tips, the electromagnetic damping systems 1 need to be arranged in pairs).

[0047] As Figure 3 shown, the electromagnetic damping system 1 has a first main sleeve 11 and a first sub-sleeve 12 that are sleeved with each other, and a single-arm hinge joint 14 located at both ends of the electromagnetic damping system 1. A first hinge bearing hole 15 is provided on the single-arm hinge joint 14. A main electromagnet 111 is fixed inside the first main sleeve 11, and a sub-electromagnet 121 is fixed inside the first sub-sleeve 12. The electromagnetic damping system 1 is lengthened through a cylindrical assembled connector 13. Specifically, both ends of the cylindrical assembled connector 13 have a first sliding groove 131 and a first convex tooth 132 that are adapted to each other. The ends of the first main sleeve 11 and the first sub-sleeve 12 are provided with first convex teeth 132, and the end of the single-arm hinge joint 14 is provided with a first sliding groove 131. The connection between each component is realized based on the insertion and cooperation of the first sliding groove 131 and the first convex tooth 132.

[0048] As Figure 4 and Figure 5 shown, the piezoelectric sensing monitoring system 2 has a signal analysis module 26, two relatively arranged fixed seats, and a double-arm hinge joint 24 located at both ends of the piezoelectric sensing monitoring system 2. A second hinge bearing hole 25 is provided on the double-arm hinge joint 24. The piezoelectric sensing monitoring system 2 is lengthened through a square column assembled connector 23. Specifically, both ends of the square column assembled connector 23 have a second sliding groove 231 and a second convex tooth 232 that are adapted to each other. One end of the double-arm hinge joint 24 is fixedly connected to the corresponding fixed seat, the other end of the double-arm hinge joint 24 is provided with a second convex tooth 232, and the corresponding fixed seat is provided with a second sliding groove 231. The connection between each component is realized based on the insertion and cooperation of the second sliding groove 231 and the second convex tooth 232. The signal analysis module 26 is arranged inside the lower fixed seat and includes a piezoelectric signal processing module 261 and an electromagnet control module 262.

[0049] A compression deformation monitoring module 21 and a tensile deformation monitoring module 22 are arranged side by side between the two fixed seats.

[0050] Specifically, the compression deformation monitoring module 21 includes a second main sleeve 211 and a second sub-sleeve 212 that are sleeved with each other. The second main sleeve 211 and the second sub-sleeve 212 are respectively fixed to two fixed seats. A first piezoelectric sensor 213 is arranged in the second main sleeve 211. The first piezoelectric sensor 213 is supported by a spring 215 and a pressure-applying gasket 214. One end of the second sub-sleeve 212 facing the first piezoelectric sensor 213 is closed.

[0051] Combined with Figure 6 , the tensile deformation monitoring module 22 includes a third main sleeve 221 and a pull rod 222. The third main sleeve 221 and the pull rod 222 are respectively fixed to two fixed seats. A second piezoelectric sensor 223, a reaction force applying gasket 226, and a reaction force fixed end 224 are sequentially arranged in the third main sleeve 221. A reaction force transmission spring 225 is arranged between the reaction force applying gasket 226 and the reaction force fixed end 224. One end of the third main sleeve 221 facing the second piezoelectric sensor 223 is closed. A second through hole 2222 for the pull rod 222 to pass through is opened on the third main sleeve 221. A first through hole 2221 for the pull rod 222 to pass through is opened on the reaction force applying gasket 226. The pull rod 222 passes through the third main sleeve 221 and the reaction force applying gasket 226 and is fixedly connected to the reaction force fixed end 224.

[0052] As Figure 11 shown, the top plate connecting plate 3 is fixed to the bottom of the steel bridge deck top plate 72 by a plurality of magnetic seats 31. The plurality of magnetic seats 31 are distributed along the edge of the top plate connecting plate 3. A first threaded hole 32 for fixing the articulated connecting head 5 is opened on the top plate connecting plate 3.

[0053] As Figures 7 to 10 shown, a through fourth threaded hole 44 is opened on the U-rib 73. A second threaded hole 42 for fixing the articulated connecting head 5 is opened on the U-rib fixing plate 4. A third threaded hole 43 and a third articulated bearing hole 51 are arranged on the articulated connecting head 5. The articulated connecting head 5 is articulated with the corresponding single-arm articulated head 14 or double-arm articulated head 24 through an articulated connecting bearing 52. The articulated connecting head 5 is fixed to the top plate connecting plate 3 or the U-rib fixing plate 4 by a connecting bolt 41. The number of articulated connecting heads 5 on the top plate connecting plate 3 and the U-rib fixing plate 4 matches the number of groups of the piezoelectric sensing monitoring system 2 and the electromagnetic damping system 1.

[0054] A radial fixing bolt connection hole 412 is opened on the connecting bolt 41. A corresponding fixing bolt passing hole 413 is opened on the articulated connecting head 5. A fixing bolt 411 is inserted into the fixing bolt passing hole 413 and the fixing bolt connection hole 412 to prevent the connecting bolt 41 from loosening.

[0055] The installation method of the steel bridge deck fatigue crack reinforcement device described in the embodiment of the present invention is as follows.

[0056] Determine the installation position of the steel bridge deck fatigue crack reinforcement device according to the position of the fatigue crack 8 on the orthotropic steel bridge deck 7. According to the position of the second threaded hole 42 on the U-rib fixing plate 4, lay out a line on the U-rib 73 to determine the position of the fourth threaded hole 44 and drill a hole.

[0057] Use the connecting bolt 41 to connect and fix the articulated connector 5, the U-rib fixing plate 4 and the U-rib 73, and further fix the connecting bolt 41 and the articulated connector 5 with the fixing bolt rod 411.

[0058] Determine the installation position of the top plate connecting plate 3 on the steel bridge deck top plate 72 at the middle position between adjacent U-ribs 73, and fix the top plate connecting plate 3 on the steel bridge deck top plate 72 through the magnetic base 31. Use the connecting bolt 41 to fix the articulated connector 5 on the top plate connecting plate 3, and further fix the connecting bolt 41 and the articulated connector 5 with the fixing bolt rod 411.

[0059] Use the articulated connecting bearing 52 to connect the single-arm hinge head 14 and the double-arm hinge head 24 to the articulated connector 5 respectively, and use a certain number of cylindrical assembled connectors 13 and square column assembled connectors 23 to complete the installation of the electromagnetic damping system 1 and the piezoelectric sensing monitoring system 2. After installation, ensure that there is a gap of 1-2 mm between the main electromagnet 111 and the sub-electromagnet 121, and at the same time ensure that the spring 215 and the reaction force transmission spring 225 are in a pre-compressed state.

[0060] Connect the power supply and control module 6 to the auxiliary power supply of the bridge structure to ensure power supply. Connect the power supply and control module 6 through the corresponding mobile phone APP, check whether the piezoelectric signal processing module 261 and the electromagnet control module 262 are working properly, and zero the piezoelectric signals of the first piezoelectric sensor 213 and the second piezoelectric sensor 223 to complete the initial setting of the steel bridge deck fatigue crack reinforcement device.

[0061] When the vehicle load passes directly above the fatigue crack 8, according to the basic theory of structural mechanics, the orthotropic steel bridge deck 7 will undergo out-of-plane deformation. Specifically, the angle between the steel bridge deck top plate 72 and the U-rib 73 at the fatigue crack 8 will become smaller. At this time, the piezoelectric sensing monitoring system 2 will be compressed, and a piezoelectric signal will be generated inside the first piezoelectric sensor 213 and transmitted to the piezoelectric signal processing module 261, while the second piezoelectric sensor 223 will not generate a piezoelectric signal. After receiving the piezoelectric signal transmitted by the first piezoelectric sensor 213, the piezoelectric signal processing module 261 determines the out-of-plane deformation characteristics of the orthotropic steel bridge deck 7 based on the piezoelectric signal and sends a control instruction to the electromagnet control module 262, adaptively controlling the current direction and magnitude in the main electromagnet 111 and the auxiliary electromagnet 121 according to the strength of the piezoelectric signal, achieving repulsion between like poles, reducing the compressive deformation, and realizing the active reinforcement of the fatigue crack 8.

[0062] When the piezoelectric signal transmitted inside the first piezoelectric sensor 213 remains stable for more than 1 s, it indicates that the vehicle load has passed. The piezoelectric signal processing module 261 immediately sends an instruction to the electromagnet control module 262 to stop inputting current into the main electromagnet 111 and the auxiliary electromagnet 121, and the device returns to the initial state.

[0063] If the second piezoelectric sensor 223 generates a piezoelectric signal and the first piezoelectric sensor 213 does not generate a piezoelectric signal, the current direction and magnitude in the main electromagnet 111 and the auxiliary electromagnet 121 are adaptively controlled according to the strength of the piezoelectric signal to achieve attraction between opposite poles and reduce the tensile deformation. When the piezoelectric signal transmitted inside the second piezoelectric sensor 223 remains stable for more than 1 s, similarly, the piezoelectric signal processing module 261 sends an instruction to the electromagnet control module 262 to stop inputting current into the main electromagnet 111 and the auxiliary electromagnet 121.

[0064] The power supply and control module 6 accumulates and stores the magnitude and generation times of the piezoelectric signals in the first piezoelectric sensor 213 and the second piezoelectric sensor 223. When the user connects the power supply and control module 6 through a Bluetooth signal using a mobile phone APP, the data stored in the power supply and control module 6 will be synchronously uploaded to the APP client. The user can view the magnitude and generation times of the piezoelectric signals in the first piezoelectric sensor 213 and the second piezoelectric sensor 223 in real time and can conduct further analysis based on this data.

[0065] The steel bridge deck fatigue crack reinforcement device provided by the embodiment of the present invention has the following advantages:

[0066] (1) Active control of out-of-plane deformation: Through the synergistic effect of the electromagnetic damping system and the piezoelectric sensor monitoring system, the deformation state of the steel bridge deck can be sensed in real time, and the same-sex electromagnetic repulsion or opposite-sex electromagnetic attraction can be actively applied to effectively offset the out-of-plane deformation caused by external loads, fundamentally reducing the stress concentration at the crack tip, which is significantly better than the traditional passive reinforcement method.

[0067] (2) Adaptive real-time control: Using the piezoelectric sensor signal feedback mechanism, the device can adaptively adjust the direction and intensity of the electromagnetic force according to the dynamic changes of the vehicle load. When the piezoelectric signal is stable for more than 1 second (indicating that the load has passed), the electromagnet current is automatically cut off to avoid energy waste and realize intelligent closed-loop control.

[0068] (3) Modular assembly and remote monitoring: The slide-groove plug-in connector and hinged structure are used to support rapid modular installation. The piezoelectric signal data is collected synchronously through a mobile phone APP to achieve long-term dynamic monitoring and big data analysis of the reinforcement effect, providing a scientific basis for bridge operation and maintenance decisions.

[0069] (4) Improved compatibility and safety: The hybrid connection method of magnetic base and bolts can not only meet the complex structural installation requirements of steel bridge decks, but also avoid the secondary residual stress problems that may be caused by traditional welding reinforcement, reduce the risk of damage to the original structure, and extend the overall service life of the bridge.

[0070] In summary, the present invention achieves a transition from passive reinforcement to active suppression through the integrated design of "sensing-feedback-regulation", providing an innovative solution for the management of fatigue cracks in steel bridge decks.

Claims

1. A fatigue crack reinforcement device for steel bridge decks based on piezoelectric sensing monitoring and electromagnetic damping, characterized in that, It is installed at the bottom of the steel bridge deck top plate (72) and between two U-shaped ribs (73). The steel bridge deck fatigue crack reinforcement device includes a top plate connecting plate (3) fixed to the bottom of the steel bridge deck top plate (72) and a U-shaped rib connecting plate (4) fixed to the side surface of the U-shaped rib (73). The U-shaped rib connecting plate (4) and the top plate connecting plate (3) are connected by a set of piezoelectric sensing and monitoring systems (2) and at least two sets of electromagnetic damping systems (1). The electromagnetic damping system (1) has a first main sleeve (11) and a first sub-sleeve (12) sleeved with each other, and single-arm hinge joints (14) at both ends of the electromagnetic damping system (1); a main electromagnet (111) and a sub-electromagnet (121) are respectively fixed in the first main sleeve (11) and the first sub-sleeve (12), and there is a gap between the main and sub-electromagnets; the two single-arm hinge joints (14) are respectively hinged to the top plate connecting plate (3) and the U-shaped rib connecting plate (4). The piezoelectric sensing and monitoring system (2) has a signal analysis module (26), two relatively arranged fixing seats, and double-arm hinge joints (24) at both ends of the piezoelectric sensing and monitoring system (2); a compression deformation monitoring module (21) and a tensile deformation monitoring module (22) are arranged side by side between the two fixing seats, and the compression deformation monitoring module (21) and the tensile deformation monitoring module (22) use piezoelectric sensors to monitor compression or tensile signals; the two double-arm hinge joints (24) are respectively hinged to the top plate connecting plate (3) and the U-shaped rib connecting plate (4). The signal analysis module (26) includes a piezoelectric signal processing module (261) and an electromagnet control module (262); if the compression deformation monitoring module (21) detects a compression signal, the piezoelectric signal processing module (261) sends an instruction to the electromagnet control module (262) to control the current direction in the main electromagnet (111) and the sub-electromagnet (121) to achieve repulsion between like poles and reduce the compression deformation; if the tensile deformation monitoring module (22) detects a tensile signal, the piezoelectric signal processing module (261) sends an instruction to the electromagnet control module (262) to control the current direction in the main electromagnet (111) and the sub-electromagnet (121) to achieve attraction between opposite poles and reduce the tensile deformation; the magnitude of the current in the main electromagnet (111) and the sub-electromagnet (121) is determined according to the strength of the piezoelectric signal, and the stronger the piezoelectric signal, the greater the current.

2. The steel bridge deck fatigue crack reinforcement device based on piezoelectric sensing monitoring and electromagnetic damping according to claim 1, characterized in that The electromagnetic damping system (1) is lengthened through a cylindrical assembled connector (13), and the lengthening is achieved based on the first sliding grooves (131) and the first convex teeth (132) adapted to both ends of the cylindrical assembled connector (13), and the first sliding grooves (131) or the first convex teeth (132) correspondingly arranged on the sleeve and the single-arm hinge joint (14).

3. The fatigue crack reinforcement device for steel bridge decks based on piezoelectric sensing monitoring and electromagnetic damping according to claim 1, wherein The piezoelectric sensing and monitoring system (2) is lengthened through a square column assembled connector (23), and the lengthening is achieved based on the second sliding grooves (231) and the second convex teeth (232) adapted to both ends of the square column assembled connector (23), and the second sliding grooves (231) or the second convex teeth (232) correspondingly arranged on the fixing seat and the double-arm hinge joint (24).

4. The fatigue crack reinforcement device for steel bridge decks based on piezoelectric sensing monitoring and electromagnetic damping according to claim 1, characterized in that, The compression deformation monitoring module (21) includes a second main sleeve (211) and a second sub-sleeve (212) which are sleeved with each other. The second main sleeve (211) and the second sub-sleeve (212) are respectively fixed to two fixed seats. A first piezoelectric sensor (213) is arranged in the second main sleeve (211). The first piezoelectric sensor (213) is supported by a spring (215) and a pressure-applying gasket (214). One end of the second sub-sleeve (212) facing the first piezoelectric sensor (213) is closed. The spring (215) is in a pre-compressed state.

5. The steel bridge deck fatigue crack reinforcement device based on piezoelectric sensing monitoring and electromagnetic damping according to claim 1, characterized in that, The tensile deformation monitoring module (22) includes a third main sleeve (221) and a pull rod (222). The third main sleeve (221) and the pull rod (222) are respectively fixed to two fixed seats. A second piezoelectric sensor (223), a reaction force applying gasket (226) and a reaction force fixed end (224) are sequentially arranged in the third main sleeve (221). A reaction force transmission spring (225) is arranged between the reaction force applying gasket (226) and the reaction force fixed end (224). One end of the third main sleeve (221) facing the second piezoelectric sensor (223) is closed. The pull rod (222) passes through the third main sleeve (221) and the reaction force applying gasket (226) and is fixedly connected to the reaction force fixed end (224). The reaction force transmission spring (225) is in a pre-compressed state.

6. The fatigue crack reinforcement device for steel bridge decks based on piezoelectric sensing monitoring and electromagnetic damping according to claim 1, characterized in that, When the piezoelectric signal remains stable for more than the set time, the piezoelectric signal processing module (261) sends an instruction to the electromagnet control module (262) to stop inputting current into the main electromagnet (111) and the sub-electromagnet (121).

7. The steel bridge deck fatigue crack reinforcement device based on piezoelectric sensing monitoring and electromagnetic damping according to claim 1, characterized in that, The top plate connecting plate (3) is fixed to the bottom of the steel bridge deck top plate (72) by a plurality of magnetic seats (31). The plurality of magnetic seats (31) are distributed along the edge of the top plate connecting plate (3).

8. The steel bridge deck fatigue crack reinforcement device based on piezoelectric sensing monitoring and electromagnetic damping according to claim 1, characterized in that, A hinged connection head (5) is fixed on the top plate connecting plate (3) and the U-rib fixing plate (4). The hinged connection head (5) is hinged to the corresponding single-arm hinge head (14) or double-arm hinge head (24) through a hinged connection bearing (52).

9. The device for reinforcing fatigue cracks of a steel bridge deck based on piezoelectric sensing monitoring and electromagnetic damping according to claim 8, characterized in that The hinged connection head (5) is fixed to the top plate connecting plate (3) or the U-rib fixing plate (4) by a connecting bolt (41). A radial fixing bolt rod connection hole (412) is formed in the connecting bolt (41). A corresponding fixing bolt rod passing hole (413) is formed in the hinged connection head (5). The fixing bolt rod (411) is inserted into the fixing bolt rod passing hole (413) and the fixing bolt rod connection hole (412) to prevent the connecting bolt (41) from loosening.

10. The steel bridge deck fatigue crack reinforcement device based on piezoelectric sensing monitoring and electromagnetic damping according to any one of claims 1 to 9, characterized in that, It also includes a power supply and control module (6). The power supply and control module (6) is used to accumulate and store the magnitude and generation times of the piezoelectric signals of the piezoelectric sensors, and when a communication connection is established with the mobile phone terminal, synchronously upload the monitoring data to the APP client. The APP client can be used to detect whether the piezoelectric signal processing module (261) and the electromagnet control module (262) are working properly, and to zero the piezoelectric signals of the piezoelectric sensors to complete the initial setting of the steel bridge deck fatigue crack reinforcement device.

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