CN115331409B

CN115331409B - Cable force monitoring and early warning device and method for cable structure bridge

Info

Publication number: CN115331409B
Application number: CN202211245341.6A
Authority: CN
Inventors: 廖立勋; 袁浩允; 韩昊阳
Original assignee: CCCC Second Highway Engineering Co Ltd
Current assignee: CCCC Second Highway Engineering Co Ltd
Priority date: 2022-10-12
Filing date: 2022-10-12
Publication date: 2023-02-10
Anticipated expiration: 2042-10-12
Also published as: CN115331409A

Abstract

The invention belongs to the technical field of suspension bridge safety monitoring, and particularly relates to a cable structure bridge cable force monitoring and early warning device and method. The invention can perform early warning action when the bridge main body generates a 'Karman vortex street' phenomenon, on one hand, the possibility of safety accidents is reduced by monitoring and early warning the sling, and the bridge main body can be buffered in a vibration resisting way to a certain extent, on the other hand, the invention can monitor and warn that the sling is permanently stretched, and temporarily assists the sling to suspend and bear force on the bridge main body after the sling is permanently stretched, thereby achieving the effect of flexible compensation and giving more time for workers to maintain and overhaul the sling.

Description

Cable force monitoring and early warning device and method for cable structure bridge

Technical Field

The invention belongs to the technical field of suspension bridge safety monitoring, and particularly relates to a cable force monitoring and early warning device and method for a cable structure bridge.

Background

The suspension bridge is a flexible suspension system composed of components such as a main cable, a stiffening beam, a main tower, a saddle, an anchorage, a sling and the like, and the suspension bridge has poor stability compared with a bridge supported by a traditional pier because the load mode of the suspension bridge is the flexible suspension system.

Because the suspension bridge mainly bears the bridge main body through main cables and a plurality of slings, the stress monitoring of the cables is very necessary for the safety of the suspension bridge, and the main body is disclosed as follows: CN104777815B, discloses a suspension bridge cable safety comprehensive monitoring system and monitoring method, which is to monitor the stress on the suspension bridge cable by setting sensor units at different positions;

the suspension bridge is generally only provided with main tower supports near two sides of a shore, no pier is arranged below a bridge main body, so that the suspension bridge is generally wide below, when the side face of the bridge main body is subjected to wind force in the horizontal direction, a part of wind current flows from the upper side of the bridge main body and then generates a vortex, after the vortex leaves, the wind current flowing from the lower side of the bridge main body generates a new vortex, the vortex alternately appears up and down to form a 'karman vortex street', the bridge main body can pull all slings to continuously swing together, and the slings are easy to resonate with the bridge main body along with the increasing amplitude of the swing, so that the bridge main body is seriously broken, at the moment, the crane on the suspension bridge is very unsafe, the force on all slings is very uneven due to the swing of the bridge main body, particularly when the swing amplitude of the bridge main body is large, a part of the slings are permanently stretched, after the bridge main body is recovered to be stable, the slings are unevenly stressed on the bridge main body, if the slings are not timely handled, the safety of the slings is easily influenced for a long time, the safety of the bridge is easy to monitor, a single sensor, and a high-frequency vibration early warning device can not only solve the problem that the high-frequency early warning device and the early warning requirement of the high-early warning device.

Disclosure of Invention

The invention aims to solve the problems and provides a cable force monitoring and early warning device and method for a cable structure bridge, which can improve the safety and reliability.

In order to achieve the purpose, the invention adopts the following technical scheme: the utility model provides a cable structure bridge cable power monitoring early warning device, includes bridge main part, two main towers, main cable, a plurality of hoist cable and stiffening beam, the main cable sets up and is the arc in the top of two main towers and suspends the setting in midair, the stiffening beam sets up in the bridge main part, and the stiffening beam is connected with the main cable through a plurality of hoist cables jointly, two lie in the common fixed backup pad that is equipped with in bridge main part below between the main tower, the inside of bridge main part has been buried underground a plurality of empty boxes corresponding with the hoist cable, and the inside of each empty box all is fixed and is equipped with the copper ring, be fixed with a plurality of drums in the backup pad, each the terminal surface of drum all is fixed with the plastic box, and the inside of each plastic box all activity is equipped with neodymium iron boron magnet, be equipped with a set of first spring jointly between neodymium iron boron magnet bottom and the plastic box, each plastic box and drum all are equipped with buffering trigger mechanism jointly, two the lateral wall of main tower all is equipped with the LED early warning screen with a plurality of buffering trigger mechanism matched with, each temporary hoist mechanism that is connected with the hoist cable on the hoist cable, and warning mechanism is connected with the tensile mechanism that triggers the same side of crossing.

Preferably, each buffering trigger mechanism all is including setting up the elasticity gasbag between neodymium iron boron magnet and plastic case, the lateral wall of elasticity gasbag is pegged graft jointly with plastic case's lateral wall and is had intake pipe and outlet duct, and all is equipped with the check valve in intake pipe and the outlet duct, the drum is linked together with the outlet duct and sets up, the inside activity of drum is equipped with iron plate, and the lateral wall of iron plate cup joint with drum inner wall interference fit's rubber leather sheath, the lateral wall of drum is located the position of iron plate upside and has seted up the slowly-releasing bleeder vent, all fixed the insulating pad that is equipped with at the bottom of the lower extreme of iron plate and the inner tube of drum, and the tip of two insulating pads all is fixed with the conducting block that is connected with LED early warning screen, be equipped with a set of second spring jointly between the lower extreme of iron plate and the drum.

Preferably, mend hoist mechanism temporarily and connect in the fixed disk of hoist cable upside including fixed cover, the fixed a plurality of steel strands that are equipped with of lower extreme of fixed disk, each the lower extreme of steel strand all is fixed with the hoop, the terminal surface of stiffening beam is fixed with the hollow ring that cup joints with the hoist cable, the fixed grafting of terminal surface of hollow ring has a plurality of strong electromagnets that inhale.

Preferably, each tensile trigger mechanism all includes the fixed cover and locates the insulating ring of hoist cable lateral wall, the outer rampart an organic whole of insulating ring is provided with a plurality of insulating archs, each the slide has all been seted up to insulating bellied tip, and the inside slip of slide is equipped with the steel ball, the heating chamber that is linked together with the slide is seted up to the inside of insulating ring, and the inside fixed absorption magnetic path that is equipped with and each steel ball corresponds in heating chamber, each the bottom of slide is fixed with pressure switch, the inside in heating chamber is equipped with electric heat pole and the thermistor of establishing ties each other, thermistor is connected with the strong electromagnet and the early warning lamp of inhaling of homonymy.

Preferably, the exhaust pipe is fixedly inserted at a position, above the iron plate, of the side wall of each cylinder, the pressure valve is arranged inside the exhaust pipe, and the limiting electromagnet connected with the two conductive blocks is fixed at the bottom of each cylinder.

Preferably, the lower end of the iron ring is fixedly provided with a first clamping sleeve, the upper end of the hollow ring is fixedly provided with a second clamping sleeve matched with the first clamping sleeve, two flexible sealing sleeves are jointly arranged between the first clamping sleeve and the second clamping sleeve, and magnetorheological fluid is filled between the two flexible sealing sleeves.

A use method for the cable force monitoring and early warning device for the cable structure bridge comprises the following steps:

s1, when a bridge main body is prefabricated, pre-burying an empty box provided with a copper ring at a set position of the bridge main body, erecting a support plate between two main towers, and then installing a cylinder at the set position;

s2, when the sling is installed, welding two insulating rings, an iron ring and a fixed disc with a set position on the sling in advance, installing a steel strand between the fixed disc and the iron ring, then installing a hollow ring and an early warning lamp at the set position on a stiffening beam, and finally installing an LED early warning screen at the set position of a main tower;

s3, sequentially connecting the cables of all the parts according to a set route;

s4, when the bridge vibrates frequently, the two LED early warning screens display early warning characters to early warn vehicles and pedestrians entering the suspension bridge, and send early warning information to corresponding management departments of the suspension bridge;

and S5, after the suspension bridge is recovered to be stable from vibration, discharging professionals from corresponding departments to check whether each early warning lamp is turned on or not, wherein the turned-on early warning lamps indicate that the suspension bridge needs to be stressed excessively, and at the moment, the suspension bridge is required to be maintained by personnel, and the suspension bridge can normally pass after maintenance is finished.

Compared with the prior art, the cable force monitoring and early warning device and method for the cable structure bridge have the advantages that:

1. through the backup pad that sets up, empty box, the copper ring, the plastic case, the drum, neodymium iron boron magnet, first spring, the mutually supporting of buffering trigger mechanism and LED early warning screen, it is great that the amplitude takes place at the bridge main part, when the higher vibration of frequency, the copper ring that leads to through the vibration is at the lift removal of neodymium iron boron magnet department, can utilize the magnetic field reaction of copper to neodymium iron boron magnet, produce the ampere force opposite with neodymium iron boron magnet under lorentn magnetic force effect, utilize reverse thrust on the one hand, promote neodymium iron boron magnet and move down and increase the inside atmospheric pressure of drum, when utilizing frequent vibration and vibrating substantially, the action that atmospheric pressure can't in time reduce, can trigger LED early warning screen and carry out traffic early warning work, and reach and monitor early warning effect to the hoist cable, on the other hand, can utilize the resistance of opposite action, to a certain extent cushions the bridge main part.

2. Through the tensile trigger mechanism who is equipped with, can be based on under too big and self flexible effect of hoist cable amplitude, by permanent tensile back, when the bridge main part resumes calmly, can trigger the work of warning light to reach the monitoring warning action of the excessive atress of hoist cable.

3. Through the temporary hoisting compensation mechanism, the strong electromagnet can be automatically triggered to perform strong electromagnet attraction according to the stretching trigger mechanism, the strong electromagnet attraction iron ring is utilized, a steel strand and a fixed disc are matched, the temporary auxiliary that the sling subjected to excessive stress suspends the stress on the bridge main body can be realized, and the flexible compensation is performed on the sling, so that the maintenance time of the sling can be given to workers, and the safety of a suspension bridge after the sling is damaged is improved.

Drawings

FIG. 1 is a schematic structural diagram of a cable force monitoring and early warning device and method for a cable structure bridge provided by the invention;

FIG. 2 is a schematic structural diagram of a side-view connection between a sling and a main cable of the cable structure bridge cable force monitoring and early warning device and method provided by the invention;

FIG. 3 is a schematic structural diagram of a buffering trigger mechanism of the cable force monitoring and early warning device and method for a cable structure bridge provided by the invention;

FIG. 4 is a schematic structural diagram of a temporary hoisting mechanism of the cable force monitoring and early warning device and method for a cable structure bridge provided by the invention;

fig. 5 is a schematic structural diagram of a stretching trigger mechanism of the cable force monitoring and early warning device and method for a cable structure bridge provided by the invention.

In the figure: 1. a bridge main body; 2. a main tower; 3. a main cable; 4. a sling; 5. a stiffening beam; 6. a support plate; 7. empty boxes; 8. a copper ring; 9. a cylinder; 10. a plastic case; 11. a neodymium iron boron magnet; 12. a first spring; 13. a buffer trigger mechanism; 131. an elastic air bag; 132. an air inlet pipe; 133. an air outlet pipe; 134. an iron plate; 135. a rubber leather sheath; 136. slowly releasing air holes; 137. an insulating pad; 138. a conductive block; 139. a second spring; 14. an LED early warning screen; 15. a temporary supplementary hoisting mechanism; 151. fixing the disc; 152. steel strand wires; 153. an iron ring; 154. a hollow ring; 155. a strong attraction electromagnet; 16. a tension trigger mechanism; 161. an insulating ring; 162. an insulating protrusion; 163. a slideway; 164. steel balls; 165. an adsorption magnetic block; 166. a pressure switch; 167. a heating cavity; 168. an electric heating rod; 169. a thermistor; 17. an early warning light; 18. an exhaust pipe; 19. a limiting electromagnet; 20. a first ferrule; 21. a second ferrule; 22. a flexible sealing sleeve; 23. magnetorheological fluid.

Detailed Description

The following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

As shown in fig. 1-5, a cable structure bridge cable force monitoring and early warning device and method includes a bridge main body 1, two main towers 2, a main cable 3, a plurality of slings 4 and a stiffening beam 5, the main cable 3 is arranged on the tops of the two main towers 2 in an arc suspension arrangement, the stiffening beam 5 is arranged on the bridge main body 1, and the stiffening beam 5 is connected with the main cable 3 through a plurality of slings 4, wherein the number of the main cable 3 and the stiffening beam 5 is two, the number of the slings 4 is set according to the bridge span and design, and all the cable clamps connected between the main cable 3 and the slings 4, the anchors connected between the main cable 3 and the main towers 2 and other components are the existing mature technologies, and thus, redundant description is not given.

A supporting plate 6 is fixedly arranged between the two main towers 2 and below the bridge main body 1, a plurality of empty boxes 7 corresponding to the slings 4 are embedded in the bridge main body 1, a copper ring 8 is fixedly arranged in each empty box 7, a plurality of cylinders 9 are fixed on the supporting plate 6, a plastic box 10 is fixed on the end surface of each cylinder 9, a neodymium iron boron magnet 11 is movably arranged in each plastic box 10, a group of first springs 12 are arranged between the bottom of the neodymium iron boron magnet 11 and the plastic box 10, each plastic box 10 and the cylinder 9 on the same side are provided with a buffering trigger mechanism 13, the side walls of the two main towers 2 are provided with LED early warning screens 14 matched with the buffering trigger mechanisms 13, each buffering trigger mechanism 13 comprises an elastic air bag 131 arranged between the neodymium iron boron magnet 11 and the plastic box 10, an air inlet pipe 132 and an air outlet pipe 133 are inserted into the side walls of the elastic air bags 131 and the plastic boxes 10, the air inlet pipe 132 and the air outlet pipe 133 are both provided with a one-way valve, the cylinder 9 is communicated with the air outlet pipe 133, the inside of the cylinder 9 is movably provided with an iron plate 134, the side wall of the iron plate 134 is sleeved with a rubber leather sleeve 135 which is in interference fit with the inner wall of the cylinder 9, the side wall of the cylinder 9 at the upper side of the iron plate 134 is provided with a slow-release vent 136, the lower end of the iron plate 134 and the bottom of the inner cylinder of the cylinder 9 are both fixedly provided with an insulating pad 137, the end parts of the two insulating pads 137 are both fixedly provided with a conductive block 138 which is connected with the LED early warning screen 14, a group of second springs 139 are jointly arranged between the lower end of the iron plate 134 and the cylinder 9, when the bridge main body 1 normally works, gas generated when the NdFeB magnet 11 moves downwards can be discharged from the slow-release vent 136, and only when the bridge main body 1 vibrates frequently and with large amplitude, the slow-release vent 136 can not discharge air in time, at this time, the iron plate 134 drives the rubber leather sheath 135 to move down gradually until the conductive block 138 contacts, and then the LED early warning screen 14 can be triggered to perform early warning work on vehicles and pedestrians ready to enter the bridge main body 1.

The exhaust pipes 18 are fixedly inserted in positions, located above the iron plates 134, of the side walls of the cylinders 9, pressure valves are arranged inside the exhaust pipes 18, the limiting electromagnets 19 connected with the two conductive blocks 138 are fixed at the bottoms of the cylinders 9, the exhaust pipes 18 can discharge redundant air after the conductive blocks 138 are contacted, and accordingly the elastic air bags 131 are prevented from bursting, the limiting electromagnets 19 can be used for conducting power-on work after the conductive blocks 138 are contacted, magnetic attraction force generated at the moment can be larger than resilience force of the second springs 139 under the effect of air pressure inside the cylinders 9, the situation that the conductive blocks 138 are not contacted stably enough under the effect of the resilience force of the second springs 139 after a part of pressure is discharged through the slow-release air holes 136 is prevented, and only after the air pressure is restored to a normal level, the iron plates 134 can be reset under the effect of the second springs 139 at the moment, and early warning stability is guaranteed.

Each sling 4 is provided with a temporary hoisting compensation mechanism 15 connected with the bridge body 1, each temporary hoisting compensation mechanism 15 comprises a fixed disc 151 fixedly sleeved on the upper side of the sling 4, the lower end of the fixed disc 151 is fixedly provided with a plurality of steel strands 152, the lower end of each steel strand 152 is fixedly provided with an iron ring 153, the end face of the stiffening beam 5 is fixedly provided with a hollow ring 154 sleeved with the sling 4, the end face of the hollow ring 154 is fixedly inserted with a plurality of strong-absorption electromagnets 155, after the sling 4 is excessively stretched, the sling 4 cannot recover to a preset length under the self flexible action of the sling 4, at the moment, after the bridge body 1 recovers stably, the sling 4 cannot effectively bear the load at the position, so that the strong-absorption electromagnets 155 can work, the mutual attraction between the strong-absorption electromagnets 155 and the iron rings 153 is utilized, the temporary sling is carried out by matching the loads at the positions of the fixed disc 151 and the steel strands 152, and the maintenance time of personnel for maintaining the sling 4 is provided.

The lower end of the iron ring 153 is fixedly provided with a first clamping sleeve 20, the upper end of the hollow ring 154 is fixedly provided with a second clamping sleeve 21 matched with the first clamping sleeve 20, two flexible sealing sleeves 22 are jointly arranged between the first clamping sleeve 20 and the second clamping sleeve 21, magnetorheological fluid 23 is filled between the two flexible sealing sleeves 22, under normal conditions, the magnetorheological fluid 23 and the flexible sealing sleeves 22 cannot stress the steel strand 152 due to good flowability and flexibility, the normal sling 4 bearing load cannot be influenced, and only under the action of a strong magnetic field generated by the triggering work of the strong electromagnet 155, the magnetorheological fluid 23 is converted from a liquid state to a solid state under the action of the strong magnetic field, so that the first clamping sleeve 20 and the second clamping sleeve 21 can be matched to assist the stress strength between the iron ring 153 and the hollow ring 154, and the temporary hoisting effect is improved.

When the bridge body 1 vibrates, even if the suspension cable 4 is bent or vibrates by force to cause the steel ball 164 to be separated from the magnetic block 168, when the magnetic block 166 is triggered by mistake, the magnetic block 168 and the electromagnet 17 are connected in series, the temperature of the suspension cable 168 and the electromagnet 17 cannot be reduced by mistake, and even if the temperature of the suspension cable 165 is lowered, the temperature of the suspension cable 165 cannot be reduced by mistake, the temperature of the suspension cable 165 can not be reduced by the temperature of the electromagnet 165, so that the temperature of the suspension cable 165 cannot be reduced by the electromagnet 155, and the suspension cable 165 can be heated by mistake, and the temperature of the suspension cable 165 can be reduced by the electromagnet 165, so that the temperature of the suspension cable 165 is lowered, and the electric heating lamps 16 are arranged on the same side of the suspension cable, and the electromagnet 165 are arranged on the same side of the suspension cable, and the electric heating lamps 16 are arranged on the same side of the suspension cable, and the suspension cable 165 are arranged on the same side of the suspension cable, so that the suspension cable 165 cannot be heated by mistake, after the electric heating rod 168 is triggered and heated, the attraction of the adsorption magnetic block 165 to the steel ball 164 can be reduced, so that the unstable triggering of the pressure switch 166 caused by the micro-vibration of the sling 4 can be avoided, and the triggering stability of each strong-attraction electromagnet 155 is improved.

The use method of the cable force monitoring and early warning device for the cable structure bridge comprises the following steps:

s1, when a bridge main body 1 is prefabricated, pre-burying an empty box 7 provided with a copper ring 8 at a set position of the bridge main body 1, erecting a support plate 6 between two main towers 2, and then installing a cylinder 9 at the set position, wherein a plastic box 10 on the cylinder 9 and internal components of the cylinder 9 and the plastic box 10 are assembled in advance;

s2, when a sling 4 is installed, welding two insulating rings 161, an iron ring 153 and a fixed plate 151 with a set position on the sling 4 in advance in sequence, installing a steel strand 152 between the fixed plate 151 and the iron ring 153, then installing a hollow ring 154 and an early warning lamp 17 on the set position on a stiffening beam 5, and finally installing an LED early warning screen 14 at the set position of a main tower 2, wherein the LED early warning screen 14 can display special early warning characters when working through a conductive block 138, and a line between the LED early warning screen 14 and the conductive block 138 is also provided with an early warning signal transmitter (not shown in the figure) in series for wirelessly transmitting to a corresponding management department of the suspension bridge, so that early warning is required to be carried out on the management department while vehicles and pedestrians are early warned on site;

s4, when the bridge vibrates frequently, the two LED early warning screens 14 display early warning characters to early warn vehicles and pedestrians on the suspension bridge to enter, and send early warning information to corresponding management departments of the suspension bridge;

and S5, after the suspension bridge is restored to be stable from vibration, discharging professionals from corresponding departments to check whether each early warning lamp 17 is lightened, wherein if the warning lamps are lightened, the situation that the suspension cable 4 is excessively stressed needs to be shown, and at the moment, the persons need to be arranged to carry out overhaul and maintenance, and can normally pass after the maintenance is finished.

The operating principle of the present invention is now described as follows: after the components are installed, when the bridge main body 1 vibrates, the bridge main body 1 can drive the copper ring 8 to move, so that the position of the copper ring 8 relative to the neodymium iron boron magnet 11 on the same side can be changed, when the copper ring 8 moves downwards, electrons and copper ions in the copper ring 8 are under the action of the magnetic field of the neodymium iron boron magnet 11, the electrons in the copper ring 8 directionally move under the action of the lorentn magnetic force to generate current, and then generate an ampere force opposite to the neodymium iron boron magnet 11, under the action of an opposite repulsive force, the neodymium iron boron magnet 11 can move downwards and extrude the elastic air bag 131 and the first spring 12, air in the elastic air bag 131 is discharged out of the cylinder 9 from the air outlet pipe 133, after the bridge main body 1 drives the copper ring 8 to move upwards again, at the moment, the repulsive force disappears, the neodymium iron boron magnet 11 moves upwards to reset under the action of the first spring 12, at the moment, external air is replenished into the elastic air bag 131 through the air inlet pipe 132 again, air entering the cylinder 9 is slowly released from the slow release air holes 136, the air entering the cylinder 9 cannot be discharged from the slow release air holes 136 in time along with the increase of the vibration amplitude and the increase of the vibration frequency, the iron plate 134 is pushed to move downwards along with the increase of the air pressure in cooperation with the rubber leather sleeve 135 until the two conductive blocks 138 are contacted, the LED early warning screen 14 can work, early warning prompts are carried out on people ready to enter the bridge, and vehicles and people are prohibited from entering the bridge;

and as the vibration amplitude of the bridge body 1 increases, when the sling 4 is subjected to excessive vibration tension, under the action of the flexibility of the sling 4, after the sling 4 is restored to be stable in the bridge body 1, the sling 4 cannot restore itself, because the sling 4 is excessively stretched, after the bridge body 1 is restored to be stable, under the action of the bridge body 1 and the main cable 3, the whole stretched sling 4 can be in a bending state, and the bending amplitude of the central point of the sling 4 is the maximum, so that the insulating ring 161 can be inclined at a certain angle, at this time, as the insulating ring 161 is inclined, under the action of gravity, the steel balls 164 at the inclined side are separated from the magnetic attraction of the corresponding adsorption magnetic block 165 and slide to the bottom of the slide rail 163, so that the same-side pressure switch 166 can be extruded, at this time, the electric heating rod 168 and the thermistor 169 at the same side can be electrified to work, as the electric heating rod 168 works to heat up, the temperature of the thermistor 169 rises, the corresponding resistance value becomes lower, so that the corresponding strong-adsorption electromagnet 155 and the precaution electromagnet 17 can be electrified to work, at this time, the strong-attraction electromagnet 155 and the warning electromagnet 153 can be matched with the temporary suspension magnet 151 to detect whether the damage of the sling 4, and the temporary suspension electromagnet 151 can be observed by the temporary electromagnet, and the temporary electromagnet 151, and the temporary suspension electromagnet can be carried out.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. The utility model provides a cable structure bridge cable power monitoring early warning device, includes bridge main part (1), two main towers (2), main push-towing rope (3), a plurality of hoist cable (4) and stiffening beam (5), its characterized in that, main push-towing rope (3) set up and are the arc in the top of two main towers (2) and suspend the setting in midair, stiffening beam (5) set up on bridge main part (1), and stiffening beam (5) are connected with main push-towing rope (3) through a plurality of hoist cable (4) jointly, two lie in bridge main part (1) below and fix jointly and be equipped with backup pad (6) between main tower (2), the inside of bridge main part (1) is buried underground and is had a plurality of empty box (7) corresponding with hoist cable (4), and the inside of each empty box (7) all fixes and be equipped with copper ring (8), be fixed with a plurality of drums (9) in backup pad (6), each the terminal surface of drum (9) all is fixed with plastic box (10), and the inside of each plastic box (10) all is equipped with neodymium iron boron magnet (11) and the activity of each plastic box (10) is equipped with neodymium iron boron magnet (11) and buffering mechanism (10) jointly set up and all set up in neodymium iron boron magnet (10) and all set up in the homonymy including the equal homonymy of the inside of neodymium iron boron magnet (10) between the neodymium iron boron plastic box (10) and buffer mechanism (13) and all trigger each plastic box (13) and all the neodymium iron boron plastic mechanism (13) and all set up in each plastic box (13) and all trigger the homonymy (13) and all set up in neodymium iron boron plastic box (13) between each plastic box (13) and each neodymium iron boron plastic mechanism (10), each plastic box (13) and each neodymium iron boron plastic mechanism (13) and each plastic mechanism (13), each neodymium iron boron plastic box (13) and all trigger each neodymium iron boron plastic mechanism (13) and each plastic box (13) and all The side wall of the elastic air bag (131) and the side wall of the plastic box (10) are jointly inserted with an air inlet pipe (132) and an air outlet pipe (133), the air inlet pipe (132) and the air outlet pipe (133) are internally provided with a one-way valve, the cylinder (9) is communicated with the air outlet pipe (133), an iron plate (134) is movably arranged inside the cylinder (9), the side wall of the iron plate (134) is sleeved with a rubber leather sleeve (135) in interference fit with the inner wall of the cylinder (9), the side wall of the cylinder (9) is positioned at the upper side of the iron plate (134) and is provided with a slow-release air vent (136), the lower end of the iron plate (134) and the inner cylinder bottom of the cylinder (9) are fixedly provided with insulating pads (137), the end parts of the two insulating pads (137) are respectively fixedly provided with a conductive block (138) connected with the LED early warning screen (14), a group of second springs (139) is jointly arranged between the lower end of the iron plate (134) and the cylinder (9), the side walls of the two main towers (2) are respectively provided with a plurality of buffering triggering mechanisms (13), temporary suspension ropes (15) which are matched with temporary suspension wire (15), and temporary suspension wire (15) are arranged on the same side wall of each bridge lifting mechanism, the side wall of the stiffening beam (5) is inserted with a plurality of early warning lamps (17) connected with the stretching trigger mechanism (16).

2. The cable force monitoring and early warning device for the cable structure bridge according to claim 1, wherein the temporary hoisting mechanism (15) comprises a fixed disc (151) fixedly sleeved on the upper side of the sling (4), the lower end of the fixed disc (151) is fixedly provided with a plurality of steel strands (152), the lower end of each steel strand (152) is fixedly provided with an iron ring (153), the end surface of the stiffening beam (5) is fixedly provided with a hollow ring (154) sleeved with the sling (4), and the end surface of the hollow ring (154) is fixedly inserted with a plurality of strong-absorption electromagnets (155).

3. The cable structure bridge cable force monitoring and early warning device as claimed in claim 1, wherein each stretching trigger mechanism (16) comprises an insulating ring (161) fixedly sleeved on the side wall of the sling (4), a plurality of insulating protrusions (162) are integrally arranged on the outer annular wall of the insulating ring (161), a slide rail (163) is arranged at the end of each insulating protrusion (162), steel balls (164) are arranged in the slide rail (163) in a sliding manner, a heating cavity (167) communicated with the slide rail (163) is arranged in the insulating ring (161), an adsorption magnetic block (165) corresponding to each steel ball (164) is fixedly arranged in the heating cavity (167), a pressure switch (166) is fixed at the bottom of each slide rail (163), an electric heating rod (168) and a thermistor (169) which are connected in series are arranged in the heating cavity (167), and the thermistor (169) is connected with a strong adsorption electromagnet (155) and an early warning lamp (17) on the same side.

4. The cable structure bridge cable force monitoring and early warning device as claimed in claim 1, wherein an exhaust pipe (18) is fixedly inserted in a position, located above the iron plate (134), of the side wall of each cylinder (9), a pressure valve is arranged inside the exhaust pipe (18), and a limiting electromagnet (19) connected with the two conductive blocks (138) is fixed at the bottom of each cylinder (9).

5. The cable force monitoring and early warning device for the cable structure bridge according to claim 2, wherein a first clamping sleeve (20) is fixedly arranged at the lower end of the iron ring (153), a second clamping sleeve (21) matched with the first clamping sleeve (20) is fixedly arranged at the upper end of the hollow ring (154), two flexible sealing sleeves (22) are jointly arranged between the first clamping sleeve (20) and the second clamping sleeve (21), and magnetorheological fluid (23) is filled between the two flexible sealing sleeves (22).

6. The use method of the cable force monitoring and early warning device for the cable structure bridge of claim 1 is characterized by comprising the following steps:

s1, when a bridge main body (1) is prefabricated, pre-burying an empty box (7) provided with a copper ring (8) at a set position of the bridge main body (1), erecting a support plate (6) between two main towers (2), and then installing a cylinder (9) at the set position;

s2, when the sling 4 is installed, welding two insulating rings 161, an iron ring 153 and a fixed disc 151 with a set position on the sling 4 in advance, installing a steel strand 152 between the fixed disc 151 and the iron ring 153, then installing a hollow ring 154 and an early warning lamp 17 on a stiffening beam 5 at the set position, and finally installing an LED early warning screen 14 at the set position of a main tower 2;

s4, when the bridge vibrates frequently, the two LED early warning screens (14) display early warning characters to early warn vehicles and pedestrians on the suspension bridge, and send early warning information to corresponding management departments of the suspension bridge;

s5, after the suspension bridge is recovered to be stable from vibration, the corresponding department discharges professionals to check whether each early warning lamp (17) is lightened, if the early warning lamps are lightened, the situation that the stress of the suspension cable (4) is excessive is indicated, at the moment, the personnel are required to carry out maintenance, and normal passing can be carried out after the maintenance is finished.