Cable force intelligent measurement integrated device for short sling of suspension bridge

Abstract

The invention discloses a cable force intelligent measurement integrated device for a short sling of a suspension bridge, and belongs to the technical field of bridge cable force intelligent measurement. The cable force intelligent measurement integrated device comprises an upper end anchor cup and a lower end anchor cup which are oppositely arranged, the sling is connected between the upper end anchor cup and the lower end anchor cup, and one end, away from the sling, of the upper end anchor cup is connected with an upper end lug plate; the end, away from the sling, of the lower-end anchor cup is connected with a pull rod through a sleeve, a coaxial circle center hole is formed in the side, away from the lower-end anchor cup, of the pull rod, a measuring rod is arranged in the circle center hole, the two ends of the measuring rod and the circle center hole are in a locked state, and the measuring rod is implanted into a displacement sensor. According to the invention, factors such as short sling boundary conditions, great fundamental frequency identification difficulty and great flexural rigidity influence can be overcome, and the cable force can be accurately identified.

Description

Technical Field

[0001] The invention relates to an integrated intelligent cable force measurement device for short slings of a suspension bridge, belonging to the technical field of intelligent cable force measurement of bridges. Background Art

[0002] Suspension bridges are among the most powerful types of bridges. Cables are crucial load-transmitting components connecting the main girder and the main cables, transferring the load borne by the main girder to the cables. Changes in cable tension significantly impact the internal forces and linear changes of the suspension bridge structure. They are a key indicator for evaluating the condition of long-span suspension bridges and a crucial basis for analyzing the current stress state of the structure and assessing its health. Accurate identification of cable tension is crucial for evaluating the service condition of suspension bridges.

[0003] Relevant applied technologies have shown that the cable tension in long cables can be accurately identified using the frequency method. The accuracy of the frequency method depends primarily on the precision of the vibration pickup technology and the accuracy of the cable tension calculation formula (including the identification of various parameters). Hammer excitation can accurately identify the first two fundamental frequencies of short cables, but the interference caused by forced vibration in cables shorter than 5m is significant. This is especially difficult for bridges in operation, making it more difficult to detect their natural frequencies. The fundamental frequency resolution is low and the accuracy is poor. Conventional cable tension detection methods have difficulty accurately identifying the cable tension in short cables due to factors such as boundary conditions, the difficulty in identifying the fundamental frequency, and the significant influence of bending stiffness. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the existing technology and provide an integrated intelligent cable force measurement device for short cables of suspension bridges, which can overcome factors such as the boundary conditions of short cables, the difficulty in identifying the fundamental frequency and the great influence of bending stiffness, and accurately identify their cable forces.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] An integrated intelligent cable force measurement device for short suspension bridge cables, comprising an upper anchor cup and a lower anchor cup arranged relatively to each other, wherein the upper anchor cup and the lower anchor cup are connected to the cable, the end of the upper anchor cup away from the cable is connected to the upper ear plate, the end of the lower anchor cup away from the cable is connected to the pull rod via a sleeve, a coaxial center hole is provided on the side of the pull rod away from the lower anchor cup, a measuring rod is arranged in the center hole, the two ends of the measuring rod are in a locked state with the center hole, and the measuring rod is implanted in a displacement sensor.

[0007] A protective sleeve, a gasket, a washer and a nut are sequentially sleeved on the pull rod in a direction away from the lower end anchor cup.

[0008] The displacement sensor is located in the pull rod, and a slot for accommodating the displacement sensor is provided at the end of the pull rod at the position of the center hole.

[0009] The two ends of the measuring rod are clamped to the center hole by springs. The two springs are fixed on the measuring rod. A clamping groove for accommodating the springs is provided on the side wall of the center hole.

[0010] The upper end ear plate is fork-shaped, and a sling pin is installed on the upper end ear plate.

[0011] The measuring rod and the pull rod are made of the same material, and the center lines of the measuring rod and the pull rod coincide with each other.

[0012] Beneficial effects of the present invention: The present invention provides an integrated intelligent cable force measurement device for short slings of a suspension bridge. A coaxial center hole is provided on the side of the pull rod away from the lower end anchor cup, and a measuring rod is arranged in the center hole. The two ends of the measuring rod are locked with the center hole, and the measuring rod is implanted in the displacement sensor. Since the measuring rod and the pull rod are locked, the measuring rod and the pull rod are forced to maintain the same deformation. The measuring rod obtains the displacement change of the pull rod through the position sensor and calculates the axial force of the pull rod. Since the axial force of the pull rod is the same as the cable force of the sling, the cable force of the short sling is accurately measured, thereby solving the problem that the cable force of the short sling is difficult to accurately measure in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic cross-sectional structural diagram of an integrated intelligent cable force measurement device for short slings of a suspension bridge according to the present invention;

[0014] The reference numerals in the figure are as follows: 1-upper end ear plate; 2-sling pin; 3-upper end anchor cup; 4-sling; 5-steel strand; 6-sleeve; 7-pull rod; 8-washer; 9-nut; 10-measuring rod; 11-displacement sensor; 12-protective sleeve; 13-gasket. DETAILED DESCRIPTION

[0015] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0016] like Figure 1As shown, the present invention discloses an integrated intelligent cable force measurement device for short suspension bridge cables, comprising an upper anchor cup 3 and a lower anchor cup 5 disposed relative to each other, with a cable 4 connected between the upper anchor cup 3 and the lower anchor cup 5. The end of the upper anchor cup 3 away from the cable 4 is connected to the upper ear plate 1, and the end of the lower anchor cup 5 away from the cable 4 is connected to the pull rod 7 via a sleeve 6. The centerline of the cable coincides with the centerline of the pull rod 7, and the cable force of the cable 4 is the same as the axial force of the pull rod 7. The cable force is obtained by measuring the axial force of the pull rod 7. The cable 4 and the pull rod 7 must be effectively connected to ensure that the performance of the connection device is superior to that of the lower anchor cup 5 and the pull rod 7 and that it will not be damaged during service.

[0017] The present invention is designed to provide a measuring element, which includes a measuring rod and a displacement sensor. A coaxial center hole is provided on the side of the pull rod 7 away from the lower anchor cup 5. A measuring rod 10 is disposed within the center hole. The measuring rod 10 extends into the uniform stress region of the pull rod 7 and deforms in concert with the pull rod 7. The uniform stress region enables accurate measurement of the displacement change of the pull rod 7, and the length of the measuring rod 10 can be adjusted according to actual project needs. The two ends of the measuring rod 10 are locked with the center hole, and the measuring rod 10 is embedded in the displacement sensor 11. The displacement sensor 11 is replaceable and can be wired to transmit data.

[0018] The working principle of the present invention is: the measuring rod 10 and the pull rod 7 in the measuring element of the present invention are locked, forcing the measuring rod 10 and the pull rod 7 to maintain the same deformation. The measuring rod 10 obtains the displacement change of the pull rod 7 (the change in the distance between the two locking points) through the displacement sensor 11, and calculates the axial force of the pull rod 7. Since the axial force of the pull rod 7 is the same as the cable force of the sling, accurate measurement of the cable force of the short sling is achieved.

[0019] The specific method of using the present invention is as follows: first, the force measurement of the pull rod is calibrated. The displacement change measured by the displacement sensor under different calibration tensions is measured to find the corresponding relationship between the two. Then, during actual operation, the pull rod tension, that is, the suspension cable tension, is calculated based on the actual displacement change.

[0020] Example 2

[0021] like Figure 1 As shown, the present invention discloses an integrated intelligent cable force measurement device for short suspension bridge cables, comprising an upper anchor cup 3 and a lower anchor cup 5 arranged relatively to each other, with a cable 4 connected between the upper anchor cup 3 and the lower anchor cup 5. The end of the upper anchor cup 3 away from the cable 4 is connected to the upper ear plate 1, the upper ear plate 1 is fork-shaped, and a cable pin 2 is installed on the upper ear plate 1. The end of the lower anchor cup 5 away from the cable 4 is connected to the pull rod 7 through a sleeve 6. The center line of the cable coincides with the center line of the pull rod 7, the cable force of the cable 4 is the same as the axial force of the pull rod 7, and the cable force of the cable is obtained by measuring the axial force of the pull rod 7. The cable 4 and the pull rod 7 must be effectively connected to ensure that the performance of the connection device is better than that of the lower anchor cup 5 and the pull rod 7, and it will not be damaged during service.

[0022] The present invention is designed to provide a measuring element, which includes a measuring rod and a displacement sensor. A coaxial center hole is provided on the side of the pull rod 7 away from the lower anchor cup 5. The diameter of the center hole is 3-4 mm, and in this embodiment, the diameter of the center hole is 3.5 mm. A measuring rod 10 is provided in the center hole. The measuring rod 10 and the pull rod 7 are made of the same material, and the center line of the measuring rod 10 coincides with the center line of the pull rod 7. The measuring rod 10 penetrates into the stress uniformity area of ​​the pull rod 7 and deforms in accordance with the pull rod 7. The stress uniformity area can accurately measure the displacement change of the pull rod 7, and the length of the measuring rod 10 can be adjusted according to actual engineering needs. The two ends of the measuring rod 10 are locked with the center hole. Specifically, the two ends of the measuring rod 10 are locked with the center hole by springs. Two springs are fixed to the measuring rod 10, and a slot for accommodating the springs is provided on the side wall of the center hole. The measuring rod 10 is implanted in the displacement sensor 11. The displacement sensor 11 is located in the pull rod 7. The end of the pull rod 7 is located at the center hole and is provided with a slot for accommodating the displacement sensor 11. The displacement sensor 11 is replaceable and can be wired to transmit data.

[0023] A protective sleeve 12 , a gasket 13 , a washer 8 and a nut 9 are sequentially sleeved on the pull rod 7 in a direction away from the anchor cup 5 at the lower end, for tightening the pull rod 7 .

[0024] The working principle of the present invention is: the measuring rod 10 and the pull rod 7 in the measuring element of the present invention are locked, forcing the measuring rod 10 and the pull rod 7 to maintain the same deformation. The measuring rod 10 obtains the displacement change of the pull rod 7 (the change in the distance between the two locking points) through the displacement sensor 11, and calculates the axial force of the pull rod 7. Since the axial force of the pull rod 7 is the same as the cable force of the sling, accurate measurement of the cable force of the short sling is achieved.

[0025] The specific method of using the present invention is as follows: first, the force measurement of the pull rod is calibrated. The displacement change measured by the displacement sensor under different calibration tensions is measured to find the corresponding relationship between the two. Then, during actual operation, the pull rod tension, that is, the suspension cable tension, is calculated based on the actual displacement change.

[0026] The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An integrated intelligent cable force measurement device for short slings of suspension bridges, characterized by: The invention comprises an upper anchor cup (3) and a lower anchor cup (5) which are arranged opposite to each other, a sling (4) being connected between the upper anchor cup (3) and the lower anchor cup (5), an end of the upper anchor cup (3) away from the sling (4) being connected to an upper ear plate (1), an end of the lower anchor cup (5) away from the sling (4) being connected to a pull rod (7) via a sleeve (6), a coaxial center hole being provided on a side of the pull rod (7) away from the lower anchor cup (5), a measuring rod (10) being provided in the center hole, both ends of the measuring rod (10) being locked with the center hole, and the measuring rod (10) being implanted in a displacement sensor (11).

2. The integrated intelligent cable force measurement device for short slings of a suspension bridge according to claim 1 is characterized in that: The pull rod (7) is sequentially sleeved with a protective sleeve (12), a gasket (13), a washer (8) and a nut (9) in a direction away from the lower end anchor cup (5).

3. The integrated intelligent cable force measurement device for short slings of a suspension bridge according to claim 1 is characterized in that: The displacement sensor (11) is located in the pull rod (7), and a slot for accommodating the displacement sensor (11) is provided at the end of the pull rod (7) at the position of the center hole.

4. The integrated intelligent cable force measurement device for short slings of a suspension bridge according to claim 1 is characterized in that: The two ends of the measuring rod (10) are locked with the center hole by springs, the two springs are fixed on the measuring rod (10), and a slot for accommodating the springs is provided on the side wall of the center hole.

5. The integrated intelligent cable force measurement device for short slings of a suspension bridge according to claim 1 is characterized in that: The diameter of the central hole is 3-4 mm.

6. The integrated intelligent cable force measurement device for short slings of a suspension bridge according to claim 1 is characterized in that: The length of the measuring rod (10) is 15-40 cm.

7. The integrated intelligent cable force measurement device for short slings of a suspension bridge according to claim 1 is characterized in that: The upper end ear plate (1) is fork-shaped, and a sling pin shaft (2) is installed on the upper end ear plate (1).

8. The integrated intelligent cable force measurement device for short slings of a suspension bridge according to claim 5, characterized in that: The diameter of the central hole is 3.5 mm.

9. The integrated intelligent cable force measurement device for short slings of a suspension bridge according to claim 1, characterized in that: The measuring rod (10) and the pull rod (7) are made of the same material.

10. The integrated intelligent cable force measurement device for short slings of a suspension bridge according to claim 1, characterized in that: The measuring rod (10) coincides with the center line of the pull rod (7).

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