Cable force testing method based on support stiffness of unknown damper under complicated boundary condition

A technology of boundary conditions and testing methods, which is applied to rubber shock absorbers, frequency method to measure cable force, and cable force testing based on unknown shock absorber support stiffness. Conservation and other issues, to achieve the effect of fast speed, improved efficiency, and improved accuracy of cable force calculation

CN109060219AActive Publication Date: 2018-12-21广东华交科工程科技有限公司
6 Cites 6 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2018-12-21

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention discloses a cable force testing method based on the support stiffness of an unknown damper under a complicated boundary condition. A technical problem that the cable force-frequency relationships of the inhaul cables change greatly because of installation of various dampers at end portions of inhaul cables of the modern bridges and thus the precision of cable force measurement by theconventional frequency method is affected can be solved. According to the invention, a finite-element cable force testing method for damper identification is provided for the inhaul cable with a damper. An inhaul cable is established and the position of a rubber ring of the damper is replaced by a spring device equivalently; a cable force frequency relationship under support stiffness of different dampers is obtained; the support stiffness of the inhaul cable is identified by using multi-order practically measured frequency and the cable force-frequency relationship is corrected; and then onthe basis of an interpolation principle, a practically measured cable force is determined by the practically measured frequency. When the cable force testing method is applied to a certain arch bridge, the finite-element-method-based cable force-frequency relationships before and after installation of the dampers at the end portions of the cable are close to the field practically measured results,so that the certain engineering value is verified.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to the technical field of cable force testing, in particular to a cable force test method based on unknown shock absorber support stiffness under complex boundary conditions, and to a cable force measurement method using a frequency method for a cable or suspender with a shock absorber at the end. Especially for the built-in rubber shock absorbers of both ends of the casing. Background technique

[0002] The cables under external loads and natural conditions will inevitably vibrate, and the vibrations will cause repeated flexures at the roots of the cables, accelerate the fatigue of the steel wires, and cause people to panic about the safety of the bridge structure. For this reason domestic and foreign cable companies or manufacturers have produced multiple shock absorbers to suppress the large-scale vibration of the cable. The analysis method for cables with shock absorbers is too complicated and has low practical applicability....

Examples

Embodiment

[0045] This embodiment is mainly based on the finite element software ANSYS to establish a heterogeneous cable, identify the support stiffness of the vibration damping device, and correct the cable force measurement method after the frequency relationship of the cable force. The specific steps are as follows:

[0046] R1. After the cable has been installed with a vibration damping device, measure the first three-order frequency f of the vibration of a cable1 1 , f 1 2 , f 1 3 ;

[0047] R2. Assuming that the damping device is simplified as an elastic support, calculate the cable force-frequency relationship of the pull cables with different support stiffnesses;

[0048] R3. Use formula (3) to calculate the residual sum of squares of the measured first three order frequencies obtained in step R2 and the theoretical first three orders under each support stiffness.

[0049] R4. According to the calculation result of step R3, find the support stiffness of the damping device c...