Analysis of Harmonic Vibration of Cable-Stayed Footbridge under the Influence of Changes of the Cables Tension

Abstract

The paper presents numerical analysis of harmonically excited vibration of a cable-stayed footbridge caused by a load function simulating crouching (squats) while changing the static tension in chosen cables. The intentional synchronized motion (e.g., squats) of a single person or group of persons on the footbridge with a frequency close to the natural frequency of the structure may lead to the resonant vibrations with large amplitudes. The appropriate tension changes in some cables cause detuning of resonance on account of stiffness changes of structures and hence detuning in the natural frequency that is close to the excitation frequency. The research was carried out on a 3D computer model of a real structure - a cable-stayed steel footbridge in Leśnica, a quarter of Wrocław, Poland, with the help of standard computer software based on FEM COSMOS/M System.

Analytical assessment of stay cable vibration mitigation using shape memory alloy wire

“…Steel cables are used for supporting bridge decks of cable-stayed bridges. These cables are subjected to oscillations due to vehicular and wind loads [1,2]. Cables have light damping therefore they are prone to windinduced high amplitude oscillations [3,4].…”

“…x t , is the transverse deflection of the cable, c is the viscous damping per unit length, x d is the damper position from the left end, ( ) F t , is the distributed load on the cable. The nonlinearity of the cable due to sag can be accounted by introducing a sag parameter,2 …”

Active vibration control of large space flexible slewing truss using cable actuator with input saturation

“…Cable structures have had their most spectacular applications in civil engineering, particularly in large cable‐stayed bridges . Cable structures have been used on a smaller scale in space applications.…”

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