Research On The Stay Cable Vibration And Vibration Reducing Equipment

With greater ability to go span obstacle, cable-stayed bridge is widely used in recent years. Cable-stayed bridge and stay cables are prone to vibrate under wind, rain, earthquake and vehicle loads. Sometimes vibration can lead to bridge accident. So it is important to search effective and reasonable method to reduce cable-stayed bridge vibration.According to finite element method principle, this paper adopts LINK10 unit and BEAM4 unit to simulate stay cable, beam and bridge tower in ANSYS. Establish a cable-stayed bridge model and analysis its dynamic characteristic. From above, obtain inherent frequency and corresponding model of cable-stayed bridge. The result proves that cable-stayed bridge vibrates easily and it shows three dimensions vibration properties.This paper analyses stay cable's construction and vibration forms. Compare the dynamic characteristic of single cylindrical pole stay cable with that of stay cables which are composed by four steel wires and seven steel wires. Compare the inherent frequency of stay cable obtained by analytic method and ANSYS software. The comparison result indicates that the most error is less than 10%. The result also indicates that we can use single cylindrical pole stay cable to simulate stay cable which is composed by a cluster of steel wires.By comparing several kinds of vibration reducing methods which are widely used on cable-stayed bridge, a vibration reducing equipment has been worked out. For different models of high damp rubber rings, four factors three level orthogonal experiment table is designed out to do much investigation on their dynamic characteristics. The paper simulates and compares vibration displacement of nodes on stay cable, the result indicates that the vibration reducing effect of vibration reducing equipment is obvious. Changing the installation positions of stay cable vibration reducing equipment, the result indicates that the higher installation position the better vibration reducing effect in certain scope.The paper uses finite element software to do research on the cable-stayed bridge, stay cable and vibration reducing equipment. Compare the result obtained by ANSYS calculation, practical measure and analytic calculation. The research result proves its correctness. The paper's research content and results have value of reference for dynamic analysis of cable-stayed bridge and designing of stay cable vibration reducing equipments.