Experimental verification of the effectiveness of elastic cross-ties in suppressing wake-induced vibrations of staggered stay cables

• Published in: Engineering structures Vol. 167; pp. 151 - 165
• Main Authors: He, Xuhui, Cai, Chang, Wang, Zijian, Jing, Haiquan, Qin, Chengwen
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15.07.2018; Elsevier BV
• Subjects: Amplitudes; Cables; Cross-ties; Staggered stay cables; Stay cable vibration; Stiffness; Vibration; Vibration control; Vibrations; Wake induced vibration; Wind induced vibration; Wind speed; Wind tunnel testing; Wind tunnels; Wind induced vibration; Vibration control; Wake induced vibration; Stay cable vibration; Staggered stay cables; Cross-ties
• ISSN: 0141-0296; 1873-7323
• DOI: 10.1016/j.engstruct.2018.04.033

•Wake induced vibration (WIV) was reproduced using flexible models in a wind tunnel.•Vibration frequency of downwind cables increase with increasing wind speed.•Elastic cross-tie reduced the WIV amplitude by 74%.•Cross-tie changed first mode dominating WIV into multi-modes chaotic vibration.•Scale ratio of cross-tie stiffness is derived for practical application. In the present study, two pairs of cable models were specially designed and tested to reproduce wake induced vibration (WIV) of stay cables in a wind tunnel. The interaction between multi-modes and the flexibility of the stay cables were considered. The downwind cables experienced large vibrations beyond a critical wind speed, similar to classical galloping. The response characteristics in terms of vibration amplitude, frequency, and trajectory were investigated in detail. The observed tendency of the increase in vibration frequency with increasing wind speed is adequately consistent with the previous studies. Finally, elastic cross-ties were vertically installed and connected two neighboring cable models in an attempt to suppress WIV. The wind tunnel tests demonstrated that the elastic cross-tie modified the single-mode dominated WIV into a type of chaotic multi-mode vibration and successfully reduced the vibration amplitude by ∼74%. The reason why the elastic cross-tie suppressed RWIV was qualitatively discussed. The scale ratio of the cross-tie stiffness was derived for engineers. Consequently, for the first time, the elastic cross-tie was proposed and verified to be effective to suppress the WIV of stay cables.