A simplified analytical method for lateral dynamic responses of a transmission tower due to rockfall impact

Frontiers in Materials

Materials

Jianing Peng¹  Junhua Li¹  Songlin Qin¹  Xingsen Zhang¹  Meihua Bian² 

[1] Guangxi Key Laboratory of Intelligent Control and Maintenance of Power Equipment, Electric Power Research Institute of Guangxi Power Grid Co., Ltd., Nanning, China;[e-mail];

关键词: transmission tower;    rockfall impact;    fundamental frequency;    dynamic displacement response;    modal analysis;   

DOI  :  10.3389/fmats.2023.1229327

 received in 2023-05-26, accepted in 2023-07-12,  发布年份 2023

来源: Frontiers

【 摘 要 】

Transmission tower structures support high-voltage power lines that carry electricity over long distance and rockfall is one of critical disasters during its safe operation. This paper presented a simplified analytical methodology for lateral dynamic responses of a transmission tower structure due to rockfall impact. At first, the lateral dynamic displacement of a lattice transmission tower structure can be represented by a second-order partial differential equation and half sine wave was used for rockfall impact. Then, the solution can be approximated by a set of specified shape functions multiplied by time-dependent generalized coordinates. And the partial differential equation is discretized into a set of single degree of freedom system. And then the shape function can be determined by solved an eigenvalue function and the fundamental frequency of a transmission tower can was derived based on the energy method and combination synthesis method. Finally, the lateral dynamic displacements can be approximately obtained. A numerical study of a transmission tower was conducted. Parametric study of the effect of impact location height, impact duration, peak impact force, as well as the distribution of cross-arms on dynamic responses were also carried out. And the results show that the discrepancy between the analytical and the computed of fundamental frequency is less than 3%, the error of dynamic displacement is within 10%, and the fundamental frequency of the structure decreases with the increase of the tower top additional mass ratio.

【 授权许可】

Unknown   
Copyright © 2023 Bian, Peng, Qin, Zhang and Li.