Theory of rain–wind induced vibration of stay cables: Toward unsteady and fully coupled modeling

Abstract

Large-amplitude rain–wind induced vibration (RWIV) is a complex fluid–structure interaction process that may develop if light rainfall and moderate wind act concurrently on long stay cables of a cable-stayed bridge. However, its dynamic characteristics and excitation mechanism are remained an open question. Recently, a theoretical framework for the analysis of RWIV was proposed, based on a quasi-steady-state approximation of the movement of upper rivulet, to reveal the main features of the dynamic process of RWIV. In the present study, we further consider the unsteady and dynamic behaviors of the moving upper rivulet and its coupling effects with the cable movement. The periodic mass, circumferential movement of the upper rivulet was modeled based on experimental observations. The theoretical results are then validated by comparison with experimental results. In addition, some parameters that influence RWIV are investigated in detail. The augmented theory in the present study gives a more accurate model and promotes more reliable evaluations of the dynamic behaviors of RWIV of stay cables.