Investigation on wind-induced vibration of stay-cables based on field measurements of large-scale cable model and wind tunnel tests

点击翻译按钮获取中文摘要

In this study, to clarify the mechanisms of high-speed vortex induced vibration, rain-wind induced vibration and galloping for the stay-cables, the field observations using large-scale inclined cable models and wind tunnel tests were conducted. From the field observation tests, the following results were obtained.・The vibrations which seems to be the rain-wind induced vibration were observed under raining condition.・The galloping type vibrations with the first out plane mode were observed when a typhoon passed the site. Generally, the galloping must be reduced under high turbulent flow. Therefore, the further research will be needed. However, there might be a possibility of galloping on the real stay-cables.Also, the results from the wind tunnel tests were as follows.・The upper water rivulet on the cable surface due to the rain fall and the wind turbulence have important rolls on the high-speed vortex induced vibration.・Frequency variation of Karman vortex sheddings along the cable axis might induce the high-speed vortex induced vibration. Also, the position of upper water rivulet must be an important factor. Furthermore, there are two kinds of Karman vortex frequencies exist, if the position of artificial water rivulet on the cable model surface varies, and then, the reduced wind velocity, using the frequency as the difference of these two frequencies, coincides with the reduced wind velocity for high-speed vortex induced vibration.・To evaluate the inclined effects on the static force for inclined cable, the splitter plate was installed in the wake of circular cylinder with artificial water rivulet, and then, the static forces for inclined cables with water rivulet can be measured and seems to be rather reasonable.・Using the upper results, high-speed vortex induced vibration including rain-wind induced vibration is rather hard to explain by the quasi-steady theorem.