Influence mechanism of stabilizer height on vortex induced vibrationperformance of side girder cable stayed bridge with deck conveyor
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2022年2期
- Page:
- 56-67
- Research Field:
- 桥梁与隧道工程
- Publishing date:
Info
- Title:
- Influence mechanism of stabilizer height on vortex induced vibrationperformance of side girder cable stayed bridge with deck conveyor
- Author(s):
- LI Chunguang; MAO Yu; YAN Hubin; HAN Yan; ZHOU Xuhui
- School of Civil Engineering, Changsha University of Science & Technology, Changsha 410114, Hunan, China
- Keywords:
- bridge engineering; vortex induced vibration; wind tunnel test; downward vertical central stabilizers; mechanism of vortex induced vibration reduction
- PACS:
- -
- DOI:
- -
- Abstract:
- In order to study the influence of the central stabilizer plate at the bottom of the beam on the vortex induce vibration performance of the side main beam bridge with conveyor installed on the bridge deck, the vibration performance and pressure time history data of the side main beam under the action of the lower central stabilizer plate were obtained, through the wind tunnel vibration measurement and pressure test of the section model. Then the mean value, mean square deviation, power spectrum and the correlation between local and overall aerodynamic forces of the fluctuating pressure coefficient of the main beam under the action of three kinds of stable plates with different heights were comprehensively compared and analyzed. The results show that the stabilizing plate has a good effect on improving the aerodynamic stability of the side main beam section. The effect of the central stabilizer plate on the vibration response of the girder is basically the same when the height is 1 m and 1.5 m, which reduces the peak response by about 25%, while the central stabilizer plate can completely suppress the vibration response of the girder, when it extends out of the bottom of the girder by 0.5 m （the lower central stabilizer plate is 2 m high）. The analysis of pressure measurement data reveals that the main causes of vortex induced vibration are the strong pressure pulsation in the separation and reattachment area at the front of the upper surface, the strong correlation between the front aerodynamic force and the overall aerodynamic force at the lower surface, and the strong pressure pulsation with obvious correlation at the rear. The effect of adding lower central stabilizer of 1 and 1.5 m has little influence on the surface flow field distribution, but the pressure fluctuation of most areas of the upper and lower surfaces gradually decreases with the increase of the height of the stabilizer, and the vibration response of the main girder is weakened. The correlation of the rear area of the stabilizer plate on the lower surface decreases and its fluctuating pressure increases, which result in the same vortex vibration response of the main beam under the action of two highly stable plates. When 2 m high lower central stabilizing plate is added on the main beam, the vortex shedding frequency of some measuring points at the rear of the stabilizer is still concentrated in the vertical bending frequency of the model, but the energy is low. The correlation between the upper and lower surfaces and the overall aerodynamic force is destroyed in varying degrees, the pressure fluctuation is greatly weakened, and the vortex induced vibration is completely suppressed. 1 tab, 14 figs, 27 refs.
Last Update: 2022-04-13