2013 Fiscal Year Final Research Report

Study on reduction of the wind load and the aerodynamics vibration of the bridge girder by the bridge appendages

Research Project

Project/Area Number	24760368
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Structural engineering/Earthquake engineering/Maintenance management engineering
Research Institution	Kanto Gakuin University
Principal Investigator	NAKATO Seiji 関東学院大学, 理工学部, 准教授 (90339789)
Project Period (FY)	2012-04-01 – 2014-03-31
Keywords	相関長さ / 矩形断面柱 / 変動揚力係数 / ストローハル成分 / コヒーレンス
Research Abstract	Study on reduction of the wind loads and the aerodynamics vibrations of bridge girder by appendages with spanwise inhomogeneous section was conducted using wind tunnel. The appendages with spanwise inhomogeneous section were effective on reduction of fluctuating lift acting on the models with some side ratio. For the models with other side ratio, openings with spanwise inhomogeneous section were effective. Spectral analysis of the hot-wire data was conducted for evaluation of spanwise correlation length. Coherence values at vortex shedding frequency were plotted as function of distance. It could be represented well by Gaussian function, and correlation length was derived as integral scale. Evaluation method of windward correlation length was also proposed with employing auto-correlation function.