流线型桥梁断面颤振稳定性数值模拟  

Numerical simulation for flutter stability of streamlined bridge decks

作　　者：白桦[1] 夏勇[1] 刘健新[1] 李加武[1] 

机构地区：[1]长安大学公路学院,陕西西安710064

出　　处：《长安大学学报（自然科学版）》2011年第3期45-50,共6页Journal of Chang’an University(Natural Science Edition)

基　　金：国家自然科学基金项目(50578014)

摘　　要：对于流线型桥梁断面颤振稳定性,采用动网格实现结构分状态强迫振动法,提取稳定的气动力,按照最小二乘法求得不同折减风速的颤振导数。研究了理想薄平板的8个颤振导数,并将数值计算结果与Theodorsen理论解进行对比,发现采用该方法识别颤振导数与理论解吻合得很好。采用该方法计算了3种不同流线型桥梁断面的颤振导数,并计算了颤振临界风速。结果表明:增大主梁的宽高比,可以提高主梁的颤振稳定性;宽高比相同时,主梁底板采用折线形状要比圆弧线颤振稳定性好。To study the flutter stability of streamlined bridge decks, the moving grid technique was adopted to simulate the forced vibration of the rigid body with different motion. The flutter derivatives with different reduced wind speed were extracted from obtained aerodynamic forces with least square method. The flutter derivatives of the ideal flat plate were computed and compared with the Theodorsen＇s theoretic solutions. The computed results agree well with Theodorsen＇s theoretic solutions. This method was used to calculate the flutter derivatives and critical wind speeds of three streamlined bridge decks. The results show that： increasing the aspect ratio can improve the flutter stability of the streamlined bridge deck; using the polygonal-line deck, the flutter stability is better than the one of arc line shape deck when their aspect ratio is same. 2 tabs, 6 figs, 11 refs.

关 键 词：桥梁工程 流线型断面 颤振稳定性 数值模拟 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]