基于基准有限元模型的箱梁TMD振动控制研究

针对高架桥梁结构引起的振动噪声问题,研究TMD控制箱梁结构振动的特性。为了获得精准的箱梁有限元模型,首先以铁路32 m简支箱梁桥为原型,按10:1的几何相似比设计制作简支箱梁缩尺试验模型,应用ANSYS软件建立初始动力有限元模型;对有限元模型模态分析与试验模型模态测试得到的自由模态信息进行误差分析,并采用基于灵敏度分析的模型修正技术对初始动力有限元模型弹性模量和密度进行修正,得到基准有限元模型,误差确认结果显示修正后的有限元模型更精准地反应箱梁的振动特性;进一步利用基准有限元模型,开展TMD控制简支箱梁桥振动的研究,研究结果表明TMD对于抑制桥梁竖向共振有很好的效果。

Research on TMD vibration control of box girder based on reference finite element model

Aiming at the problem of vibration and noise caused by the elevated bridge structure, the characteristics of the vibration control of the TMD were preliminarily studied. In order to obtain the accurate finite element model of box girder, the similarity model of the simple box-girder bridge with span of 32 m was designed and produced with geometry scale factor of 10 firstly, and the initial finite element model was established by ANSYS software. Error analysis of free modal information is obtained from modal analysis of finite element model and modal test of experimental model. The elastic modulus and density of the initial dynamic finite element model were revised using the model-correcting technique based on sensitivity analysis. Then the baseline finite element modal was acquired. The error confirmation results show that the modified finite element model can more accurately react the vibration characteristics of the box girder. Further, using the reference finite element model, the vibration of the TMD controlled simple box girder was studied. The research results show that TMD has a good effect on suppressing the vertical resonance of the bridge.