波动问题中桥梁转体结构等效动力计算模型

Equivalent Dynamic Calculation Model of Bridge Swivel Structure in Wave Problem

研究铁路环境振动在转体桥梁中传播的波动问题时,转体结构的模拟至关重要。精细化建模能够有效提高结果的准确性,但其建模过程较为复杂且求解需耗费大量计算时间。为了提高波动问题的求解效率,基于结构动力学中阻抗等效原则对转体结构复杂几何进行了简化,推导了等效计算公式,建立了等效的动力计算模型,通过将实测的加速度时程作为输入,求解结构振动响应,并结合精细化有限元模型和现场振动试验的结果验证其准确性。研究表明:本文所提出的等效动力计算模型可得到较为精准的响应结果,且求解时间仅为精细化有限元模型的29%。该模型具有建模简单、计算快速等优点,能够为研究转体桥梁波动问题提供一种新的建模思路。

The modelling of swivel structures is essential when studying the fluctuations in railway environmental vibrations propagating of swivel bridge.Refined modeling of the swivel structure can effectively improve the accuracy of the results,but the modeling process is too complex to compute efficiently.To improve the calculation efficiency of swivel structures,an equivalent dynamic calculation model was proposed based on the principle of impedance equivalence in structural dynamics.Next,the equivalent calculation formula was derived,and the equivalent dynamic calculation model was established.Finally,the structural vibration response was solved by taking the measured acceleration responses as input,and its accuracy was verified by comparing the refined finite element model and the results of field vibration tests.The results demonstrate that the above equivalent dynamic calculation model can obtain relatively accurate response results,and the solution time is only 29%of the refined finite element model.Thus,the proposed equivalent dynamic calculation model has the advantages of simple modeling and fast calculation,which can provide a new modeling method for studying the wave problem of swivel bridges.