不同约束条件下中低速磁浮道岔主动梁自振特性

为了探究中低速磁浮道岔主动梁自振特性,以清远磁浮旅游线道岔系统为对象,建立3台车和2台车道岔主动梁的有限元模型,对安装面刚性约束和弹性约束下道岔主动梁进行有限元模态分析,与道岔主动梁自振特性实测结果进行对比,研究结果表明:安装面位移约束下3台车和2台车道岔梁的低阶模态频率显著大于实测值,弹性约束下道岔梁模态分析结果与实测结果接近,故中低速磁浮道岔梁有限元建模时应施加弹性约束;相较于2台车道岔梁方案,3台车道岔梁的垂弯模态频率有明显提高,但10~30 Hz频率内的横弯和扭转模态频率变化不大,仅仅增加中间台车抑制和减缓磁浮车岔15~20 Hz耦合共振的效果并不理想,提高道岔梁阻尼和加强道岔梁约束是更合理的选择。

Natural Vibration Characteristics of the Active Turnout Girder with Different Boundary Conditions for Low-medium Speed Maglev Transit

In order to explore the self-vibration characteristics of the active beam of Low-medium speed maglev turnout,finite element(FE)models of the active turnout girder supported by two movable trolleys or three movable trolleys are established with reference to the turnout system designed for the Qingyuan Maglev Tourist Line.Numerical mode analysis of the active turnout girder is carried out by applying the displacement constraints and the elastic boundary constraints on the FE model respectively and the calculated modal frequencies are compared with the test results.Research results show that the calculated low-order modal frequencies of the active turnout girder under the displacement constraints are significantly higher than the test results,but the calculation results of the active turnout girder under the elastic boundary are close to the test results,which implies that the FE modeling of the low-medium speed maglev turnout girder should use the elastic boundary constraints.Compared with the turnout girder with two trolleys,the vertical bending modal frequencies of the turnout girder with three trolleys are obviously greater,but the lateral and torsional modal frequencies in the 10~30 Hz frequency range do not change much,which indicates that adding a trolley on the middle of the active turnout girder with two trolleys cannot effectively suppress or reduce strong resonant response in the 15~20 Hz frequency range of maglev vehicle and turnout system,improving turnout damping and strengthening turnout constraint is a more reasonable choice.