跨座式轻轨钢轨道梁的动力特性有限元分析

Finite Element Analysis of Dynamic Behavior of Monorail Steel Track Beam of Straddle Type Light Rail Transit

为研究跨座式单轨交通钢轨道梁的动力特性，以重庆市袁家岗-谢家湾区间40．5m简支跨座式单轨交通钢轨道梁为研究对象，应用ANSYS的APDL语言，采用直接生成法建立有限元模型，分别计算模型的自振特性、静力和动力响应。动力分析的计算模型采用4辆车厢编组，车速为20～80km／h，分单线和双线加载。计算结果表明：该钢轨道梁基频较高，结构振型复杂，具有较高的整体刚度及强度，动力特性符合规范要求；平联及横梁对轨道梁的横向刚度和扭转刚度贡献较大；单线行车时轨道梁会产生扭转，使其上翼缘产生较大的横向位移。

To study the dynamic behavior of the monorail steel track beam of straddle type light rail transit; the 40.5-m span simply-supported monorail steel track beam in the section of the light rail transit from Yuanjiagang to Xiejiawan in Chongqing City was selected as the research object and the APDL language of the ANSYS was used to establish the finite element model by the direct generation method. The natural vibration characteristic, static load and dynamic load response of the model were respectively calculated. In the calculation model for dynamic analysis, a train composed of 4 wagons and with running speed of 20-80 km/h was used to apply load in steps to the single track and double tracks. The results of the calculation show that the base frequency of the steel track beam is rather high and the structural vibration modes are complicated. The track beam has high global rigidity and strength and the dynamic behavior of the beam can satisfy the requirements in the codes. The contribution of the lateral bracing system and cross beams to the lateral rigidity and torsional rigidity is great. The torsion will take place in the track beam in case the train travels on the single track and will cause considerable lateral displacement in the upper flange of the beam.