不同轨道梁模型对磁悬浮车/桥垂向耦合动力响应的影响探讨

磁悬浮铁路大量采用了封闭式高架桥。目前国内的磁悬浮车 /桥动力响应研究的模型中 ,轨道梁大多假设为梁单元。笔者将分别建立梁单元和板壳元的轨道梁模型 ,通过自编车 /桥垂向耦合程序 ,探讨这两种模型在不同车速和轨道状态下对磁悬浮车辆 /桥垂向耦合动力响应的影响。笔者得出在一定车速以下梁单元轨道梁模型梁跨中挠度将稍小于板壳元轨道梁模型的梁跨中挠度 ,而车体加速度相差不大 ,说明轨道梁假设为梁单元是简单合理的 ;不同轨道状态时 ,板壳元轨道梁模型和梁单元轨道梁模型的梁跨中挠度相差不很大 ,但车体垂向加速度相差较大 ,因此 ,在不同轨道状态下轨道梁模型的选取对磁悬浮车辆 /桥动力响应的影响较大。这些研究将对磁悬浮高架线路设计和磁悬浮列车安全运行具有一定的理论指导意义。

Discussion on the Influence of Different Elevated-beam Guideway Models on Maglev Vehicle/Elevated-beam Guideway Vertical Coupling Dynamic Response

Closed elevated guideway is widely applied in maglev railway system. At present in the maglev vehicle/elevated-beam guideway dynamic model in China, elevated-beam guideway is mostly supposed to be the beam element. Guideway's beam element and shell element bridge models are established respectively. By self-edited vehicle/bridge vertical coupling program, the influence of these two models on maglev vehicle/ elevated-beam guideway vertical coupling dynamic response under different vehicle velocity and state of track is discussed. The result shows that under certain vehicle velocity the deflection of guideway mid-span of beam element guideway model is a little smaller than that of shell element guideway model and the vehicle vertical accelerations of the two models are almost the same. These demonstrate that the supposition of beam element guideway model is simple and reasonable. Under different track state the discrepancy of the deflection of guideway mid-span between beam element guideway model and shell element guideway model is not obvious, but the discrepancy of the vehicle vertical accelerations is rather obvious. So under different track state the choice of guideway model would distinctively affect the maglev vehicle/elevated-beam guideway vertical coupling dynamic response. These studies would provide theoretical guidance for optimizing the guideway design and the safe operation of the maglev vehicle.