底座板脱空对板式无砟轨道行车动力特性的影响

采用有限元动力学软件ANSYS/LS-DYNA,建立了底座板脱空条件下车辆-轨道-路基垂向耦合振动模型,以分析底座板脱空对车辆和轨道系统动力性能的影响.计算结果表明:当底座板下纵向脱空长度小于3.125 m(脱空面积10 m2)时,对车辆及轨道系统动力响应的影响较小;当底座板下纵向脱空长度超过3.125 m时,钢轨垂向位移、转向架及车体垂向加速度显著增大,可能危及行车舒适性和安全性,因此建议底座板下纵向脱空长度限值不超过3.125 m. 

Effects of Contact Loss underneath Concrete Roadbed on Dynamic Performances of Slab Track-Subgrade System

ANSYS/LS-DYNA, a large general finite element software, was used to establish a vertical vibration model for vehicle-track-subgrade coupling system, and the dynamic responses of a vehicle-track system caused by contact loss underneath concrete roadbed were analyzed. The research results show that contact loss length less than 3.125 m (corresponding to a contact loss area of 10 m2) has a negligible effect on the dynamic responses of a vehicle-track system. The dynamic responses of the vertical displacement of rail and vertical accelerations of bogie and car body will increase significantly when the contact loss is longer than 3.125 m, being unfavorable to the ride comfort and safety, so contact loss length underneath concrete roadbed should be less than 3.125 m.