无限元边界条件下有砟轨道的动力响应分析

为分析列车荷载作用下有砟轨道的动力响应,文章应用ABAQUS有限元软件建立三维路基基床有限元模型,采用无限元边界条件,分析了路基基床在静轮载5,7.5,10,12.5,15t五种情况下,速度分别为60,80,100km/h条件下的动力响应。有限元分析结果表明:(1)随着列车静轮载的增大,基床表层的竖向位移的幅值会逐渐变大,速度越大,静轮载的增加对竖向位移的增加影响越显著;(2)随着列车速度的增大,基床表层的竖向位移的幅值会逐渐变大,静轮载越大,速度的增加对竖向位移的增加影响越显著;(3)随着动荷载与选取点距离的缩短,选取点的竖向位移开始上下振动并逐渐增大,达到幅值后随着动荷载与选取点距离的增加,选取点的竖向位移逐渐恢复并有上下振动的现象。

In order to analyze the dynamic response of ballast track under train load,the finite element model of three-dimensional subgrade foundation bed is established by using ABAQUS finite element software.The finite element model of subgrade foundation bed under static wheel load of 5,7.5,10,12.5,15t is analyzed by using infinite element boundary condition.The dynamic responses are obtained at speeds of 60,80,100 km/h,respectively.The results of finite element analysis show that:(1)with the increase of the static wheel load of the train,the amplitude of the vertical displacement on the surface of the foundation bed will gradually increase,and the larger the speed,the more significant the increase of the static wheel load on the increase of the vertical displacement;(2)with the increase of train speed,The amplitude of the vertical displacement on the surface of the foundation bed will gradually increase,and the larger the static wheel load is,the more significant the increase of the velocity will have on the increase of the vertical displacement;(3)with the shortening of the distance between the dynamic load and the selected point,the vertical displacement of the selected point begins to vibrate up and down and gradually increases.After reaching the amplitude,with the increase of the distance between the dynamic load and the selected point,the vertical displacement of the selected point gradually recovers and has the phenomenon of up and down vibration.