This paper proposes a three-dimensional fully-coupled numerical model intended for the simulation of the dynamic behavior of ballasted railway tracks under real excitation. It is employed to reproduce the response of a French site located at the high-speed line connecting the two regions Bretagne and Pays de la Loire. The equation of motion is solved in the time domain by means of the finite difference method in which the rails and sleepers are represented by rectilinear beam elements which are rigidly attached to a spatial grid composed of rectangular cuboids. An adaptive meshing scheme based on the creation of load-attached moving nodes is adopted to model the moving train loads which are supposed to be time-independent. To validate the numerical simulations, a measuring campaign is performed in which tow aligned deflectometers are used to measure the displacement of the railway foundation just below the ballast layer under the track centerline. The velocity range of the high-speed passenger trains is covered in which four cases are taken into consideration ranging from 162 to 342 km/h. An excellent agreement between measurements and predictions is found. Therefore, the presented model can be considered reliable for the design of new high-speed lines.

本文提出了一个三维全耦合数值模型，旨在模拟压载铁路轨道在真实激励下的动态行为。它用于重现位于连接两个城市不列塔尼和卢瓦尔河地区的高速线上的法国站点的响应。通过有限差分法在时域中求解运动方程，其中轨道和轨枕由直线梁单元表示，直线梁单元牢固地连接到由矩形长方体组成的空间网格上。采用基于创建附有负载的移动节点的自适应网格划分方案来对假定与时间无关的移动列车负载进行建模。为了验证数值模拟，进行测量活动，其中使用两个对准的偏转仪测量轨道中心线下方压载层下方铁路基础的位移。涵盖了高速旅客列车的速度范围，其中考虑了四种情况，范围从162至342 km / h。发现测量值和预测值之间有很好的一致性。因此，对于新的高速线路设计，可以认为提出的模型是可靠的。