Compared with the moving concentrated load model, it is more realistic and proper to use the moving distributed mass and load model to simulate the dynamics of a train moving along a railway track. In the problem of a moving concentrated load, there is only one critical velocity, which divides the load moving velocity into two categories: subcritical and supercritical. The locus of a concentrated load demarcates the space into two parts: the waves in these two domains are called the front and rear waves, respectively. In comparison, in the problem of moving distributed mass and load, there are two critical velocities, which results in three categories of the distributed mass moving velocity. Due to the presence of the distributed mass and load, the space is divided into three domains, in which three different waves exist. Much richer and different variation patterns of wave shapes arise in the problem of the moving distributed mass and load. The mechanisms responsible for these variation patterns are systematically studied. A semi-analytical solution to the steady-state is also obtained, which recovers that of the classical problem of a moving concentrated load when the length of the distributed mass and load approaches zero.

中文翻译：

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移动分布质量和载荷的黏弹性地基上无限大梁的稳态响应

与移动集中载荷模型相比，使用移动分布质量和载荷模型来模拟沿铁路轨道行驶的火车的动力学更为现实和恰当。在集中载荷运动问题中，只有一个临界速度，它将载荷运动速度分为两类：亚临界和超临界。集中载荷的位置将空间划分为两个部分：这两个域中的波分别称为前波和后波。相比之下，在移动分布质量和载荷的问题中，存在两个临界速度，这导致了分布质量移动速度的三类。由于存在分布的质量和载荷，因此将空间划分为三个域，其中存在三个不同的波。在移动的分布质量和载荷问题中，出现了许多更丰富和不同的波形变化形式。系统地研究了负责这些变化模式的机制。还获得了稳态的半解析解，当分散的质量和载荷的长度接近零时，它可以解决经典的移动集中载荷问题。