Dynamic soil stress of a subgrade-culvert transition section from DK49+689. 0 toDK49+
700. 7 on theQinhuangdao-Shenyang passenger special linewasmeasured and its influencing factors,
including train speed, structural changes and soil depth, were analyzed. The results indicate that
dynamic earth pressure trends to rise with the increase of train speed. When train speed exceeds
220 km/h, dynamic earth pressure trends to be unchanged, but it is always bigger than the earth
pressure ofquasi-static state. In addition, dynamic earth pressure attenuates rapidlywith the increase
of soil depth, approaching to the quasi-static earth pressure. Furthermore, it is also related to the
structure of subgrade andmuch greater over the culvert than in normal subgrade.