中文摘要：

针对双块式无砟轨道枕边裂纹，采用ANSYS计算软件，建立流固耦合三维模型，在列车荷载和水耦合作用下，对双块式无砟轨道枕边裂纹内部动水压力和水流速度的分布和变化规律进行模拟计算，为双块式无砟轨道枕边裂纹的防治和维修提供理论基础。研究结果表明：裂纹内水压力最大值发生在裂纹中部尖端处，而最大水流速度发生在裂纹中部出口处；最大水压力和最大水流速度随着荷载幅值和频率的增加而增加，且荷载频率对水压力和水流速度的影响较大；随着裂纹开口量的增加，最大水压力和最大水流速度反而减小，但裂纹深度越深，最大水压力越大，且最大水流速度随着裂纹深度的增加最后成线性增加趋势。因此，裂纹深度是影响枕边裂纹水压力和水流速度的一个关键因素。

英文摘要：

In view of the crack beside the double block sleepers of double block ballastless track, the three - di- mensional model of fluid - solid coupling was established by virtue of the ANSYS software. Then the dynamic hydraulic pressure and the water velocity inside the crack beside the double block sleepers were simulated and calculated under the coupling action of train load and water, which can provide some theoretical basis for the prevention and maintenance of the crack. The results show that： The maximum hydraulic pressure inside the crack occurs at the crack tip which is in the central part of crack, but the maximum water velocity inside the crack oc- curs at the crack exit which is in the central part of crack; the maximum hydraulic pressure and the maximum water velocity increase with the increase of load amplitude and load frequency respectively, and the load frequen- cy has a larger effect on them; the maximum hydraulic pressure and the maximum water velocity decrease with the increase of the crack opening, but the deeper the crack depth is, the bigger the hydraulic pressure is, and the maximum water velocity increases linearly with the increase of the crack depth in the latter stage. Therefore, the crack depth is a fatal factor on the hydraulic pressure and water velocity.