【摘要】 采用空间非线性动力有限元理论和准静态荷载法,以多雨地区铁路隧道易出现翻浆冒泥等病害现象的轨下铺底结构为研究对象,建立了铁路隧道铺底结构的动载计算模型。对列车振动冲击荷载作用下隧道铺底混凝土结构四种计算工况的动力响应进行了数值模拟,并与模型试验测试结果进行比较分析,得出了主要结论:隧道铺底结构的使用寿命是由铺底材料的抗弯强度控制;竖向应力动力系数随深度的增加逐渐衰减;衰减系数随铺底底面的深度增加而减小,同种工况中随速度的增加而减小。这些研究结果为深入了解列车动载对隧道基底结构破坏的影响程度,较彻底地解决隧道基底破损所产生的病害问题提供了参考。更多还原

【Abstract】 Based on the eight nodes non-linear dynamic finite element theory and quasi-static load method, taking bedding structure of railway tunnel as a research objective, a dynamic load calculating model is established. Dynamic responses under four kinds of calculating operational conditions of tunnel bedding structure are analyzed in consideration of the influence of train vibration and shock loads, the relationship between the vertical dynamic load stress and the train velocity is studied, and the influence of the structure load status in different bedding load circumstances is analyzed. In order to compare with the numerical simulation results, a model in the proportion of 1∶1is made and corresponding dynamic load test is operated. Some conclusions are obtained as follows: dynamic coefficient of vertical stress attenuates as the bed depth increases; vertical stress increases linearly with the increase of train velocity, while increasing rate relates to structure stiffness and bed depth; attenuation coefficient decreases as the depth increases, and also as the velocity increases in the same operational condition.更多还原