摘要
以陇海铁路沿线某古遗址为研究对象，采用考虑轨道不平顺、附加动载、轨面波磨效应的列车荷载作为输入，结合有限元软件及外接VDLOAD子程序，建立了轨道、道床、地面、古遗址的三维有限元分析模型。通过进行白噪声激励发现，古遗址竖向振动响应明显，且其主要响应频率集中于16~50Hz之间；另外研究了以120km/h运行的列车诱发振动和多遇地震作用下古遗址内应力的分布规律。结果表明：在列车诱发振动荷载作用下，古遗址内最大应力主要分布于古遗址二层关楼墙角以及门洞拱券处等复合受力位置，易造成应力集中，所得应力分布位置与现场观测所见古遗址裂缝分布位置基本一致；古遗址裂缝的分布大体与列车运行方向垂直，随着列车诱发振动的频繁作用及列车车速不断提高，顺列车运行方向振动效应对关楼现存裂缝的影响将逐渐增强；多遇地震作用下关楼应力主要集中于现有裂缝处，一旦发生小震易造成关楼裂缝继续发展甚至发生坍塌。
Based on the ancient ruins next to the Longhai railway lines, the track irregularity, the additional dynamic load and the rail surface wave grinding effect are taken into account as the train loading, a three-dimensional finite element model which contains the rail, track bed, the ground and the ancient ruin is set up by the FEM software with the subroutine VDLOAD. The vertical vibration is obvious by the white noise excitation, and the main frequency response is between 16~50Hz. Meanwhile, the stress distribution of the ancient ruins caused by the train running at 120km/h and the small earthquake is studied also. Results obtained show that the place which the maximum stress distributes in the ancient ruins is the corner of the upper floor and the dome of the pass and also at the same locations the cracks initiate. Cracks in the ancient ruins nearly perpendicular to the direction of the train's movement and the crack influenced by the vibration along the train's movement. Moreover, the influence caused by the train would be increased with the increasing load and speed of the train. Meanwhile, the maximum stress caused by the frequent earthquake distributes in the place where the crack exists, on condition that the earthquake occurred, the ruin would be damaged or even collapse.
出处
《应用力学学报》
CAS
CSCD
北大核心
2014年第2期224-229,310,共6页
Chinese Journal of Applied Mechanics
基金
国家自然科学基金(51178126
51208125)
广州市科技计划项目(2013J2200074
11F102010004)
关键词
古遗址
振动
列车荷载
有限元分析
应力分布
ancient ruin,vibration,train load,finite element analysis,stress distribution.
