基于2.5维有限元-边界元分析轨道随机不平顺影响下的铁路地基振动  

Railway ground vibration with track random irregularities based on 2.5D finite element-boundary element method

作　　者：冯青松[1] 雷晓燕[1] 

机构地区：[1]华东交通大学"铁路环境振动与噪声"教育部工程研究中心,南昌330013

出　　处：《振动与冲击》2013年第23期13-19,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金资助项目(51008123;U1134107);国际科技合作与交流专项(2010DFA82340);江西省青年科学家培养对象(20112BCB23015)

摘　　要：建立了完善的2.5维有限元-边界元耦合模型分析移动谐荷载作用下钢轨、扣件、轨枕、道砟、路基和地基等各部分的振动响应;利用既有的车辆-轨道-路基-地基耦合系统垂向振动解析模型得到轨道谐波高低不平顺引起的垂向动态轮轨力;在此基础上,结合轨道随机不平顺功率谱密度,提出了列车运行引起的地基振动功率谱计算方法。对比分析了地基表面测点垂向振动加速度级的理论计算与现场实测结果,证明了该模型的合理性。模型能有效地分析具有复杂横截面形状的轨道-路基-地基系统的振动响应以及多种轨道、地基减振隔振措施的影响,且具有较高的计算效率,适用于铁路线路设计阶段的方案比较研究。A perfect two and half dimensional( 2. 5D) finite element-boundary element coupling model was established to analyze vibration responses of rails,fasteners,sleepers,ballast,embankment and ground under moving harmonic loads. Vertical dynamic wheel-rail forces due to track vertical harmonic irregularities were gained by using the existing analytical model for vertical vibration of a vehicle-track-embankment-ground coupled system. On this basis,a computation method for power spectrum of ground vibration due to train's running was proposed by considering the power spectral densities of track random irregularities. The theoretical calculation results and the corresponding measured ones of vertical acceleration levels for ground surface points were compared,and the rationality of the proposed model was validated. It was shown that the proposed model can effectively analyze vibration responses of a track-embankment-ground system with complex cross-sectional shapes,and also can analyze influences of a variety of vibration reduction and vibration isolation measures; this model has a higher computation efficiency,and is applicable to comparing design schemes of railway lines.

关 键 词：2.5维有限元-边界元 轨道随机不平顺 车辆-轨道-路基-地基耦合系统 地基振动 功率谱 

分 类 号：U213.2[交通运输工程—道路与铁道工程]