平列式公铁两用钢桁梁桥疲劳损伤及寿命研究
Fatigue Damage and Life of Steel Truss Joints in Parallel-Type Combined Highway and Railway Bridge
储胡照 1吉军立 1董婷婷 2王佐才 3孙晓彤 2丁福凡2
作者信息
- 1. 中铁上海设计院集团合肥有限公司 合肥,230011
- 2. 合肥工业大学土木与水利工程学院 合肥,230009
- 3. 合肥工业大学土木与水利工程学院 合肥,230009;安徽省基础设施安全检测与监测工程实验室 合肥,230009
- 折叠
摘要
为研究某平列式公铁两用钢桁梁桥车桥耦合振动引起的钢桁梁桥节点构件的疲劳损伤,建立了局部节点精细化的全桥有限元模型和车辆多刚体模型,采用Craig-Bampton法求解了车桥耦合振动系统方程.首先,利用动态称重系统采集同线路全年公路交通流数据,统计分析车辆的车型、车速、车重及车间距等参数分布特征;其次,结合列车荷载模型,基于S-N曲线及Miner线性累计损伤理论,计算获得钢桁梁节点由列车和汽车通行导致的节点疲劳损伤,并基于雨流计数法对其疲劳寿命进行了预测;最后,探讨了列车速度、载重、不平整度及腐蚀对钢桁梁节点的累积疲劳损伤及疲劳寿命的影响.结果表明:节点疲劳损伤随着速度增大不呈现单一变化,随着载重增大和不平整度变差迅速增大,疲劳寿命降低明显;考虑腐蚀造成的节点刚度折减时,节点累积疲劳损伤曲线的发展是非线性的,疲劳寿命降低显著.
Abstract
In order to study the fatigue damage of joints in a parallel-type combined highway and railway steel truss bridge,the bridge finite element model containing refined joints as well as the multi-body models of the train and the vehicle is established.The equation of motion for the vehicle-bridge coupled system is solved using Craig-Bampton method.The dynamic weighting system is used to collect annual highway traffic flow data,and the distribution characteristics of parameters,such as vehicle type,speed,vehicle weight and vehicle spacing,are statistically analyzed.Combining the train load model,the fatigue damage of steel truss joints due to the train and vehicle loads is calculated using S-N curve and Miner linear cumulative damage theory,and the fatigue life is predicted using the rain flow counting method.The effects of train speed,load and unevenness on the fatigue damage of steel truss joints are discussed and the development of cumulative fatigue damage and life of the steel truss joints under environmental corrosion is analyzed.The results indicate that the variation of fatigue damage does not show a monotonous trend with increasing train speed.The fatigue damage increases rapidly,and the fa-tigue life decreases significantly with load increasing or flatness deteriorating.Considering the reduction in the joint stiffness caused by environmental corrosion,the development of cumulative fatigue damage curve is nonlin-ear,and the fatigue life decreases significantly.
关键词
公铁两用桥梁/疲劳损伤/疲劳寿命/钢桁梁节点/车桥耦合Key words
highway and railway bridge/fatigue damage/fatigue life/steel truss joint/vehicle-bridge cou-pling/corrosion引用本文复制引用
基金项目
国家自然科学基金优秀青年科学基金资助项目(51922036)
出版年
2024
NETL
NSTL
万方数据