内压和振动载荷联合作用下埋地管线疲劳寿命评估

紧临铁路桥墩的埋地管线,其疲劳寿命受列车引起的振动的影响。文中以某埋地天然气高压管线为例,建立管线循环内压和桥墩振动载荷联合作用下的管线疲劳寿命评估方法。首先,偏于安全考虑,将测得的桥墩上三个方向振动载荷直接施加于管线上,进行动应力计算,获得随时间变化的应力谱;其次,运用雨流计数法对应力水平和频次进行分类;最后,运用材料S—N疲劳曲线和Miner线性累积损伤原理对管线的疲劳寿命进行评估,且分析不同土壤力学性能参数和桥梁振动频次等因素对管线疲劳寿命的影响,为埋地管线的此类疲劳问题提供一个有效的工程分析方法。

FATIGUE LIFETIME EVALUATION OF BURIED PIPELING UNDER INTERNAL PRESSURE AND VIBRATING LOADS

The fatigue lifetime of the buried pipelines is greatly affected by the loads arising from the train vibrating in the case that they are close to the railway pier. An evaluation method of fatigue lifetime under cyclic internal pressure of pipeline and vibrating loads of pier is established for some natural gas high pressure pipeline. First,from the conservative point of view,dynamic stress calculations were conducted by directly exerting the measured vibration loads of pier in three directions on the pipeli...