CAJ | 학술논문

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.
긴림철로교돈적매지관선,기피로수명수열차인기적진동적영향.문중이모매지천연기고압관선위례,건립관선순배내압화교돈진동재하연합작용하적관선피로수명평고방법.수선,편우안전고필,장측득적교돈상삼개방향진동재하직접시가우관선상,진행동응력계산,획득수시간변화적응력보;기차,운용우류계수법대응력수평화빈차진행분류;최후,운용재료S-N피로곡선화Miner선성루적손상원리대관선적피로수명진행평고,차분석불동토양역학성능삼수화교량진동빈차등인소대관선피로수명적영향,위매지관선적차류피로문제제공일개유효적공정분석방법.
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 pipeline and the stress spectrums of nodes with time were obtained. Second, the rain-flowing counting method was employed to sort the stress level and frequency. Finally, the S-N material fatigue curve and the Miner linear cumulative damnification principle were commonly applied to evaluate the fatigue lifetime of the pipeline, and effects of various mechanical parameters of soil as well as vibration frequency of bridge were analyzed, which provided an effective engineering analysis method for these kinds of fatigue problems of the buried pipeline.