摘要
采用智能轮对在京沪高铁开展时速为350 km/h的高速列车的车轴动应力试验,测试里程达90余万km,建立实际运行状态下车轴关键截面的应力谱,基于测试结果分析上下行线路、速度等因素对车轴应力谱的影响,并根据极值理论建立用于评价车轴超声探伤间隔的140万km台架试验谱,分别采用Paris公式与NASGRO方程预测140万km台架试验谱作用下卸荷槽区域裂纹扩展寿命,并通过车轴裂纹扩展台架试验进行验证。研究结果表明:高速列车动力车轴最大应力截面为卸荷槽根部截面,最大应力幅值为119 MPa;当车轴为导向轴时,其应力谱的应力极值与等效应力比作为非导向轴时增大约7%;随外推里程增加,车轴应力谱极值逐渐趋于稳定,140万km及1500万km外推应力谱的应力极值分别为121 MPa与127 MPa;初始深度为7.0 mm的半椭圆裂纹在台架试验140万km试验谱加载下扩展至7.5 mm,分别使用Paris公式与NASGRO方程进行数值分析时,裂纹深度由7.0 mm分别扩展至9.1 mm与7.7 mm,可知将Paris公式与NASGRO方程用于评估车轴剩余寿命时均具有保守性,NASGRO方程计算结果更接近试验值。
The dynamic stress test of 350 km/h high-speed train axle was carried out on Beijing—Shanghai railway line with the intelligent wheelset,and the test mileage reached more than 900000 km.The stress spectra were obtained for the key sections of the axle under the high-speed train running condition.Based on the test results,the influences of lines and speed on the axle stress spectra were analyzed.According to the extreme value theory,a bench test spectrum equivalent to 1.4 million kilometers was established to evaluate the ultrasonic detection interval of axle.Under the action of 1.4 million kilometers bench test spectrum,the crack propagation life of the axle was predicted by Paris formula and NASGRO equation,and the accuracy was verified by the bench test.The results show that the maximum stress section of the high-speed train power axle is the root section of the unloading groove,and the maximum stress amplitude is 119 MPa.When the axle is used as a guide axle,the stress extreme value and equivalent stress in the stress spectrum increase by about 7%compared with that of the nonguide axle.The extreme value of the axle stress spectrum tends to be stable with the increase of the extra polation mileage.The extreme stress values of 1.4 million kilometers and 15 million kilometers extrapolated stress spectra are 121 MPa and 127 MPa,respectively.The bench test shows the semi-elliptical crack with an initial depth of7.0 mm expands to 7.5 mm under the test spectrum load.When Paris formula and NASGRO equation are used for numerical analysis,the crack depth expands from 7.0 mm to 9.1 mm and 7.7 mm,respectively.It can be seen that both the Paris formula and NASGRO equation are conservative when they are used to evaluate the remaining life of the axle,and NASGRO equation is much more accurate.
作者
王文静
闫瑞国
丁然
张振先
沙淼
单巍
WANG Wenjing;YAN Ruiguo;DING Ran;ZHANG Zhenxian;SHA Miao;SHAN Wei(Key Laboratory of Vehicle Advanced Manufacturing,Measuring and Control Technology,Ministry of Education,Beijing Jiaotong University,Beijing 100044,China;CRRC Qingdao Sifang Co.Ltd.,Qingdao 266111,China;CRRC Changchun Railway Vehicles Co.Ltd.,Changchun 130062,China;China State Railway Group Co.Ltd.,Beijing 100844,China)
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2022年第5期1955-1964,共10页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(52075032)
中国国家铁路集团有限公司科技研究开发计划课题(P2020J024)
高速铁路系统试验国家工程实验室高速轮轨关系试验室开放合作创新基金资助项目(2021YJ269)。
关键词
高速列车
车轴动应力
台架试验谱
极值理论
裂纹扩展寿命
high speed train
axle dynamic stress
bench test spectrum
extreme value theory
crack propagation life
