中小运量跨座式单轨车体疲劳寿命预测

Fatigue Life Prediction of Small and Medium Volume Straddle-Type Monorail Vehicle Body

针对中小运量跨座式单轨车辆头车车体受到循环动态载荷作用时在局部应力集中部位产生损伤并逐步积累,最终导致裂纹或者断裂的疲劳失效现象,通过有限元理论与疲劳分析理论结合对车体进行了疲劳寿命预测。分别将Simpack仿真分析获取的载荷时间历程和试验获取的载荷时间历程作为车体疲劳激励,选用修正后的车体构件S-N曲线,利用nCodeDesign-Life对车体进行了疲劳寿命预测。基于仿真载荷时间历程和基于试验载荷时间历程的疲劳寿命分别为68.19、71.58a,两种疲劳寿命分析结果均大于使用寿命年限30a。

When head body of small and medium volume straddle-type monorail vehicle is subjected to cyclic dynamic load,it will cause damage and accumulate gradually at local stress concentration area,eventually leading to crack or phenomenon of fatigue failure.Aiming at this phenomenon,the fatigue life of the body was predicted by combining finite element theory with fatigue analysis theory.The load time history obtained by Simpack simulation analysis and the load time history obtained by test were used as the vehicle body fatigue excitation respectively.The modified S-N curve of the car body components was selected,and the fatigue life prediction of the car body was made by nCode Design-Life.The fatigue life based on the simulation load time history and the test load time history was 68.19 and 71.58 years respectively.Two kinds of fatigue life analysis results were larger than the service life of 30 years.