Fatigue Life Prediction of the Metro Bolster Beam under Complex Operating Conditions

U270.32%TH114; Sixteen operating conditions were determined by thestandards JIS-7105 and JIS-7106.The strength under complexoperating conditions was calculated with HyperWorks and thestrength analysis confirmed eight dangerous points of the metrobolster bean.Since the metro did not consider the impact of trafficlights and sudden road conditions,the load spectra at eightdangerous points were established by counting the running time,passenger flow,site layout,site quantity and turning situations.Thefatigue life of the metro bolster beam was projected by the von Misesstress method and the critical plane method.The results of these twomethods revealed that the maximum damage occurred at thedangerous point 7,and the fatigue life based on the critical planemethod was shorter than that based on the von Mises stress method.Since the McDiarmid model considered the effect of the magnitudeand direction of the normal stress and the amplitude of the shearstress,it is closer to the actual situations of the metro.Hence,theMcDiarmid model based on the critical plane method is morereasonable,and the method of fatigue life prediction is also suitableto the metro bolster beam of other lines.