The Fatigue Life Prediction and Analysis of RC Beams with HRBF500 Used in High-speed Rail

500 MPa level hot rolled steel bar of ultra-fine grains(HRBF500 steel bar)is successfully developed new-type steel of high-speed railways in Chinese metallurgical industry.HRBF500 steel bars will be used in high-speed reinforced,so it will be exposed to repeated loads.In view of that,the fatigue life predictions of RC beams reinforced with HRBF500'S are urgent to be solved.Based on ANSYS software,the fatigus life predictions of rectangular and T-section RC beams reinforced with HRBF500 were studied and compared well with the test results,which indicated that steel ratio,minimum fatigue load and load amplitude were the main factors affecting the fatiue life.In order to promote prediction method for practcal engineering design,the simplified fatigud life formulas were obtained based on comprehensive analysis of finite element calculation results.Those formulas can provide guidance for practical engineering design.