摘要
以现场实测轮轨力为样本,利用参数假设检验方法,确定轮轨力幅值和频率特征,进而根据轮轨力分布特征编制荷载谱。建立轨道结构的多跨连续梁模型,分析群载作用下钢轨受力情况,确定最大弯曲应力所在位置;利用子模型技术,取最大弯曲应力所处的一跨钢轨为研究对象,建立子模型,分析不同幅值下轮轨接触斑内局部应力情况。根据临界平面法思想,建立随机轮轨力作用下钢轨滚动接触疲劳裂纹萌生寿命预测模型。结合具体实例分析表明:在一定速度范围内,轮轨力符合正态分布;根据随机轮轨力作用下钢轨滚动接触疲劳裂纹萌生寿命预测模型,预测U75V钢轨通过约560万吨总重时轨面萌生裂纹,与现场观察结果吻合。
The distribution of wheel-rail forces was obtained by analyzing the sample data from full-scale field tests.A load spectrum was established on the basis of the distribution of wheel-rail forces.Then two finite element models were established.One was the multi-spanned continuous beams model to analyze the global track responses and to determine the location of the largest bending stress.The other was the submodel by using the submodel technique;the submodel was used to study the local stress-strain field characteristics at the location of the largest bending stress under different amplitudes of wheel-rail forces.In the finite element model,the material model utilised was the nonlinear isotropic and kinematic hardening model.On the basis of the critical plane concept,a new prediction model was proposed to consider the effects of random wheel-rail forces and acting frequenies on the rolling contact fatigue（RCF） crack initiation life.The results show the distribution of wheel-rail forces follows normal distribution under a range of train speeds and the predication result from the model shows that rail heads would initiate head checks under 5.6 million gross tonne for U75V rails.The prediction result is in good agreement with the observation in flied.
出处
《铁道学报》
EI
CAS
CSCD
北大核心
2010年第3期66-70,共5页
Journal of the China Railway Society
关键词
钢轨
萌生寿命
随机轮轨力
临界平面
rail
crack initiation life
random wheel-rail force
critical plane
