焦柳线石门段U71Mn50kg/m钢轨核伤扩展寿命的估计  

The evaluation of corewound expanding lifespan of U71Mn 50 kg/m rails on the Shimen district in Jiaoliu line

作　　者：周小林[1] 向延念[1] 

机构地区：[1]中南大学土木建筑学院,湖南长沙410075

出　　处：《中南大学学报（自然科学版）》2004年第3期495-499,共5页Journal of Central South University:Science and Technology

摘　　要：根据焦柳线石门段U71Mn50kg/m钢轨的运营状况,在室内利用三点弯曲试验测定了该钢轨的裂纹扩展速率曲线即a N曲线,经过回归分析,得出了该钢轨疲劳裂纹扩展速率的材料系数C=3.8771×10-12,m=3.6343;根据Paris公式对该钢轨在产生可探测的核伤(核伤直径不小于10mm)后由核伤扩展控制(核伤面积占轨头面积的30%)的使用寿命进行估计,确定该钢轨在2002a的运营条件下的使用寿命为所通过的总运量不超过46.8Mt,营运时间不超过421d,为管理部门对线路的养护、维修提供了依据。According to the transport conditions of U71Mn 50 kg/m rails on Shimen district in (Jiaoliu line, )the a-N curve of the rails is determined by three-point experiment in laboratory. The material coefficients of fatigue crack propagation speed ratio of the rails is obtained by the regression analysis, that is C=3.877 1×10^(-12) and m=3.634 3. According to the Paris formula, the lifespan controlled by core wound expanding is evaluated after the detective corewound occures in the rails, under the transport conditions in 2002. The results show that the total transport volume is not more than 46.8 Mt and the transport time is not more than 421 d, which provides the base for the maintenance of the railway line in the worksite.

关 键 词：钢轨伤损 核伤 使用寿命 裂纹扩展速率 

分 类 号：U213.42[交通运输工程—道路与铁道工程]