车轴裂纹扩展寿命的分析与计算方法  

Analysis and Calculation Method of Axle Crack Growth Life

作　　者：刘志明[1] 孙守光[1] 缪龙秀[1] 

机构地区：[1]北京交通大学轨道车辆结构可靠性与运用检测技术教育部工程研究中心,北京100044

出　　处：《中国铁道科学》2008年第3期89-94,共6页China Railway Science

基　　金：铁道部科技研究开发计划项目(2005J034)

摘　　要：在由加载条件试验得出车轴裂纹扩展规律的基础上,引入有效应力强度因子范围ΔKeff值,建立适用于各种加载条件的裂纹扩展规律模型;给出实际运用条件下初始裂纹尺寸、超偏载、轮轴压装配合导致应力集中等因素影响车轴裂纹扩展的理论分析方法;建立车轴裂纹扩展寿命的计算模型,并采用Romberg数值积分法和Newton-Rophson迭代法对车轴剩余寿命进行预测。运用本文给出的模型和计算方法,以RD轴轮座部为例,对不同运用工况、不同尺寸裂纹车轴的剩余寿命进行了计算分析;以某客车RC轴断轴事故为例,对车轴初始裂纹尺寸进行计算,验证了超限裂纹漏探是导致该车轴断裂的主要原因。Based on the experiment results of crack growth life of railway axle under the determinate loads, a crack growth model that can be used for all kinds of loads was formulated by introducing effective stress intensity factor range △Keff. The theoretical analysis method for crack growth calculation of axle was put forward by considering the effects of initial crack length, overload or unbalanced load, and especially the stress concentration caused by the forcing fit of the wheel set. A model for calculating the axle crack growth life was established and the residual life was predicted by using Romberg integral method and Newton-Rophson iterative method. Using the provided model and the calculation method in this paper, the residual life of RD axle＇s wheel seat was given based on different load cases and different initial crack lengths. And finally the initial crack length of RC axle in fracture of certain passenger car was obtained, which verified that the detection omission of ultralimit axle cracks is the major cause of axle failure.

关 键 词：车轴裂纹 变幅加载 裂纹扩展 扩展寿命计算 

分 类 号：U270.331[机械工程—车辆工程] U270.12[交通运输工程—载运工具运用工程]