摘要
为了分析列车通过钢轨焊接接头时产生的轮轨动态冲击力对钢轨焊接接头表面裂纹扩展特性的影响,首先采用车辆-轨道耦合动力学数值模型计算轮轨垂向力,并建立带表面裂纹的轮轨接触有限元模型;然后将轮轨垂向力结果加载到有限元模型中分析其对裂纹扩展特性的影响。结果表明:在轮轨动态相互作用下,钢轨焊接接头处表面斜裂纹的扩展以剪切模式为主导,裂纹应力强度因子KI和应力强度因子范围ΔKII随着列车速度的增大而增大;裂纹长度和裂纹面摩擦系数对应力强度因子范围ΔKII影响较大,当裂纹长度从3mm增加到10mm时,其ΔKII增大了204.2%,当裂纹面摩擦系数从0.1增加到0.6时,其ΔKII减小了153.4%。
Influence of wheel/rail dynamic impact forces generated at rail welds on rail surface crack propagation characteristics is investigated.Firstly,wheel/rail vertical force using the established vehicle-track coupling dynamic model is calculated,and then the finite element model of wheel/rail contact with surface crack is established.Finally,the wheel/rail vertical force is loaded in the finite element model and analyzes the influence of it on rail surface crack propagation characteristics.Results obtained show that,under the wheel/rail dynamic interaction,the mode of shear dominates the inclined surface crack propagation.The stress intensity factor K I and the range of stress intensity factor ΔK II of crack increase with an increasing of train speed.Crack length and friction coefficient between crack surfaces affect ΔK II significantly,ΔK II raises 204.2% with crack length increasing from 3mm to 10mm,and it decrease 153.4% with the friction coefficient between crack surfaces increasing from 0.1 to 0.6.
出处
《应用力学学报》
CAS
CSCD
北大核心
2013年第4期624-629,653,共6页
Chinese Journal of Applied Mechanics
基金
国家自然科学基金委员会和铁道部高速铁路基础研究联合基金(U1134202)
国家科技支撑计划(2009BAG12A01)
长江学者和创新团队发展计划
中央高校基本科研业务费专项资金(SWJTU11CX140)
