为使轴箱体静强度与疲劳强度的有限元校核与分析结果更为合理可信,在建立计算模型时对轴箱拉杆进行了模拟。由于缺乏使用ANSYS超弹性单元必须的橡胶应力一应变试验数据,基于给定拉杆横向、纵向刚度和外载条件下的拉杆理论变形量,通过调整用于模拟橡胶垫和橡胶关节实体单元的材料泊松比与弹性模量,使相同外载下的计算变形量逐渐趋于理论值,实现了对拉杆的模拟。依照推演的EN13749标准,完成了对出口某国机车轴箱体的强度校核,其静强度与疲劳强度均能满足标准要求。对比简化拉杆连接的模型计算结果,可以看出合理的轴箱拉杆模拟,能使分析结果更为可信,尤其是在轴箱体拉杆安装座部位,避免了因过度简化可能导致的局部应力分布奇异,从而影响对真正应力较大部位和结构危险点的判断。
To make the results of finite element analysis on static and fatigue strength for axle-box body more reasonable and dependa- ble, the simulation of pull-rod was included during the establishment of computing model for axle-box body. Due to the lack of test stress-strain data of rubber, which is one of the essential conditions for utilizing the hyperelasticity element in ANSYS, present simula tion of axle-box pull-rod was realized through two steps. Firstly, the theoretical deformation according to the given lateral stiffness and longitudinal stiffness for pull-rod was calculated under specified load condition. Secondly, by adjusting Poisson's ratio and elastic modu- lus for solid elements which were applied to simulating the rubber pad and the rubber joint of axle-box pull-rod, the finite element calcu lating results could approach the theoretical deformation gradually. Based on the extrapolated standard EN 13749, strength analysis for the axle-box body of certain export locomotive was accomplished. Both the static and the fatigue strength met the standard require- ments. Comparison with the analysis results obtained from a pull-rod simplified computing model showed that, reasonable simulation of axle-box pull-rod could make the strength analysis results more credible. Especially when focusing on the pull rod mounting position of axle-box body, present simulation of pull-rod could avoid the stress singularity in local area, and thus avoid the misjudgments of the high stress positions and the critical points for structure.