基于超弹性本构参数识别的橡胶衬套耐久性仿真研究

Simulation Research on Durability of Rubber Bushing Based on Identification of Hyperelastic Constitutive Parameters

为解决道路试验中扭力梁衬套开裂的问题,基于虚拟试车场(VPG)仿真道路载荷谱,考虑三轴耦合编制了衬套三轴块谱作为疲劳仿真和台架试验的载荷输入,以某种橡胶材料超弹性初始本构参数为基础,分别按Mooney-Rivlin模型和Yeoh模型计算衬套3个方向的静刚度曲线,并与实际测试曲线比较定义优化目标,优化后的超弹性本构参数的刚度曲线与实测曲线吻合良好。利用裂纹扩展法预测橡胶衬套寿命,仿真结果与台架试验结果吻合良好,并以此为基础对衬套结构进行了优化,优化后衬套疲劳寿命明显提升。

To prevent torsion beam bushing from cracking during road test,the three-axis block spectrum of torsion beam bushing is defined as the load input of bushing fatigue simulation and rig test based on the Virtual Proving Ground(VPG)load spectrum,with consideration of 3 axis coupling.Taking initial hyper elastic constitutive parameters of a kind of rubber material as basis,the static stiffness curves along 3 directions are simulated respectively with Mooney-Rivlin model and Yeoh model that are compared with the actual test curve to define the optimization target.The stiffness curve of the optimized hyper elastic constitutive parameters agrees well with the measured curve.The rubber bushing fatigue life is simulated by crack propagation method,the results agree well with rig test results.Based on this simulation,the bushing structure is optimized,which shows obvious improvement of fatigue life.