摘要
将弹塑性材料模型与损伤演化模型耦合构建碰撞仿真的本构模型,在GISSMO损伤演化模型基础上引入应力状态对失效的影响。基于Al6061不同应力状态试件试验的仿真校验材料模型参数,实现高速列车侧墙结构碰撞过程的失效响应分析。研究结果表明:在Al6061试验中,相比于常数失效应变,损伤演化模型的仿真误差明显偏小;在碰撞中,失效单元内的应力三轴度随空间位置、碰撞历程在-0.67~0.67之间反复变化,随应力三轴度升高,失稳应变、损伤累积导致的实际失效应变逐步降低;同时,弹塑性模型与损伤演化模型揭示了高速列车侧墙结构碰撞过程的弯曲、褶皱变形与损伤积累,直至局部出现失效,避免了常数失效应变、不考虑失效条件下掩盖材料劣化过程而对结构承载的理想化预测。
The elastoplastic material model and the damage evolution model were coupled to construct a constitutive model for collision simulation,and the influence of stress state on failure was introduced on the basis of the GISSMO damage evolution model.Based on Al6061 tests in different stress states,the material model parameters were verified,and the failure response of the high-speed train sidewall was analyzed.The results show that the error of the damage evolution model is much smaller than the constant failure strain in the Al6061 tests.In the crash simulation,the stress triaxiality in the failure element varies between-0.67 and 0.67 with different spatial positions and collision time.As the stress triaxiality increases,the instability strain and the failure strain caused by damage accumulation decreases.In the impacting process of the high-speed train sidewall,the elastoplastic model and damage evolution model reveal bending,wrinkle deformation and the accumulation of damage until local failure occurs,which avoids the idealized prediction of structural carrying capacity without considering the deterioration process of materials when constant failure strain is used or failure condition is ignored.
作者
刘文
张乐乐
茹一帆
LIU Wen;ZHANG Lele;RU Yifan(School of Mechanical,Electronic and Control Engineering,Beijing Jiaotong University,Beijing 100044,China;National International Science and Technology Cooperation Base,Beijing Jiaotong University,Beijing 100044,China)
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2022年第5期1834-1842,共9页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(52172353)。
关键词
碰撞仿真
损伤演化模型
应力状态
失效分析
crash simulation
damage evolution model
stress state
failure analysis
