高速磁浮列车异物冲击三维有序负泊松比夹芯结构阻抗机理

The negative Poisson's ratio structure becomes a new international frontier hot topic due to its unique mechanical properties. A great deal of relevant frontier achievements has been frequently presented in sub-journals of Nature, Science in recent five years. For a high-speed maglev train subjected to high impact from outside unexpected object, four key challenges happen, including: local damage, high-speed impact, scale correlation, and random loading. Aiming at them, this investigation proposed a new original concept: “three-dimensional ordered Poisson's ratio” to provide sufficient protection, in which, resistant mechanism was determined by means of theoretical modeling, numerical simulation and experiments. The emphases are put on the dynamic impact response evolution of typical super-light three-dimensional ordered negative Poisson's ratio structures, rate-dependent effect, geometric correlation between structure and impactor, and the structural resistant mechanism under random multi-point impact as well as optimization design. Key scientific problems as the construction of correlation between cell and response，characterization of strain-rate dependent model, matching criterion in geometric configuration, random impact load expression will be resolved. Local effect, strain rate-dependent effect, scale effect, and random effect will be explored, and the accumulation behavior, shape change and pattern evolution of cell hole of the 3D ordered CFRP-NC sandwich structure during high speed impact of car bodies are about to determine. These can propose the resistance method of sandwich structure and provide theoretical guidelines for design of new generation of light-weight train manufactured with CFRP structure.

负泊松比结构因独特力学性能成为国际前沿新热点，近5年被Nature, Science子刊密集报导。本项目针对高速磁浮列车异物冲击所面临的局部破损、高速冲击、尺度关联、随机受载4大关键问题，提出“三维有序负泊松比”阻抗新思路，采用理论建模、仿真及实验相结合的方法，重点开展典型超轻三维有序负泊松比结构动态冲击响应模式演化、异物局部高速冲击率效应、结构与冲击体间几何关联性、随机多点载荷作用下结构阻抗机制以及优化研究，解决胞元与动态响应模式间关联模型构建、率相关动态理论吸能模型表征与辨识、冲击体与受击体多几何尺度下平衡性匹配准则建立、有限大平面内随机异物群冲击载荷时空表达与实现四大关键科学问题，探明局部效应、率增强效应、尺度效应、随机效应的作用机理，揭示三维有序CFRP-NC结构异物高速冲击胞孔集聚行为及模式演变规律，提出阻抗方法，为新一代轻质复合材料列车设计提供基础理论支撑。

为实现高速列车等运载工具复合材料车身结构高效抵抗局部冲击的目的，本项目开展了异物冲击三维有序负泊松比夹芯结构阻抗机理研究。受限于实验条件和高速磁浮车实际工程化设计，主要以二维内凹蜂窝负泊松比结构、三维顶点基负泊松比结构、典型CFRP面板、CFRP增强板为对象，采用理论推导、数值仿真和实物试验相结合的方法，开展了负泊松比结构的形性演变规律研究；确定了负泊松比结构承受异物高速冲击时的胞孔集聚行为、形性演变及模式演化规律；进行了碳纤维复合材料在局部冲击载荷作用下的损伤机制、预测模型和增强机理研究；以冰雹为载体，开展了随机冲击碳纤维复合材料板及其夹层结构的研究，分析了CFRP夹芯结构承受高速冲击时的阻抗机制；扩展性地开展了多孔结构的冲击增强机理和声力耦合相关研究。本项目累计已发表论文49篇（其中JCR Q1区SCI论文45篇），出版专著1部、译著1部、编著1部，授权国家发明专利6项，另申请公开国家发明专利8项，培养毕业博士研究生4人、硕士研究生6人，完成了预期成果要求。