Abstract：Inclined loading conditions cannot be avoided in traffic accidents and strongly influence the mechanical response of cellular material.In present study, based on explicit dynamic finite element simulation by LS-DYNA, deformation modes as well as dynamic responses of a concave triangle with negative Poisson's ratio structure undergoing non-ideal oblique impact loadings have been investigated considering as significant parameters of the load angle (ranging from 0° to 10°) and the impact velocity (ranging from 20 m/s to 70 m/s), and corresponding mode classification map was constructed.Evident influence of asynchronous loading as well as impact speed on the deformation mode evolution has been determined.The concept of optimal bearing angle was introduced.When the load angle is β=4°, a stable and orderly deformation mode was induced.The form of resisting deformation is mainly based on the compression and bending of the structural cell wall, so that the platform stress value and energy absorption value have been made a great improvement.The anti-bearing capacity of the structure has been further exerted, even exceeding the ideal axial impact condition.The present study provides a significant advancement to the comprehensive understanding of the dynamic response of cellular material, which could be used to develop more valuable guidelines for design purposes in automotive energy absorbing devices.
马芳武，梁鸿宇，赵颖，陈实现，蒲永锋. 倾斜荷载下内凹三角形负泊松比材料的面内冲击动力学性能[J]. 振动与冲击, 2020, 39(4): 81-87.
MA Fangwu，LIANG Hongyu，ZHAO Ying，CHEN Shixian，PU Yongfeng. In-plane dynamic crushing of concave triangles materials with negative poisson’s ratio under inclined load. JOURNAL OF VIBRATION AND SHOCK, 2020, 39(4): 81-87.
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