蜂窝纸板本构模型及其缓冲系统动力学行为分析

Honeycomb paperboard becomes a hot topic and commonly used in cushioning packaging domain because of its lightweight, degradable properties and good cushioning features. Nonetheless, it remains a significant challenge for honeycomb paperboard which exhibits exceptionally nonlinear behaviors and also depends on many factors, such as cell length, cell thickness, and compressive strain rates and so on. The objective of this project is to develop a comprehensive constitutive relationship of honeycomb paperboard on the basis of experimental stress-strain curves and predict impact responses of so-called critical components under the action of honeycomb paperboard to evaluate the failure law for packaged products. The main content includes: First, the tests will be performed to evaluate the influence of cell length, cell thickness, and pre-compression strain on the cushioning characteristics of honeycomb paperboard subjected to quasi-static and dynamic compressive loadings; Then, staring from the experimental results, constitutive law will be formulated for honeycomb paperboard;Finally, the impact responses of critical components with lumbered mass or simply supported beam type will be explored in detail . The research results will lay a foundation for evaluating failure behaviors of critical component during transportation.

蜂窝纸板具有轻质、可降解性和良好的吸收能量的能力，已成为缓冲包装动力学的研究热点之一。由于蜂窝纸板缓冲性能受胞元边长、胞元壁厚、预压缩应变和压缩应变率等因素的影响，且呈现强非线性，因此蜂窝纸板的宏观本构关系是工程技术界的难点问题。本项目通过试验研究胞元边长、胞元壁厚、叠置层数和预压缩应变在准静态和动态冲击下的应力-应变曲线，探明这些参数对应力-应变曲线的影响规律；进而建立蜂窝纸板强非线性本构方程；将具有简支梁式关键部件的包装物品简化为集中质量与简支梁，研究简支梁关键部件在蜂窝纸板缓冲系统作用的动力学响应规律。研究成果为揭示易损件在缓冲作用的失效行为提供理论依据，为解决产品运输包装具有重要工程价值。

鉴于蜂窝纸板在缓冲设计中有广泛的应用，本项目对蜂窝纸板一维本构模型、多层蜂窝结构的力学响应、易损件的冲击失效行为进行了实验分析、理论研究与数值模拟，在相关领域取得了一些成果。项目基于最低压缩应变率试验，提出了用于精确拟合蜂窝纸板应力-应变曲线所表现的线弹性、应力软化、屈服平台和压实等四个典型特征的形状函数，进而考虑胞元大小、基材料的力学性能、应变率因素等因素对蜂窝纸板应力-应变行为的影响规律，建立了蜂窝纸板较为全面的一维宏观本构模型；然后利用虚拟质量方法与有限元数值模拟对多层蜂窝结构逐层屈曲的变形模式与力学行为进行了较为准确的预测；项目最后利用解析方法与有限元数值方法研究易损件在蜂窝结构缓冲作用下的冲击响应与失效行为，并用最大响应应力作为评判物品损坏与否的标准。项目的研究能揭示蜂窝纸板在缓冲应用中的防护机理，为纸蜂窝材料在包装上的科学设计提供了理论依据，具有广阔的应用前景。