夹层热钢化玻璃裂纹形态表征及开裂后力学行为

Fracture Morphology Characterization and Post-breakage Behavior of Laminated Thermally Tempered Glass

首先对随机分布的热钢化玻璃裂纹形态的表征方法进行研究,基于碎片面数、体积、球度参数的数据统计参数对裂纹形态分布特征进行控制,并采用Voronoi分布方法对裂纹形态进行表征。其次,引入组合有限离散元法来建立处于开裂后状态的夹层玻璃数值模型,并对开裂层碎片的Voronoi分布进行重构,结合试验结果研究热钢化玻璃碎片间嵌合作用及其关键参数对夹层玻璃后续力学行为的影响。结果表明:仅考虑碎片间的摩擦作用将显著低估夹层玻璃开裂后刚度,碎片间残余应变能和厚度方向上的不规则形态使碎片间相互作用仍然较强,宜用弱化的内聚模型来描述。通过内聚模型关键参数的迭代分析,建立了可较好预测夹层玻璃开裂后行为的组合有限离散元模型,并确定了关键参数对开裂后行为的作用规律。

A characterization approach for the random distributed fracture morphology of tempered glass was investigated. The global feature of fracture morphology was determined via statistical distribution parameters such as the face numbers, volume and sphericity of glass fragments. The Voronoi tessellation was introduced to characterize the fracture morphology. The numerical model of cracked laminated glass(LG) was proposed by a finite-discrete element method(FDEM). The fracture morphology using the Voronoi tessellation was reconstructed in such a model. The post-breakage behavior of LG due to the interaction behavior between fragments and corresponding key parameters was examined with the experimental data. The results show that the post-breakage stiffness of LG is underestimated by merely introducing friction between fragments. A degraded cohesive model can be used to describe the realistic interaction that is reinforced by the internal residual strain energy and irregular shapes in the thickness direction of glass fragments. Based on the iteration analysis of key cohesive parameters, the FDEM model for predicting the post-breakage behavior was established. The influence of key parameters on the post-breakage behavior was analyzed as well.