Hána Tomáš, Janda Tomáš, Schmidt Jaroslav, Zemanová Alena, Šejnoha Michal, Eliášová Martina, Vokáč Miroslav
Klokner Institute, Research and Experimental Institute of Building Materials and Building Structures, Šolínova 7, 166 08 Prague 6, Czech Republic.
Department of Mechanics, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7, 166 29 Prague 6, Czech Republic.
Materials (Basel). 2019 Jul 11;12(14):2241. doi: 10.3390/ma12142241.
An accurate material representation of polymeric interlayers in laminated glass panes has proved fundamental for a reliable prediction of their response in both static and dynamic loading regimes. This issue is addressed in the present contribution by examining the time-temperature sensitivity of the shear stiffness of two widely used interlayers made of polyvinyl butyral (TROSIFOL BG R20) and ethylene-vinyl acetate (EVALAM 80-120). To that end, an experimental program has been executed to compare the applicability of two experimental techniques, (i) dynamic torsional tests and (ii) dynamic single-lap shear tests, in providing data needed in a subsequent calibration of a suitable material model. Herein, attention is limited to the identification of material parameters of the generalized Maxwell chain model through the combination of linear regression and the Nelder-Mead method. The choice of the viscoelastic material model has also been supported experimentally. The resulting model parameters confirmed a strong material variability of both interlayers with temperature and time. While higher initial shear stiffness was observed for the polyvinyl butyral interlayer in general, the ethylene-vinyl acetate interlayer exhibited a less pronounced decay of stiffness over time and a stiffer response in long-term loading.
事实证明，准确地对夹层玻璃板中的聚合物中间层进行材料表征，对于可靠预测其在静态和动态加载状态下的响应至关重要。在本论文中，通过研究两种广泛使用的中间层（由聚乙烯醇缩丁醛制成的TROSIFOL BG R20和乙烯-醋酸乙烯酯制成的EVALAM 80-120）的剪切刚度的时间-温度敏感性来解决这个问题。为此，已经执行了一个实验项目，以比较两种实验技术（i）动态扭转试验和（ii）动态单搭接剪切试验在为后续校准合适的材料模型提供所需数据方面的适用性。在此，注意力仅限于通过线性回归和Nelder-Mead方法的组合来识别广义麦克斯韦链模型的材料参数。粘弹性材料模型的选择也得到了实验支持。所得的模型参数证实了两种中间层的材料特性随温度和时间的变化很大。虽然一般来说聚乙烯醇缩丁醛中间层的初始剪切刚度较高，但乙烯-醋酸乙烯酯中间层的刚度随时间的衰减不太明显，并且在长期加载中响应更硬。
