格构增强型泡沫夹层结构腹板剪切屈曲分析

SHEAR BUCKLING ANALYSIS OF WEB OF LATTICE ENHANCED FOAM SANDWICH STRUCTURE

基于双参数地基模型,分析了格构式增强型泡沫夹层结构的腹板在纯剪作用下的弹性稳定问题,讨论了泡沫芯材的存在对夹层结构腹板剪切稳定的影响规律、该理论分析模型的适用条件,通过有限元方法验证了该模型分析结果的合理性。分析表明,泡沫芯材的存在可以有效提高腹板的剪切稳定性能。即使芯材弹性模量较低,其提供的剪切刚度对于腹板的稳定也有着重要意义。随着腹板高厚比和芯材弹性模量的增加,泡沫对腹板提供的法向刚度控制作用越明显。芯材厚度是该模型结果准确与否的重要前提。从工程实用的角度,腹板区格的长高比对腹板剪切稳定的影响可以忽略不计。

Based on model of Pasternak elastic foundation, shear buckling strength of web of lattice-enhanced foam-sandwich structure was analysed and probed under pure shear stress, due to the existence of foam core.The applicable condition of the analytic model was discussed, whose rationality was confirmed in comparison with the data of FEM model.The results show that the analytic model can match with the FEM model very well if the core thickness could be guaranteed to some degree.The existence of the core can enhance the web stability effectively.The shear stiffness provided by foam core to the web stability is still of great significance, even if the Young＇s modulus of the core material is low.But with the increase of ratio of height to thickness of web, and the augmentation of the young＇s modulus of the core material, the normal stiffness from the foam core play a more controlled role on the web shear stability.The ratio of length to height could be omitted for the perspective of engineering application.