O Brien Caitlin, Zaghi Arash E
Civil and Environmental Engineering Department, University of Connecticut, 261 Glenbrook Road, Unit 3037, Storrs, CT 06269-3037, USA. caitlin.n.o'
Civil and Environmental Engineering Department, University of Connecticut, 261 Glenbrook Road, Unit 3037, Storrs, CT 06269-3037, USA.
Materials (Basel). 2018 Aug 4;11(8):1355. doi: 10.3390/ma11081355.
Lack of energy dissipation is one of the shortcomings of conventional glass fiber reinforced composites. The addition of steel fibers to the conventional FRP composite to create a hybrid composite has been recently investigated as an option to address this limitation. The current literature is limited to composites reinforced with metal and non-metal fibers of the same alignment. In this study, hybrid and nonhybrid FRP composites of different layups, fiber content, and weave type were manufactured and subjected to hysteretic tensile loads. Woven glass fabrics in ±45° orientation were hybridized with unidirectional stainless steel fabrics in 0° and 90° orientations. This put the glass and steel layers in in-plane shear and normal stresses, respectively. The nonlinear stress⁻strain relationship, residual plastic strains, energy dissipation capability, and failure mechanisms of hybrid and nonhybrid composite type were compared. The hybrid composites presented improved energy dissipation, tensile strength, and stiffness when compared to nonhybrid ones. The applicability of an existing constitutive model that was originally developed for in-plane shear of conventional composites was investigated and refinements were proposed to present the hysteretic stress⁻strain relationship after addition of steel fibers. The refined model captured the increased plastic strain values and energy dissipation because of stainless steel fibers in the hybrid composite samples. An Armstrong⁻Frederick plasticity model was implemented to model the stress⁻strain relationship of the stainless steel composite samples.
能量耗散不足是传统玻璃纤维增强复合材料的缺点之一。最近研究了在传统纤维增强复合材料中添加钢纤维以制备混杂复合材料，作为解决这一局限性的一种选择。目前的文献仅限于由相同排列的金属和非金属纤维增强的复合材料。在本研究中，制造了不同铺层、纤维含量和编织类型的混杂和非混杂纤维增强复合材料，并对其施加滞后拉伸载荷。将±45°取向的玻璃纤维织物与0°和90°取向的单向不锈钢织物进行混杂。这使得玻璃层和钢层分别承受面内剪应力和正应力。比较了混杂和非混杂复合材料类型的非线性应力-应变关系、残余塑性应变、能量耗散能力和破坏机制。与非混杂复合材料相比，混杂复合材料的能量耗散、拉伸强度和刚度有所提高。研究了最初为传统复合材料面内剪切开发的现有本构模型的适用性，并提出了改进方法，以呈现添加钢纤维后的滞后应力-应变关系。改进后的模型捕捉到了混杂复合材料样品中由于不锈钢纤维而增加的塑性应变值和能量耗散。采用阿姆斯特朗-弗雷德里克塑性模型对不锈钢复合材料样品的应力-应变关系进行建模。
