Tam Meifung, Yang Zhicheng, Zhao Shaoyu, Yang Jie
School of Engineering, RMIT University, PO Box 71, Bundoora, VIC 3083, Australia.
Guangzhou University-Tamkang University Joint Research Centre for Engineering Structure Disaster Prevention and Control, Guangzhou University, Guangzhou 510006, China.
Materials (Basel). 2019 Apr 30;12(9):1412. doi: 10.3390/ma12091412.
This paper investigates the free vibration and compressive buckling characteristics of functionally graded graphene nanoplatelets reinforced composite (FG-GPLRC) beams containing open edge cracks by using the finite element method. The beam is a multilayer structure where the weight fraction of graphene nanoplatelets (GPLs) remains constant in each layer but varies along the thickness direction. The effective Young's modulus of each GPLRC layer is determined by the modified Halpin-Tsai micromechanics model while its Poisson's ratio and mass density are predicted according to the rule of mixture. The effects of GPLs distribution pattern, weight fraction, geometry, crack depth ratio (CDR), slenderness ratio as well as boundary conditions on the fundamental frequency and critical buckling load of the FG-GPLRC beam are studied in detail. It was found that distributing more GPLs on the top and bottom surfaces of the cracked FG-GPLRC beam provides the best reinforcing effect for improved vibrational and buckling performance. The fundamental frequency and critical buckling load are also considerably affected by the geometry and dimension of GPL nanofillers.
本文采用有限元方法研究了含开口边缘裂纹的功能梯度石墨烯纳米片增强复合材料（FG-GPLRC）梁的自由振动和压缩屈曲特性。该梁为多层结构，其中石墨烯纳米片（GPLs）的重量分数在每层中保持恒定，但沿厚度方向变化。每个GPLRC层的有效杨氏模量由修正的Halpin-Tsai微观力学模型确定，而其泊松比和质量密度则根据混合法则预测。详细研究了GPLs分布模式、重量分数、几何形状、裂纹深度比（CDR）、长细比以及边界条件对FG-GPLRC梁基频和临界屈曲载荷的影响。结果发现，在开裂的FG-GPLRC梁的顶面和底面分布更多的GPLs对改善振动和屈曲性能具有最佳的增强效果。基频和临界屈曲载荷也受到GPL纳米填料的几何形状和尺寸的显著影响。
