摘要
由于非凡的物理性能,石墨烯纳米片(GPL)被认为是最有吸引力的复合材料增强材料之一.GPL增强材料可以明显提高聚偏氟乙烯(PVDF)压电性能和力学性能.在力电载荷作用下,对含均匀石墨烯薄片增强(GSR)智能压电复合材料层合梁层间应力预测至关重要.若对受到力电耦合作用且层与层之间材料性能突变的压电层合梁层间剪切变形预测有误,则其层间应力过大可能导致层间失效.因此,论文提出一种适于分析此类问题且满足层与层之间相容性条件的有效力电耦合模型,用于含GSR致动器的复合材料层合梁层间应力分析.应用Reissner混合变分原理(RMVT),可以提高考虑力电耦合效应的横向剪应力预测精度.三维(3D)弹性理论和所选模型计算结果将用于评估所提梁模型性能.此外,还从力电载荷、压电层厚度、石墨烯体积分数和长厚比等方面对含GSR致动器复合材料层合梁力学响应特性进行了系统的研究.
Under the action of electromechanical loading,it is crucial to predict the interlaminar stress of laminated beams containing uniform graphene sheets-reinforced(GSR)smart piezoelectric composites.If the prediction of interlaminar shear deformation of piezoelectric laminated beams subjected to electromechanical coupling and the material properties vary widely from layer to layer,the interlaminar stress can be very large,which may lead to interlaminar failure.Therefore,an effective electromechanical coupling model is proposed for the interlaminar stress analysis of composite laminated beams with GSR actuators in this paper.First,the proposed model can satisfy the interlaminar continuity condition and only contains four independent unknown variables.By applying Reissner’s mixed variational theorem(RMVT),the improved transverse shear stress considering the electromechanical coupling effect is derived.The results obtained from three-dimensional(3D)elasticity theory and the selected model are then used to evaluate the performance of the proposed beam model.The responses of displacement and stress characteristics of composite laminated beams with GSR actuators are systematically studied from the aspects of electromechanical loading,thickness of piezoelectric layer,graphene volume fraction and aspect ratio.It is found that the results acquired from the present model agree well with the solutions of 3D elasticity theory.Moreover,a small volume fraction of graphene can significantly improve the stiffness of laminated beams containing GSR actuators,and further affect the displacement and stress of such structures.Therefore,adjusting the volume fraction of graphene helps to suppress the transverse deflection.Meanwhile,the electrical response of a thick laminated beam containing GSR actuator is more significant than that of a thin one.The thickness of piezoelectric layer has a significant effect on the electric performance of a laminated beam.In addition,the accurate prediction of interlaminar stress of beams can provide reference for the reliability and safety design of intelligent structures,which has great potential in engineering applications.
作者
马瑞
宋厚利
张超
Rui Ma;Houli Song;Chao Zhang(School of Aeronautics,Northwestern Polytechnical University,Xian,710072;Jilin Chongtong Chengfei New Material Company,Daan,131399;School of Civil Aviation,Northwestern Polytechnical University,Xian,710072)
出处
《固体力学学报》
CAS
CSCD
北大核心
2023年第1期34-46,共13页
Chinese Journal of Solid Mechanics
基金
国家自然科学基金项目(NSFC 11802007)资助
关键词
压电梁模型
锯齿理论
横向剪切应力
石墨烯增强
Reissner混合变分
electromechanical coupling beam model
zig-zag theory
transverse shear stresses
graphene-reinforced composite
Reissner’s mixed variational theorem
