黏弹性结构蠕变屈曲特性的分析  

CHARACTERISTICS OF CREEP BUCKLING FOR VISCOELASTIC LAMINATED PLATES

作　　者：彭凡[1] 傅衣铭[1] 

机构地区：[1]湖南大学工程力学系,长沙410082

出　　处：《力学学报》2003年第3期353-356,共4页Chinese Journal of Theoretical and Applied Mechanics

基　　金：教育部博士点专项科研基金资助项目(20020532018)

摘　　要：分析了线黏弹性正交铺设层合板的蠕变失稳问题,由相空间的特征方程解出临界载荷,经Laplace数值反演得到屈曲载荷与时间的关系;然后,通过建立扰动模型和分析变形的有界与无界增长,讨论了黏弹性结构延迟失稳的特性,解释了临界载荷与失稳时间的具体含义.In this paper, the time-dependent characteristics of buckling loads for simply supported viscoelas-tic cross-ply laminated plates under uniaxial compression in the x direction is investigated and it's meanings is explained. The Boltzman's hereditary constitutive relationship is used to model the mechanical behavior of composites. Based on the first order shear deformation theory, using Laplace transform of the governing equations and the numerical inverse method, the critic buckling loads and critic time are obtained. By constructing a transverse disturbed model and according to the bounded or unbounded growth of deflection, the time-dependent feature of bucking loads is illustrated. Based on the present analysis and numerical calculation some concluding remarks can be drawn. If the compression load is lower than the durable critic load, the deflection will vanish with the growing time although the transverse disturbed load is applied and kept for any time. If the compression load is higher than the durable critic load, and while the transverse disturbed load is applied, then unloaded after a given time and loaded again along the opposite direction promptly, the deflection will grow positively or negatively that depends on the applied compression load. This means there exist a critic value of compression load at which the deflection recovers to zero state and this critic value is defined as critic buckling load corresponding to the given time. Finally, a reasonable explanation of the delayed instability for the viscoelastic laminated plates is presented.

关 键 词：蠕变屈曲 黏弹性结构 层合板 临界失稳时问 扰动模型 材料力学 

分 类 号：TB301[一般工业技术—材料科学与工程]