粘接材料及结构在双轴受压和温度耦合作用下变形的尺度效应和非局部效应分析

Scale effect on buckling of bonding materials under biaxial compression with temperature changes

基于非局部理论,分析了双层完好粘接板在双轴受压和温度场耦合作用下屈曲的尺度效应和非局部效应.通过理论计算对经典弹性理论和非局部理论的计算结果进行了比较分析.结果表明:在非局部理论下,由于系统内部结构之间的相互作用,系统的屈曲临界力有所降低,并且当屈曲波数越大时,内部结构相互作用域进一步收缩,使得有效弯曲刚度减小,所以非局部参数对屈曲力的影响更为显著;在外载荷和温度耦合作用下,温度升高会导致屈曲临界力减小,温度降低会导致屈曲临界力增大.还对3种不同温度场进行了讨论,分析了在3种温度场下温度变化对外载荷的影响,以及与系统尺寸大小的关系.

The scale effect on buckling of bonding materials under biaxial compression coupled with temperature changes is studied. A developed nonlocal plate theory is applied to study the buckling behavior of the nonlocal multiple-plate model. The Navier＇s approach is used to obtain exact solutions for buckling loads under simply supported boundary conditions. The effects of the scale coefficient, wave number, thickness ratio, elastic modular ratio and temperature changes on the buckling loads are investigated. It is shown that the critical buckling force may be overestimated with the classical continuum theory. The nonlocal effect is proved to be more prominent for higher buckling modes. In addition, three kinds of temperature changes are taken into account. The influence of temperature changes on the buckling loads and the relationship with the system size are analyzed.