将各项同性修正偶应力理论推广到各向异性, 基于新的修正偶应力理论建立细观层合Timoshenko梁的大变形模型。由虚功原理推导出正交对称铺设的细观层合Timoshenko梁的基本方程, 该模型只含有一个材料细观长度参数。对均布载荷作用的细观层合简支梁大变形建立一个三角级数展开的算法。计算结果表明本模型可以用于细观层合梁的大变形尺度效应分析。
In this paper, the isotropic modified couple stress theory is extended to the anisotropic.A micro-scale nonlinear analysis of large deformation composite laminated Timoshenko beam model is developed based on new modified couple stress theory.The symmetric cross-ply governing equations for composite laminated Timoshenko beam has been derived from the virtual principle.This new model contains only one material length scale parameter and can be directly reduced to composite laminated Bernoulli-Euler beam model of couple stress theory.In addition, the numerical results show that the present beam model can capture the scale effects of statics of large deformation in microstructure.
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