研究双闭室复合材料薄壁梁的结构阻尼特性.基于单层混杂材料的细观力学阻尼计算方法和多胞模型,分别获得单层复合材料的等效阻尼特性和等效弹性特性；基于变分渐进法(VAM)和Hamilton原理,建立双闭室复合材料薄壁梁振动方程；采用Galerkin法对薄壁梁进行自由振动分析；在获得薄壁梁振动模态矢量的基础上,根据最大应变能理论,对薄壁梁的模态阻尼性能进行预测,并且将阻尼预测的结果与现有的有限元计算结果进行对比,验证了该阻尼分析模型的有效性.进一步针对四种种构型双闭室复合材料薄壁箱形梁,进行阻尼计算,揭示了纤维铺层角和纤维含量的影响.%Structural damping features of a the damping of thin-walled composite two-cell beam were presented. The micromechanic damping theory for fiber composite materials was employed to evaluate the damping capacity of the composite beam. The equations of motion of the beam were derived using Hamilton's principle combined with variational asymptotic approach(VAM). Galerkin's method was used in order to solve the coupled differential equations. Analytical formulas of the modal damping of the beam were derived according to the maximum strain energy theory. Comparison of the results from the theoretical solutions and those obtained from the finite element method was done. Numerical results were obtained for 4 layup cases of a two-cell composite box beam. The effects of fiber orientations and fibre volume fraction on modal damping were investigated.
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