动荷载作用下含损伤复合材料层合板承载能力

研究了含分层损伤层合板的动力响应和承载能力。基于层合板的一阶剪切理论,采用分项等参插值方法推导了复合材料层合板刚度阵、质量阵列式,在瑞利阻尼的基础上构造了相应的阻尼阵列式;建立了用于含分层损伤复合材料层合板动力分析的分层模型和虚拟界面联接单元,以防止低阶模态中在分层处出现的上、下子板不合理的脱离和嵌入现象;同时又采用Tsai提出的0.44刚度退化准则和动力分析的Newmark法,对含分层损伤复合材料层合板结构进行了在动荷载作用下的破坏和承载能力分析;通过典型算例,分别讨论了外载频率,分层位置,以及刚度退化对含损伤复合材料动力响应特征和承载能力的影响。本文中提出的方法和得到的结论对复合材料工程设计具有参考价值。 

LOADED CAPABILITY OF DELAMINATED COMPOSITE PLATES UNDER DYNAMIC LOADING

The dynamic response behavior and loaded capability were investigated for the delaminated composite plates considering the failure process. A formula of element stiffness and mass matrices for the composite laminates was deduced by using the first-order shear deformation theory combined with the selecting numerical integration scheme. A damping model was constituted on the basis of Rayleigh damping model. A delaminated constrained model and a virtual interface element were also developed for avoiding the overlap and penetration phenomenon between the upper and lower sub-laminates at the delamination region. The failure analysis method for the delaminated plates under dynamic loading was established by Tsai's failure criterion and corresponding 0.44 reduced stiffness role, and the dynamic equation was solved by the Newmark direct integral method. By some numerical examples, the effects of the frequency of dynamic load, delamination location, and reduction of structure stiffness during the failure process upon the dynamic behavior and loaded capability of the delaminated composite laminates were discussed. The method and conclusions would be useful for composite structure designers.