带裂纹层合板能量释放率分析

Analysis of Energy Release Rate for Cracked Laminates

为了进一步了解裂纹尖端应力场的特性，本文对复合材料层合板的界面裂纹作了分析。文中强调了能量释放率分量存在的条件，并给出能量释放率分量和应力强度因子间的关系式。结合经典板理论的分析结果，根据外荷作用及某些几何参数和材料多数，导出了一般复合材料层合板的应力强度因子的封闭形式解。为了得到在一般荷载条件下能量释放率的分量，必须分别确定模型混合参数Ω，文中讨论了确定参数Ω的方法，最后，应用本文方法于几种不同种类的复合材料层合板，证明其结果可应用于工程实践。

An interface crack analysis is presented for further under-standing the char- acteristics of the crack-tip field.The conditions under which the energy release rate components would exist are emphasized,and the relations between energy re- lease rate components and the stress intensity factors are given. Combining with the results of classical plate theory analysis,a closed-form solution for stress intensity factors in terms of external loading as well as some geometric and material parameters for fairly general composite laminates is derived.Then,an analytical solution for energy release rate components is deduced.In order to get energy release rate components under general loading condition,a mode mix parameter,Ω,must be determined separately. A methedology for dctermining Ω is discussed.Finally,several different kinds of laminates are examined ,and the results obtained could be used in engincering applications.