研究损伤对开孔浅球壳非线性动力响应与动力屈曲的影响.基于Talreja张量内变量损伤模型,建立了纤维增强复合材料板壳弯曲问题的损伤本构关系,导出了考虑损伤效应的具轴对称变形正交各向异性开孔浅球壳的非线性运动控制方程.对未知函数在空间域采用正交点配置法离散,时间域采用Newmark-β方法离散.数值结果表明,由于损伤导致结构刚度不断削弱,结构振幅增大而频率减小,结构的动力临界屈曲载荷降低.
The influences of damage and damage evolution on the nonlinear dynamic response and dynamic buckling for thin shallow spherical shells with circular hole are investigated. Based on the Talreja's damage model with tensor valued internal state variables, the constitutive relations including damage of the bending problems for fiber-reinforced composite plates and shells are derived. Then the nonlinear governing equations of orthotropic shallow spherical shells with damage under axisymmetric deflection are obtained. For solving the equations, the unknown functions are separated by using the orthogonal point collocation method in the space domain and Nemmark- β schemein the time domain. Numerical results show that the vibrating amplitude of the structure will increase and the frequency will decrease by considering the damage effect. The results also indicate that the damage will reduce the dynamic buckling load of the structure.