论文部分内容阅读
目前大多采用Kantorovich逼近算法研究棱柱形平板和加劲薄壳结构的屈曲应力,该方法参考了Von Karman和Koiter-Sanders理论,当预测的屈曲模态涉及平面内和平面外位移的比较时,后者引入了Green-Lagrange应变张量的概念。此外,为了突出Koiter-Sanders模型的非线性特性,进一步考虑了两个中间模型,根据不同的理论方法选择了改进的Von Karman模型和伪似然模型,以简化数值计算。结果表明,至少从实用的角度看来,在所选择的3个模型的计算结果基本相同的条件下,在不能忽视平面内位移的屈曲问题中,Von Karman模型过高地估计了临界荷载。
At present, Krestorovich approximation algorithm is mostly used to study the buckling stress of prismatic plates and stiffened shell structures. The method is based on Von Karman and Koiter-Sanders theory. When the predicted buckling modes involve in-plane and out-of-plane displacement comparison, The concept of Green-Lagrange strain tensor is introduced. In addition, in order to highlight the nonlinearity of the Koiter-Sanders model, two intermediate models are further considered. According to different theoretical methods, the improved Von Karman model and the pseudo-likelihood model are selected to simplify the numerical calculation. The results show that, at least from a practical point of view, the Von Karman model overestimates the critical load in buckling problems that can not ignore in-plane displacements under the condition that the calculated results of the three models are basically the same.