Edge Effects and Interior Solutions for Anisotropic and Composite Materials

许多有用的薄壁结构，如飞机和自动部件、火箭外壳、直升机叶片和各种安全壳，都是由各向异性、纤维或纤维增强材料层构成的。虽然这些结构中的许多都受到严重的机械、惯性或热载荷的影响，但它们的设计通常必须保持弹性。这意味着能够准确地计算全局特性，如屈曲载荷和固有频率，以及局部信息，如孔或边缘附近的应力，这一点尤为重要。建议研究这种构造的两个重要的互补区域，即没有陡峭应力梯度的内部区域和应力梯度高的边缘带(S)。对于这两个区域，将开发简化的、成本效益高的渐近方法。调查的范围将包括线性和非线性问题。众所周知，复合材料中非线性效应的考虑往往与线性化理论的预测有很大的不同。鉴于先进复合材料在当前技术中的快速应用，此类材料的大变形研究有望对知识和技术基础产生广泛影响。

Many useful thin-walled structures such as aircraft and automatic parts, rocket casings, helicopter blades, and a variety of containment vessels, are constructed of layers of anisotropic, filament or fiber-reinforced materials. While many of these structures are subject to severe mechanical, inertial, or thermal loads, they must often be designed to remain elastic. This means that it is particularly important to be able to compute accurately global characteristics, such as buckling loads and natural frequencies, as well as local information such as stresses near holes or edges. It is proposed to study two important, complementary regions of such structures, namely, the interior where there are no steep stress gradients, and the edge zone(s) where stress gradients are high. For both regions, simplified, cost-effective asymptotic methods will be developed. The scope of the investigation will include both linear and nonlinear problems. It is known that considerations of nonlinear effects in composites often lead to striking differences from predictions of linearized theories. In view of the rapid utilization of advanced composite materials in current technology, studies on large deformations of such materials promise to have widespread impact on the knowledge and technology base.