非线性弹性大变形材料梁的抗爆特性

Blast-resistant properties of beams consisting of nonlinear elastic large deformation materials

从理论上探讨了非线性弹性大变形材料应用于抗爆结构的可行性,为此,基于等效结构体系的分析原理,将两端固定铰支梁的横向和纵向位移表示为三角级数形式,应用第二类Lagrange方程建立了非线性大变形材料梁的非线性分析方法,并且用ABAQUS有限元软件中的超弹性材料模型验证了所提出的方法的有效性。对典型的爆炸荷载作用下非线性弹性大变形材料梁的抗爆特性进行了分析,讨论了动力放大系数和材料性质及动荷载之间的关系。结果表明:与线弹性小变形材料相比,非线性弹性大变形材料具有优良的抗爆特性,结构的抗爆能力随结构变形的增大而显著提高。

Materials such as steel and reinforced concrete are frequently used in blast-resistant structures. However, analytical procedures for those structures are limited to elastic or elastic-plastic small deformations. This paper aims to discuss the feasibility of the application of nonlinear elastic large deformation materials to blast-resistant structures theoretically. Based on the principle of the equivalent structural system and the representation of the transverse and longitudinal displacements of the beam supported with immovable pinned ends by triangular series, a simplified nonlinear analytical method is derived for the beam consisting of nonlinear elastic large deformation materials by Lagrange＇s equations of the second kind. The effectiveness of the proposed analytical method is verified by ABAQUS finite element code, in which the nonlinear elastic large deformation materials are simulated by the hyperelastic model. The blast-resistant properties of the beams consisting of the nonlinear elastic material subjected to the typical blast loads are analyzed, and the discussions about the relationships among the dynamic magnification factor, material property, and the blast load are given. The analytical results show that the blast resistance of the beam consisting of nonlinear elastic large deformation materials is much better than that of the beam consisting of linear elastic small deformation materials, and the structural blast-resistance increases greatly with the increasing of the structural deformation.