【作者】 周小军；

【导师】 黄立新；

【作者基本信息】 广西大学 ， 固体力学， 2008， 硕士

【摘要】 复合材料是当今社会各领域中被广泛使用的一种先进材料,准确地测定复合材料的材料参数是工程设计与评价的基础。目前国内外对正交各向异性复合材料的参数识别进行了大量的研究,针对目前测量方法存在的问题,本文提出了一种融合有限元法和最优化方法的正交各向异性复合材料结构的材料参数识别方法。该方法是以有限元计算为基础的正交各向异性复合材料的反分析方法。通过建立以测量位移与有限元计算的相应位移之差的平方和作为目标函数,把反分析问题转化为极小化目标函数的问题。采用Levenberg-Marquardt方法解极小化目标函数的问题,其中灵敏度的计算是基于离散的有限元代数矩阵方程对识别材料参数的求导。本论文提出的方法充分利用了有限元建模的通用性,为正交各向异性复合材料结构的材料参数识别开辟了一条新途径。数值算例表明本文提出的方法是行之有效的。更多还原

【Abstract】 The composite material is a kind of advanced material widely used in every field of the society nowadays. Therefore, calibrating the material parameter of composite materials accurately is the foundation of design and evaluation of engineering structure.Substantial research on parameter identification of composite materials is discerned both at home and abroad at present. Directed towards the existing problems of measuring method at present, this thesis has put forward a kind of material parameter identification method of orthotropic composite structure that integrates finite element methods and optimization techniques.Based on the finite element method, an inverse method is developed to identify the material parameters of orthotropic composite structure. The inverse problem is formulated as the problem of minimizing the objective function defined as a square sum of differences between the measured and calculated data on displacements. Levevberg-Marquardt method, in which sensitivity analysis is based on the differentiation of the discretized algebraic finite element matrix equations, is used to solve the minimization problem.The method that this thesis put forward has fully utilized modeling commonability of finite element method, opens up a new way for the material parameter identification of orthotropic composite structure. Numerical example shows that the proposed method for parameter identification is effective.更多还原