以大型商用有限元软件ABAQUS为计算平台,提出了正交各向异性复合材料结构材料参数的识别方法。将材料参数识别的问题转化为极小化目标函数的问题,其中目标函数定义为测量位移与有限元计算的相应位移之差的平方和。采用Levenberg-Marquardt方法极小化目标函数,其中灵敏度的计算基于复合材料的有限元离散结构的求解方程对识别的材料参数求导。数值算例表明本文中提出的方法是有效的。在识别参数过程中,参数的初值以及搜索范围的确定对于识别结果有着重要影响。因此必须充分利用材料参数的先验信息。ABAQUS是高效可靠的商用有限元软件,提出的参数识别方法基于这类商用软件,因而该方法有很强的实用性。
Based on the computing platform of the finite element method commercial software ABAQUS, a parameter identification method was developed for orthotropic composite structures. The material parameter identification problem was formulated as the problem of minimizing the objective function defined as a square sum of differences between the measured and calculated data on displacements. Levenberg-Marquardt method, in which the sensitivity analysis was based on the differentiation of the discretized algebraic finite element matrix equations with respect to material parameter, was used to solve the minimization problem. Numerical example shows that the proposed method for parameter identification is feasible and effective. The initial values and upper and lower bounds of parameters identified play an important role in the parameter identification process. Therefore, a priori information of parameters should be used as much as possible. ABAQUS is effective and reliable commercial software for the finite element method, and hence the proposed method based on such a kind of software has strong practicability.