双模量复合材料层合结构承载极限的预测

PREDICTION OF LOAD LIMIT OF BI-MODULUS COMPOSITES LAMINATED STRUCTURE

基于三维连续介质损伤力学模型,针对双模量纤维增强树脂基(BFRP)复合材料层合结构提出了一种改进的渐进损伤分析方法。首先,根据双模量材料的双线性模型以及正交各向异性材料本构理论,给出了BFRP单层板的应力-应变关系描述方法。其次,采用Dvorak就位强度模型计算了单层板的就位强度。并且,采用三维Hashin强度准则以及指数型材料损伤演化准则描述层合板的内部损伤起始与演化,使用内聚力单元描述层间的力学行为。进而,借助Abaqus材料子程序Umat编写了BFRP层合结构的渐进损伤分析程序。通过与文献试验结果的比较验证了新方法的正确性。最后利用该方法,对某空间站BFRP臂杆结构的承载极限进行了仿真分析,得到了相应的预测结果。

Based on three dimensional continuum damage mechanics,an improved progressive damage analysis method was proposed for bi-modulus fiber-reinforced polymer(BFRP)composites laminated structure.Firstly,according to the bi-linear model of bi-modulus materials and constitutive theory of orthotropic material,the stress-strain relation for BFRP composites lamina was described.Secondly,in-situ strength of lamina was calculated using Dvorak model.Plus,damage initiation and its evolution inside laminates were described by three-dimensional Hashin strength criterion and the exponential damage evolution criterion,and the cohesive element was used to describe the interlaminar mechanical behavior.Then,the progressive damage analysis code for BFRP composites laminated structure was realized through ABAQUS material subroutine UMAT.The new method was verified by comparing to the experimental results in literatures.Finally,this method is used to examine the load limit of a BFRP arm structure which is a part of space station and obtain the prediction results.