缠绕肋缠绕过程试验及力学行为分析

EXPERIMENTS AND MECHANICAL BEHAVIOR OF WRAPPING PROCESS OF LENTICULAR WRAPPED-RIB

首先通过单向拉伸试验测试和理论计算两种方法得到4层(45/45/45/45)铺设碳纤维复合材料的弹性模量,作为文中数值计算及弯矩分析的材料参数。通过4层(45/45/45/45)铺设碳纤维复合材料肋进行整体缠绕过程试验,得到肋整体缠绕过程肋表层应变和缠绕弯矩。利用ABAQUS分别建立了复合材料肋整体缠绕精细有限元模型,实现了缠绕一周过程强几何非线性数值模拟分析,得到各层应力、应变特征和缠绕弯矩,并与试验结果比较分析。进而给出缠绕弯矩解析表达式,并对材料铺设与厚度进行分析,得到缠绕过程最优材料铺设机理与最大厚度分析方法。该文对缠绕肋设计和深入研究具有重要参考价值。

Firstly, the elastic modulus of CFRP laminate which is four-ply （45°/-45°/45°/-45°） lay-up was obtained from the uniaxial tensile test of strip, which has little difference with that theoretically calculated based on composite material mechanics, so it can be used as material parameters in numerical simulation and wrapping moment analysis. The wrapping experiment of CFRP laminate Lenticular Wrapped-Rib （LWR） was performed, and the strain in the LWR surface and the wrapping moment were measured during the wrapping process. By using ABAQUS package, the three-dimensional finite element models （FEM） were built to simulate the wrapping process of the CFRP LWR. The wrapping process is highly nonlinear, including large deformation, small strain and complex contact problems. The structural behavior characteristic parameters during wrapping a circle were obtained analytically and compared with experimental results, including the stress, the strain and the wrapping moment. As a result, a formula for the wrapping moment was given. Moreover, the effects of material lay-out and thickness of the LWR were analyzed, and the optimum material lay-out and optimum thickness were obtained. The numerical procedure and experimental results presented in this paper are valuable to the optimum design of LWR.