全复合材料桁架扭转刚度分析
Analysis of torsional stiffness of all-composite truss

为了解决全复合材料桁架扭转刚度缺少实验外有效表征手段的问题, 首先, 基于均匀化思想, 依据单胞剪切刚度相等原则, 将全复合材料桁架等效为闭口薄壁梁, 推导其等效扭转刚度;然后提出位移转换法并测量桁架转角, 对全复合材料桁架扭转刚度进行了实验研究;最后, 在梁单元桁架模型中嵌入精细化接头模型, 对全复合材料桁架扭转刚度进行了仿真分析。结果表明: 等效及仿真结果与实验值基本吻合, 等效分析方法能够有效预测全复合材料桁架的扭转刚度, 桁架仿真模型具有一定的工程实用性;实验方案可靠, 所提出的位移转换法能够解决小转角测量相对误差较大的问题。 To solve the problem of the lack of effective all-composite truss torsional stiffness characterization method except for experiment, based on the homogenization concept and according to the principle of equal single cell shear stiffness, the all-composite truss was equivalent to closed thin-walled beam to deduce their equivalent torsional stiffness firstly. Then the displacement conversion method was proposed and the torsional angles of truss were measured, and an experimental investigation on all-composite truss torsional stiffness was conducted. The fine joint models were embedded into truss model of beam elements to simulate and analyze the all-composite truss torsional stiffness finally. The results show that equivalent and simulative results agree with experimental values basically, which indicates that the equivalent analysis method can predict all-composite truss torsional stiffness effectively, and the truss simulation model has certain engineering practicability. Moreover, the experimental scheme is reliable, and the proposed displacement conversion method can solve the problem of larger relative errors of small angle measurement. 教育部新世纪优秀人才支持计划(NCET-08-0150)