大型碳纤维桁架结构模态试验及特性

Modal tests and properties analysis on truss structure of large scale carbon fiber

基于随机子空间识别方法,采用自然脉动试验研究了大尺度、轻质高强承力型碳纤维复合材料桁架结构的模态特性.基于该桁架结构本身的特点,提出了3个基本假设,结合实际应用中桁架结构的约束条件,设计了大型碳纤维复合材料桁架的模态试验方案,并对试验结果进行了详细分析,总结了其频率特性、阻尼特性及振型特点.结合锤击法试验和有限元方法,对试验结果进行对比分析,结果表明3个基本假设合理,试验方案有效,试验分析结果可靠.研究结果可应用于浮空器结构设计和健康监测.

Based on stochastic subspace system identification method,the modal properties of the truss structure of large scale,light weight,high strength,and force bearing type carbon fiber composites were investigated by ambient excitation.On basis of the characteristics of the truss structure itself,three fundamental assumptions were forwarded.In conjunction with the constraint conditions of the truss structure in practical applications,a modal test scheme for the truss of large scale carbon fiber composites was designed.Through detailed analysis of the test results,the characteristics of frequency,damp,and vibration mode were summarized.By hammer impacts test and finite element method,the test results were comparatively analyzed.It is proved that the three fundamental assumptions are reasonable,the test scheme is effective,the analytical results of the test are reliable.The research results are of essential meaning to the design of aerostat structures and their health monitoring.