气撑式张弦结构静力试验研究及有限元分析

基于气撑式张弦结构的受力特点，设计制作2.5 m跨度的纺锤形气撑式张弦结构模型，研究在跨中两点集中荷载作用下结构变形和内力分布规律，考察内气压对结构受力性能的影响。通过对结构极限状态的分析，研究结构的破坏形态及失效机理。利用ANSYS软件构建了纺锤形气撑式张弦结构精细化有限元模型，实现结构从放样态到充气态再到受荷态的全过程数值模拟，并与试验结果进行了对比分析。结果表明：有限元分析与试验结果吻合较好，两种方法获得的结构位移和内力值均比较接近；试验模型在集中荷载达到1.98 kN时达到极限状态，失效模式表现为上弦构件的局部屈曲破坏和气囊端部膜材出现褶皱。

Static experimental research and finite element analysis of Tensairity

Based on the mechanical behavior of the Tensairity,a spindle Tensairity structure model of 2.5m span was designed and manufactured.Under two concentrated forces loading on the mid-span of the model,the deflection and the laws of internal force distribution of the model were investigated,and the influence of the internal air pressure on the static performance of the structure was studied.Through the analysis of the limit states for the structure,the fracture morphology and the failure mechanism were studied.Second,the refined spindle Tensairity finite element model was established by ANSYS.From initial state to inflated state and loaded state of the structure,the whole course numerical simulation was carried out,and the responses of the structure were compared with the results of the experiment.The results show that the results from numerical simulation and the experiment agree well.The displacements and the internal forces obtained from the two methods coincide basically.The test model reaches the limit state at the time of the concentrated force is added to 1.98 kN,and the corresponding failure mode is the local buckling damage of the upper chord member and the folding of the membrane at the end of the airbag.