体内布索立体桁架挠度简化计算及性能分析  

Simplified calculation and performance analysis for deflection of 3D truss with internal cables

作　　者：史刘可 贺拥军[1] SHI Liuke;HE Yongjun(School of Civil Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]湖南大学土木工程学院,长沙410082

出　　处：《中国科技论文》2023年第4期378-385,共8页China Sciencepaper

基　　金：国家自然科学基金资助项目(51878261,51890902)。

摘　　要：为了研究体内布索方案在巨型网格结构中的作用效果,首先推导了体内布索立体桁架段在竖向荷载作用下的挠度计算公式,并利用ANSYS软件进行对比验证;在此基础上,分析了拉索在立体桁架中的作用效果,求解了结构参数一定情况下预应力的合理取值范围。然后选取单榀立体桁架拱与纵向立体桁架,对比分析了不同布索方案下结构的静力性能。结果表明:所推导的立体桁架段挠度公式计算精度较高,最大误差在5%以内,可作为整体结构关键节点挠度求解的理论依据;预应力拉索的引入改善了结构杆件的内力分布和结构变形,拱向立体桁架中仅布索段杆件内力发生改变;在各布索方案中,立体桁架拱跨中布索能最有效地减小结构最大竖向位移;纵向立体桁架各跨拉索预应力值根据弯矩极值成比例设置能最有效地改善结构静力性能,为最优方案。In order to study the effect of internal cable arranged in the reticulated mega-structure,the calculation formula for the deflection of the three-dimension(3D) truss with internal cables under vertical load was deduced,and the structure was solved by ANSYS software for comparison and verification.On the base of the above,the effect of cable in the 3D truss was analyzed,and reasonable range of prestressed value under the condition of certain structural parameters was determined.For the 3D-trussed arch and the longitudinal 3D truss,the static performance of structure with different arrangement types of cables was conducted.The results indicate that the calculational accuracy of the deduced deflection formula of the 3D truss is high,and the maximum calculational error is less than 5%,which can be used as the theoretical basis for solving the deflection of the key nodes of the overall structure.The adoption of the prestressing system can significantly improve the structural deformation and the internal force of member.In the 3D-trussed arch,the internal force of the structure which arranges internal cable is changed.The maximum vertical displacement of structure can be reduced most effectively when the cables are arranged at the middle span of 3D-trussed arch.The static performance of the longitudinal 3D truss can be improved most effectively when the pretension of cables is proportional arranged according to extreme bending moment,which is hereby the optimal arrangement scheme.

关 键 词：立体桁架 体内布索 挠度计算公式 布索方案 静力性能 

分 类 号：TU393.3[建筑科学—结构工程]