弦支穹顶局部环索断索动力冲击效应试验  

Dynamic Impact Effect Experiment on a Suspendome Subjected to Local Hoop Cable Rupture

作　　者：王霄翔[1,2] 陈志华[1,2] 刘红波[1,2] 金海 宋卫乾 

机构地区：[1]天津大学水利工程仿真与安全国家重点实验室,天津300350 [2]天津大学建筑工程学院,天津300350 [3]天津市建设工程技术研究所,天津300204

出　　处：《天津大学学报（自然科学与工程技术版）》2017年第11期1210-1220,共11页Journal of Tianjin University：Science and Technology

基　　金：国家自然科学基金资助项目(51478310);天津市建委科技项目(2014-1)~~

摘　　要：针对弦支穹顶结构在使用过程中可能遇到的环索断索问题,对弦支穹顶模型开展了局部环索断索动力冲击效应试验.通过对比环索不同初始预应力和不同索撑节点约束条件下的断索动力冲击效应,得到了局部环索断索对结构杆件内力和位移的影响及其规律.试验结果表明:断索点附近的杆件受到断索的影响会发生一定的运动和震荡,其内力也会发生波动,且索力越大、节点约束越弱,波动幅度越大;当索撑节点处无约束时,局部断索会引起结构整体的剧烈震动,且拉索在索撑节点处会发生较大的滑移,造成整圈环索内力大幅降低,严重影响结构安全;对于弦支穹顶结构,杆件内力的动力放大系数与结构杆件类型、位置、环索初始预应力水平、节点约束等均有关,需通过试验研究或动力分析等方法来准确获得.Dynamic impact effect experiment on a suspendome subjected to local hoop cable rupture was conducted considering that hoop cable rupture might happen during the service life.The dynamic impact effects caused by cable rupture under different cable forces and different constraint conditions of cable-strut joints were compared,and thus the influence and rules of the change of member internal force and displacement caused by cable rupture were obtained.Results showed that due to cable rupture,the members located near the rupture spot suffered a certain movement and vibration and the internal force of those members fluctuated after the rupture.The bigger the cable force was,and the weaker the constraint conditions of cable-strut joints were,the more dramatically the internal force fluctuated.With no constraint in cable-strut joints,local rupture would cause intense vibration of the whole structure,and significant cable sliding would occur in cable-strut joints,which would lead to a great decrease of cable force in the whole hoop cable,thus threatening the safety of the structure.For suspendome structures,the dynamic amplification factor of member internal force is related to the type of member,location,initial cable force of hoop cable,constraint condition of cable-strut joints and so on,which needs to be determined by experimental studies or dynamic analyses.

关 键 词：弦支穹顶 拉索 局部断索 滑移 动力冲击 动力放大系数 

分 类 号：TU394[建筑科学—结构工程]