摘要
宝安体育场车辐式张拉屋盖结构呈椭圆形马鞍面,索力分布不均匀。为制定一种索力控制精度高、对张拉设备要求低的张拉施工方法,进行了宝安体育场屋盖结构模型整体张拉试验及模拟分析,验证了"定尺定长设计与张拉技术"能够准确获得设计初始态预应力。该方法对索材定长下料,在施工现场不调节索长,具有张拉过程简单,便于控制索力的优点。试验模拟了张拉径向索、顶升飞柱、张拉环索、隔榀张拉径向索4种张拉方案,结果表明:张拉过程中上径向索具有"张紧-松弛-张紧"的变化过程;上径向索松驰时,飞柱会出现倾斜的现象,倾斜角度可达0.1 rad;4种张拉方案的操作难易程度有明显差异:张拉径向索方案所需的张拉力大,但是操作过程简单;顶升飞柱和张拉环索方案所需张拉力小,但需对结构节点和张拉设备做特殊设计;隔榀张拉径向索方案的工期最长。通过对上述4种张拉方案以及由张拉径向索方案演化出的3种分批张拉径向索方案的数值模拟分析和对比,为宝安体育场屋盖结构实际施工制定了张拉径向索的方案。
Spoke structural roof of Bao＇an Stadium has ellipse and saddle shape,which causes a non-uniform distribution of prestressing in cables.In order to create a tensioning scheme with high precision in controlling cable force amplitude and low demand for tensioning equipment capacity,tensioning experiment and simulation analysis of Bao＇an Stadium were carried out.The study results proved that the ＇design and tensioning with fixed size and length＇ technique can help cables exactly gain the desired initial prestressing.In this technique,cables are produced in fixed length and their length will not be adjusted in constructional site,which makes the tensioning process simple and cable forces easy to control.Four tensioning schemes were performed in the experiment,which were radial cable tensioning scheme,flying column elevation scheme,inner ring tensioning scheme and interval radial cable tensioning scheme.It is validated that the upper radial cables experience ＇tension-slack-tension＇ process and the flying columns incline when upper radial cable slack and inclination will be 0.1rad.The 4 tensioning schemes are quite different in operation.The radial cable tensioning scheme need larger tension forces but is simple to operate.The flying columns elevation scheme and inner ring tensioning scheme need smaller tension forces but special design for structural joints and tensioning equipment.The internal radial tensioning scheme spend the longest time.Through comparing the above four tensioning schemes and another three schemes evolve from radial cable tensioning scheme by numerical analysis,radial cable tensioning scheme is chosen for spoke structural roof of Bao＇an Stadium.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2011年第3期1-10,共10页
Journal of Building Structures
关键词
车辐式结构
预应力
静力试验
张拉方案
spoke structure
prestressing
static test
tensioning scheme
