交叉张弦桁架预应力施工过程分析与索力实测  

Prestressed construction analysis and cable forces measurement of cross truss string structure

作　　者：汤磊[1] 罗斌[1] 丁明珉 

机构地区：[1]东南大学土木工程学院,南京210096

出　　处：《东南大学学报（自然科学版）》2013年第6期1293-1298,共6页Journal of Southeast University：Natural Science Edition

基　　金："十二五"国家科技支撑计划资助项目(2012BAJ03B06)

摘　　要：为精确控制交叉张弦桁架预应力施工过程中的拉索张拉,以鄱阳湖模型试验研究基地后续工程模型试验大厅钢屋盖为研究对象,对比分析了交叉张弦桁架的单榀或整体张拉方法以及平面外稳定性.分析结果表明,单榀交叉张弦桁架具有良好的平面外稳定性,单榀张拉不仅能在较小的预应力下脱离胎架,而且可避免各榀间先后张拉导致的索力相互影响.研究了平面外频率法用于交叉桁架索力测试的可行性,测试了施工中两阶段预应力拉索的索力,并与理论值进行了对比分析.结果表明,施工完成后的拉索索力满足设计初始态的要求,通过取前两阶自振频率计算拉索索力并利用压力传感器测试修正计算长度,可达到较好的测试精度.For precisely controlling cable tension in the process of the construction of a prestressed cross truss string,the steel halls roof of the subsequent engineering model test in the Poyang lake model test research base was taken as the research object,and the comparative analysis of the tension method of a single cross truss string or the overall structure and the out-of-plane stability were per-formed.The results show that the out-of-plane stability of single cross truss string is good.The sin-gle cross truss string can be separated from the support frame under small tensile force,and the mu-tual influence of the adjacent cross truss string can be avoided.Therefore,the single cross truss string tension method is reasonable.Simultaneously,the feasibility of the out-of-plane frequency test method for cable force was studied.The forces of the prestressed cables were tested during the two stages of construction.The test results were compared with the theoretical values.The results show that the cable force after the completion of tensioning construction meets the requirements of the de-signed initial states.Cable force can be calculated considering the first two natural frequencies,and the calculated length of the cable can be corrected by using the pressure sensor,obtaining good accu-racy using the out-of-plane frequency method.

关 键 词：交叉张弦桁架 预应力拉索 张拉分析 索力测试 频率法 压力传感器法 

分 类 号：TU758[建筑科学—建筑技术科学]