预应力空间网格结构的预应力施工控制理论研究  

Tensioning process control theory for prestressed reticulated structures

作　　者：周臻[1] 孟少平[1] 吴京[1] 

机构地区：[1]东南大学,江苏南京210096

出　　处：《土木工程学报》2007年第12期46-51,共6页China Civil Engineering Journal

基　　金：建设部软件科学研究资助项目(06K307)

摘　　要：针对预应力空间网格结构在在预应力施工过程中的实际状态与理论分析模型存在差异的情况,提出"预应力空间网格结构的预应力施工控制"问题。并从系统分析的观点出发,建立索力递推系统对该问题进行详细讨论,从理论上证明只有在索力间相互影响满足一定要求的情况下,恒以目标索力为索张拉力进行循环补拉才能使实际索力不断逼近目标索力,但逼近的速度受3个因素的影响:索力间相互影响、索数目、循环补拉开始前实际索力与目标索力的差值。索力间相互影响越大,索的数目越多,张拉开始前实际索力与目标索力相差越大,则实际索力逼近目标索力的速度越慢,为达到目标索力要求需要进行的循环次数也会增加。为此,提出"基于索力观测值的预应力施工方案决策"的概念,讨论两种基于索力观测值的预应力施工方案决策方法:数学方程法和迭代求解法。最后通过工程算例验证所提出的预应力施工控制理论的正确性。The actual state of prestressed reticulated structures in tensioning process differs much from that in theoretical model. From the viewpoint of system analysis, the deductive system of the cable forces is established. It is proved theoretically that if the interactive influences of cable forces meet certain requirements, the actual cable forces can approach the targeted cable forces when the tensioning cable forces are consistently taken as the target cable forces, and the convergence rate is affected by three factors. When the interactive influence of cables, the number of cables, and the difference between the actual cable forces and the target cable forces are larger, the convergence rate is slower and the required cyclic tensioning time increases. It is proposed that the stretching scheme should be based on observed values of cable forces, and two decision-making methods are discussed. Finally, an example is provided to demonstrate the effectiveness of the proposed tensioning process control theory.

关 键 词：预应力空间网格结构 预应力施工控制 预应力分析 索力递推系统 预应力施工方案决策 

分 类 号：TU394[建筑科学—结构工程]