索承网壳结构施工张拉索力的确定

基于有限位移理论,采用广义的杆系结构几何非线性有限元法,联系实际的施工方法和施工过程,提出了索承网壳结构施工计算的循环前进分析方法。该方法以实际施工顺序进行前进分析,以初应变增量索力调整方法进行循环迭代,能够精确计及结构的几何非线性、后批预应力筋张拉对前批预应力筋张力的损失以及其它因素的影响。用该方法获得的施工初始索力进行施工,设计索力及位形易于保证,是一种实用的、高效率的分析方法。编制的施工状态计算机仿真分析程序,可实现施工状态的实时跟踪分析与控制。

Determination of cable forces during construction for cable supported lattice shells

Based on the theory of finite displacement, the analysis method of cycle forward was presented firstly for the construction calculation of cable supported lattice shells, which adopted the finite element method of generalized geom etric non linearity and was combined with real construction method and procedure. By means of the forward analysis according to real construction sequence and cycle iteration according to adjustment of cable forces based on the increment of initial stress, the method could take into account the geometric non linearity of the structure, calculating loss of prestress due to prestressing of tendons in turn and so on. If the initial cable forces derived from the method were used for construction, expected cable forces and shape could be assured easily. So the method is quite practical and effective. The program for computer simulation analysis of construction state can realize track analysis and control at real time.