预应力施工随机误差对弦支穹顶结构静力性能的影响分析

Analysis of static performances of suspen-dome structures considering the random errors influence of prestressing construction

以山东茌平体育馆弦支穹顶结构工程为背景,基于概率统计原理,研究弦支穹顶结构的各项力学性能对预应力施工过程中随机误差的敏感性.分析结果表明:弦支穹顶的变形对最外圈环索内力的误差最为敏感,跨中挠度有可能最大增大33.3%,且超过设计值5%的概率达到32.28%;在受力方面,各圈环索内力的变异将对其所在区域的网壳杆件和索撑体系的内力产生较大影响,但影响程度小于其对结构变形的影响.考虑到弦支穹顶结构最外圈环索在结构中的重要作用以及对结构的影响程度,建议预应力施工过程中严格控制最外圈环索内力的施工精度,同时施工过程中应注意结构的变形.

Taking the suspen-dome of Chiping Stadium as an example,the sensitivity of structural prerformance to errors during the process of prestressed construction was studied based on statistics and probability theory.The result indcates tha the deformation of suspen-dome is most sensitive to internal force errors of outermost ring cable .The deflection at the middle span can increase by 33.3%,and the probability of surpassing5%OF THE DESIGN CAN REACH362.28%.In terms of internal forces,the variation of internal force of each ring cable demonstrates a large influence on bars of latticed shell and cable-strut system,though slighter than that on structural deformation.Considering the importance of outermost ring cable in suspendome,it is recommended the construction precision of outermost ring cable and the structural deformation should be strictly controlled.