超高层结构竖向变形与伸臂桁架安装控制方法研究

Research on vertical deformation and installation control method of outrigger truss for super high-rise structures

为在施工过程中采取有效的施工措施,控制完工后结构实际标高与设计标高的差异值以及伸臂桁架的附加应力,以西安金融中心为分析模型,综合混凝土收缩徐变理论、时变结构力学及有限元法等对不同伸臂桁架安装方案下的结构进行施工全过程仿真模拟,得到了施工过程中结构各层竖向变形变化规律以及不同安装方案下伸臂桁架附加应力。分析结果表明,混凝土收缩徐变在整个施工过程中所占竖向变形比例为47%-59%,伸臂桁架安装越早,结构封顶时产生的附加应力越大。结合控制论思想提出控制目标,通过实例给出超高层结构竖向变形与伸臂桁架安装控制方法,并验证方法的有效性。研究结果对超高层结构竖向变形变化规律的掌握具有参考价值,所研究的竖向变形和附加应力的控制方法对后续巨柱核心筒结构超高层施工具有指导意义。

In the construction process,effective construction measures are taken to control the difference between the actual elevation and the design elevation of the completed structure and the additional stress of the outrigger truss.The Xi'an Financial Center was used as an analytical model.The whole process simulation of the structure of different outrigger truss installation schemes was carried out by the concrete shrinkage and creep method,time-varying structural mechanics and finite element method.The variation law of vertical deformation of each layer of the structure during construction and the additional stress of the outrigger truss under different installation schemes were obtained.The analysis results show that the proportion of vertical deformation of concrete shrinkage and creep during the whole construction process is 47%-59%. The earlier the arm truss is installed,the more additional stress is generated when the structure is capped.Combined with the control theory,the control target w proposed.The vertical displacement of the super high-rise structure and the installation control method of the outrigger truss are given by examples,and the effectiveness of the method is verified.The research results has reference value for mastering the variation law of vertical deformantion of super high-rise structures,the vertical deformation and additional stress control methods have guiding significance for the subsequent super high-rise construction of the giant column core structure.