沉降影响下大型悬挑钢桁架结构的施工预调值计算

THE CALCULATION FOR THE CONSTRUCTION PRESET VALUE OF LARGE CANTILEVER STEEL TRUSS STRUCTURE UNDER SETTLEMENT

为保证南开大学新校区大学生活动中心大悬臂钢桁架结构的设计位形,安装时需要对结构的各节点施加施工预调值。应用有限元软件MIDAS/Gen对结构进行整体分析,确定结构在恒荷载作用下的施工预调值;综合分析工程的地基、基础形式和基础顶部的结构形式,做出结构基础为刚体的假设,按线性关系确定考虑地基沉降的施工预调值。选取沉降量小、恒荷载作用变形小的节点为基点,建立施工预调值计算式,将计算结果应用于施工控制,满足了结构的设计位形要求。

In order to satisfy the displacement and deformation requirements for the design of the large cantilever steel truss structure of the Students＇ Activity Center in Nankai University new campus,the structure installation needs to provide construction pre-set deformation value for each joint of the structure. To define the pre-set deformation value of the structure construction,both the effect of structure of constant load and the influence of foundation settlement should be considered.Through analyzing the whole structure in MIDAS / Gen,the pre-set deformation value was determined under dead load.Based on the foundation, foundation form and major structure,the rigid foundation could be assumed, the pre-set displacement and deformation value of large cantilever steel truss structure under the subsidence was defined by linear relation. Selecting the joints with small displacement and deformation to establish a calculation formula for the pre-set deformation value,as a result,the pre-set deformation value of the overall structure was defined,the calculation results have been used for the construction control of the structure so as to make the final installation deformation reached the requirements.