某大悬挑钢结构设计与施工关键技术讨论

Discussion of key design and construction technologies of a large cantilevered steel structure

某综合性办公楼地下2层,地上塔楼20层,裙楼5层。裙楼4层局部悬挑达20~25m。结合建筑造型和功能,利用4层整层空间,设置4.5m高的钢桁架,作为主悬挑构件。在悬挑桁架根部采用了交叉腹杆桁架,提高了桁架刚度与承载力。针对大悬挑桁架制定了具体的施工方案,对桁架在各施工阶段的挠度进行了监测,并与有限元分析结果进行对比。结果显示,悬挑桁架挠度实测值与计算值整体上吻合较好。

A comprehensive office building has 2 floors underground,20 floors above ground and 5 floors of skirt building.The fourth floor of the skirt building is partially cantilevered up to 20~25m.Combined with the building shape and function,the steel truss with 4.5m height was set up as the main cantilevered component by using the whole floor space of the fourth floor.The cross web truss was used at the root of the cantilevered truss,which improves the stiffness and bearing capacity of the truss.Specific construction schemes were formulated for large cantilevered truss,and the deflection of the truss in various construction stages was monitored and compared with the results of finite element analysis.The results show that the measured and calculated deflections of the cantilevered truss are in good agreement.