大跨度钢结构公共建筑屋面改造技术

Roof Reconstruction Technology of Large-span Steel Structure Public Building

既有大跨度钢结构建筑使用功能发生改变后,为了满足办公建筑对屋面防水、消防排烟、采光、隔热、舒适、节能、环保及美观方面的要求,需逐项改造并满足各种指标要求,改造方法施工工艺复杂,改造效果差,难以达到预期效果,还有可能带来其他新的问题。为了解决这一技术难题,本项技术采用组合设计方法:中间部位采用ETFE气枕式膜结构(部分设置成熔断膜,熔断膜数量和位置根据消防排烟要求进行设计),屋面边缘部位保留原有的铝单板屋面,ETFE气枕和铝单板之间的区域为新增设的铝镁锰金属屋面。本项技术与常规的改造方法相比,具有结构简单、施工简便、改造效果好等优点。

After the function of existing large-span steel structure buildings have changed,in order to meet the requirements of office buildings for roof waterproofing,fire and smoke exhaust,lighting,heat insulation,comfort,energy saving,environmental protection and aesthetics,their roof need to be reconstructed.Conventional reconstruction methods need to reconstruct item by item so as to meet various index requirements.It make the construction process of the reconstruction method very complicated,but the reconstruction effect is poor and often difficult to achieve the expected effect.Besides,it may also bring other new problems.In order to solve this technical problem,the paper proposed technology adopts a combined design method:the middle part adopts ETFE air pillow type membrane structure(part of it is set as fuse membrane,and the number and location of fuse membrane are designed according to the requirements of fire protection smoke),Tthe original aluminum veneer roof is retained at the edge of the roof,and the area between the ETFE air pillow and the aluminum veneer is the newly added aluminum-magnesium-manganese metal roof.After the reconstruction is completed,the existing large-span steel structure public buildings can meet the requirements of various indicators.At the same time,compared with conventional transformation methods,this technology has the advantages of simple structure,simple construction and good transformation effect.