大跨度异形索网天幕变形分析及施工工艺研究

Study on Deformation Analysis and Construction Process of Large-span Shaped Cable Network Canopy

城市大型地下空间施工面积大、施工周期长,施工期间可能对城市面貌和环境造成负面影响。此外,由于地下空间表面形式的不规则,对搭设临时覆盖体系带来了挑战。为此,本文提出一种新型大跨度异形索网天幕施工技术。以广州塔南广场项目为例,通过数值模拟对不同天幕支撑方案进行了计算对比,并对新型施工技术的关键要点进行分析,得出了以下结论:采用本文提出的钢索网与钢桁架结合的方案与仅采用钢索网方案相比,天幕支撑结构竖向变形大幅降低了83.11%;与钢结构屋盖相比,在达到相同最大竖向位移时,采用钢索网加钢桁架的方案能够显著降低96%钢材用量;网格布作为天幕不仅具有防尘、耐高温、防雨水冲刷、环保等诸多优点,还能最大程度降低建筑施工对周边居民生活和环境的负面影响,在城市内大型地下空间施工项目中具有广泛的应用前景。

The construction of large urban underground spaces has a large area and a long construction period,which may have a negative impact on the urban landscape and the environment during construction.In addition,due to the irregularity of the surface form of the underground space,it brings challenges to erecting a temporary covering system.For this reason,this paper proposes a new type of large-span anisotropic cable network canopy construction technology,taking the Canton Tower South Square project as an example,calculating and comparing different canopy support schemes through numerical calculations,and analyzing the key points of the new construction technology,and the following conclusions can be drawn:the vertical deformation of the canopy support structure is substantially reduced by 83.11%using the combination of steel cables and steel trusses proposed in this paper compared with only the steel cable network scheme.Compared with the steel roof,the steel cable network with steel trusses can significantly reduce the steel consumption by 96%when the same maximum vertical displacement is achieved.Mesh cloth as a canopy not only has many advantages such as dustproof,high temperature resistance,rainwater washout,environmental protection,etc.,but also can minimize the negative impact of building construction on the life of the surrounding residents and the environment,and has a wide range of prospects for application in large-scale underground space construction projects within the city.