铝合金弦支穹顶结构稳定性研究

Study on stability behavior of aluminum alloy suspend-dome

铝合金材料具有轻质高强、耐腐蚀性好等优点,在大跨度空间结构中应用广泛,单层网壳为其主要应用形式.已有研究表明,单层网壳存在不可忽视的稳定性问题.为提高铝合金单层网壳结构的稳定性能,通过引入预应力索撑体系,提出了铝合金弦支穹顶结构的概念.经对结构的整体稳定性能进行对比及参数化研究,发现预应力索撑体系的引入可以有效地提高铝合金单层网壳的稳定性,结构矢跨比越小,效果越明显,最大提升幅度可达80.8%;预应力索撑体系对铝合金单层网壳稳定承载力的提高率是其对单层钢网壳承载力提高率的2.7倍;铝合金弦支穹顶的稳定承载力与初始几何缺陷负相关,与撑杆高度正相关.

Aluminum alloy has the advantages of light weight,high strength and good corrosion resistance.It is widely used in large-span space structures,and mainly takes the form of single-layer reticulated shell.Research has shown that the stability of single-layer reticulated shell is an issue of concern.To improve the stability performance of aluminum alloy single-layer reticulated shell structure,the concept of aluminum alloy suspend-dome is proposed by introducing prestressed cable brace system,and a large number of parametric studies are carried out on its overall stability performance.The results show that the introduction of prestressed cable brace system can effectively improve the stability of aluminum alloy single-layer lattice shells.The smaller the rise-span ratio,the more obvious the effect;and the maximum increase can reach 80.8%.The improvement rate of the prestressed cable brace system on the stability bearing capacity of aluminum alloy single-layer reticulated shell is 2.7 times that of the steel reticulated shell.The stability bearing capacity of the aluminum alloy suspend-dome is negatively correlated with the initial geometric imperfections and positively correlated with the height of the struts.