旋转圆弧曲面索穹顶的预应力态分析和力学性能

Prestress analysis and mechanical performance of rotating arc curved-surface cable dome

提出一种母线为任意圆弧线的大矢跨比旋转圆弧曲面索穹顶的新形式.首先基于节点平衡原理,推导了旋转圆弧曲面索穹顶结构的索杆内力计算公式.然后研究了不同矢跨比与圆弧线矢长比对旋转圆弧曲面索穹顶结构预应力分布的影响,以了解结构预应力的分布规律和特性.最后,通过结构重力态的预应力损失分析、荷载态的极限承载力分析、荷载工况组合分析、几何参数对比分析以及模态分析,研究了旋转圆弧曲面索穹顶结构的静力性能与基本动力特性.结果表明,结构的刚度对厚跨比较矢跨比更为敏感、对矢跨比较圆弧线矢长比更为敏感,且半跨荷载较全跨荷载对结构更为不利.本文研究为索穹顶的分析计算、设计和造型提供了新形式和新思路.

This paper proposes a new form of cable dome with a large rise-span ratio rotating arc curved surface with an arbitrary arc line.Firstly,based on the principle of nodal balance,the calculation formula for the internal force of the rotating arc curved-surface cable dome was derived.Then,the influence of different rise-span ratios and arc line-to-length ratios on the prestress distribution of the cable dome structure was studied to reveal the distribution law and characteristics of the structural prestress.Finally,the static performance and basic dynamic characteristics of the cable dome structure was studied by the prestress loss analysis of structure under gravity,the ultimate bearing capacity analysis under load,the analysis of load combinations,the comparative analysis of geometric parameters and the modal analysis.The results show that the stiffness of the structure is more sensitive to the thickness-span ratio than the rise-span ratio,and more sensitive to the rise-span ratio than the arc line-to-length ratio,while the halfspan load is more unfavorable to the structure than the full-span load.The research in the paper provides new forms and new ideas for the analysis,design and modeling of the cable dome.