柔性巨型摩天轮结构的非线性分析

柔性巨型摩天轮结构体型庞大，结构形式特殊，刚性轮缘与柔性拉索相结合，边界条件复杂，存在着温度、缺陷和冗余度等敏感性因素影响。本文结合某摩天轮工程实例，分析柔性巨型摩天轮结构轮缘和拉索的受力性态，合理选择初始态预应力度，优化结构性能。考虑初始缺陷分别对轮盘以及摩天轮整体结构进行稳定分析，研究其非线性屈曲特征。同时考虑几何非线性和材料非线性进行弹塑性极限分析，全面揭示其结构特性。分析和研究结果表明：预应力拉索的引入使得柔性巨型摩天轮结构具有明显的非线性特征，初始态预应力决定了结构受力性态，由辐射状拉索和立体桁架组成的轮盘结构提供了强大的抗侧和抗扭刚度，柔性巨型摩天轮结构稳定性能良好，塑性发展机制理想，最终破坏表现为强度破坏，弹塑性极限承载能力比较大，能满足摩天轮正常运行和暴风状态的要求。

Nonlinear Analysis of Flexible Giant Ferris Wheel

Flexible giant Ferris wheel is huge in figure and special in structure form. It integrates rigid rim with flexible cable. The boundary conditions are very complex and it is much influenced by the sensitivity factors such as temperature, defect, and redundancy. Combined with a project example of flexible giant Ferris wheel, mechanical performance of rim and cable was analyzed. The rational initial prestressing force was chosen to optimize the structural behaviour. The initial imperfection was considered to perform the stability analysis of rim and overall structure. Nonlinear buckling characteristics was researched. Taking both the geometrical and material nonlinearity into account, the elasto-plastic limit bearing capacity analysis was carried out and its results comprehensively revealed the structural characteristics. The results of analytical study indicated that nonlinear characteristics of flexible giant Ferris wheel is obvious due to the introduction of prestressed cable. Mechanical performance of the structure depends on the initial prestressing force. The wheel consisting of radiate spoke cables and space truss provides strong lateral stiffness as well as torsional stiffness and the stability performance is favorable. The mechanism of plastic development is appropriate and its failure mode belongs to the strength failure. The elasto-plastic limit bearing capacity is so large that the wheel can satisfy the need both for operating condition and for storm condition.