Abstract

Although engineers can analyse demanding structures, basic understanding of the structural behaviour is not always clear to them. This is particularly true with cable-stayed bridges having asymmetric spans and inclined or even curved towers. To improve this situation, the present paper with a new simple design approach method is introduced. The method is useful at the conceptual design stage, when only the geometry of the bridge and the approximate weight of the main span is known or easily estimated. No deeper-going computer analysis is needed, but knowledge of basic graphic statics is required. In the paper, analytic formulae are derived for the cable quantity and balancing loads needed. Only harp-type cable-stayed bridges are discussed. The approach is based on the so-called force–length method and curtain cables. The formulae are useful when comparing alternative bridge solutions, or when determining the back-span cable forces and balancing weights needed, especially with curved towers.

摘要

尽管工程师可以分析要求苛刻的结构，但他们对结构行为的基本理解并不总是很清楚。对于具有不对称跨度和倾斜甚至弯曲塔的斜拉桥来说尤其如此。为了改善这种情况，本文介绍了一种新的简单设计方法。该方法在概念设计阶段很有用，此时只有桥梁的几何形状和主跨的近似重量是已知的或容易估计的。不需要更深入的计算机分析，但需要基本的图形静力学知识。文中推导出了所需电缆数量和平衡载荷的解析公式。只讨论了竖琴式斜拉桥。该方法基于所谓的力-长度法和窗帘拉索。