Calladine C R
Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, UK
Philos Trans A Math Phys Eng Sci. 2015 Apr 13;373(2039). doi: 10.1098/rsta.2014.0346.
Davies Gilbert's work on the catenary is notable on two counts. First, it influenced Thomas Telford in formulating his final design for the Menai Strait suspension bridge (1826); and second, it established for the first time the form of the 'catenary of equal strength'. The classical catenary is a uniform flexible chain or cable hanging freely under gravity between supports. The 'catenary of equal strength' is the form of a cable whose cross-sectional area is made proportional to the tension at each point, so that the tensile stress is uniform throughout. In this paper I provide a sketch of the lives and achievements of Gilbert and Telford, and of their interaction over the Menai Bridge. There follows a commentary on Gilbert's 1826 paper, and on his two related publications; and a brief sketch of the earlier history of the catenary. I then describe the development of the suspension bridge up to the present time. Finally, I discuss relations between mathematical analysts and practical engineers. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society.
戴维斯·吉尔伯特关于悬链线的研究在两个方面值得关注。其一，它对托马斯·特尔福德设计梅奈海峡悬索桥（1826年）的最终方案产生了影响；其二，它首次确立了“等强度悬链线”的形式。经典悬链线是一条均匀的柔性链条或缆索，在重力作用下自由悬挂于两个支撑点之间。“等强度悬链线”是指这样一种缆索形式，其横截面积与各点处的拉力成正比，从而使整个缆索的拉应力保持均匀。在本文中，我简述了吉尔伯特和特尔福德的生平与成就，以及他们在梅奈桥项目上的互动。随后对吉尔伯特1826年的论文及其两篇相关出版物进行了评论，并简要回顾了悬链线的早期历史。接着我描述了悬索桥直至当今的发展历程。最后，我探讨了数学分析家与实际工程师之间的关系。这篇评论文章是为庆祝《皇家学会哲学学报》创刊350周年而撰写的。
