Abstract A novel method for the design of variable depth single span bridges having maximum depth at the ends and minimum depth at midspan is presented. These bridges are intended to be used for long span river crossings or highway overpasses, where only a single span is required, and the vertical clearance below needs to be maximized, and/or an aesthetically pleasing graceful shape is desired. The design is made possible by “fixing” the ends to “lock-in” negative moments, so that the positive moments at midspan are greatly reduced, and a shallow section may to be used. The method is developed and presented in two parts. The first part discusses and unifies the behavior of three very famous bridges (the Luzancy Bridge in France designed by Eugène Freyssinet, the Gänstor Bridge in Germany designed by Ulrich Finsterwalder, and the Pinzano Bridge in Italy designed by Silvano Zorzi). The second part describes the method in detail by virtue of a complete design example. Application of the method to other bridges is included, and abutment treatments to enhance the visual qualities are presented. This innovative bridge type will be of interest to those looking for a practical and elegant new bridge solution for long span bridges.

中文翻译：

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拱形单跨桥的设计

摘要 提出了一种设计两端深度最大、跨中深度最小的变深单跨桥梁的新方法。这些桥梁旨在用于大跨度过河或高速公路立交桥，其中只需要一个跨度，并且需要最大化下方的垂直间隙，和/或需要美观的优美形状。该设计通过“固定”端部以“锁定”负弯矩来实现，从而大大减少跨中的正弯矩，并且可以使用浅截面。该方法的开发和介绍分为两部分。第一部分讨论并统一了三座非常著名的桥梁（由 Eugène Freyssinet 设计的法国 Luzancy Bridge，由 Ulrich Finsterwalder 设计的德国 Gänstor Bridge，以及由 Silvano Zorzi 设计的意大利 Pinzano 桥）。第二部分通过一个完整的设计实例详细描述了该方法。包括将该方法应用于其他桥梁，并介绍了增强视觉质量的基台处理。这种创新的桥梁类型将吸引那些为大跨度桥梁寻找实用且优雅的新型桥梁解决方案的人。