Extradosed bridge:
An extradosed bridge employs a structure that combines the main elements of both a prestressed box girder bridge and a cable-stayed bridge.[1][2]: 85 [3] The name comes from the word extrados, the exterior or upper curve of an arch, and refers to how the “stay cables” on an extradosed bridge are not considered as such in the design, but are instead treated as external prestressing tendons deviating upward from the deck. In this concept, they remain part of (and define the upper limit of) the main bridge superstructure. [Wikipedia]
Total gibberish to me. From a friend’s LinkedIn post, so I’ll omit the link and just quote:
A precast extradosed bridge, St. Croix Crossing is a hybrid of a concrete box girder structure and a cable-stayed structure. The extradosed design minimized environmental impacts by allowing tower heights to be below bluffs, while reducing the number of piers in the river. Minimizing environmental impact is important on any construction project, but especially so in this beautiful corridor which is protected by the National Wild and Scenic Rivers Act.
