ABSTRACT ONLY:
A long, elegant lift bridge in Rouen, France, features two movable spans that can be raised to any height thanks to an ingenious butterfly-shaped pulley system that optimizes both the structural and mechanical designs.
BIOS:
By Michel Moussard. P.E., the director for civil engineering and bridges of Arcadis in France, and Michel Virlogeux, Ph.D., an independent bridge designer and consultant based in Bonnelles, France.