This paper analyses Maillart’s Vessy Bridge from a design point of view using thrust lines. As it has previously been shown that Robert Maillart used graphic statics to design the line and the structural features of his bridges, it proves appropriate to reconstruct the working drawings of one of his most complete works. Thrust lines, forces trajectories and funicular polygons within the scope of graphic statics refer to reference loading cases and their choices. Furthermore, it questions the manipulation of forces, with mechanisms such as prestressing and interpreting thrust in geometrical terms.