Cantilever spar cable-stayed bridge Cantilever spar cable-stayed bridge A cantilever spar cable-stayed bridge is a modern variation of the cable-stayed bridge. This design has been pioneered by the structural engineer Santiago Calatrava in 1992 with the Puente del Alamillo in Seville, Spain. In two of his designs the force distribution does not depend solely upon the cantilever action of the spar (pylon); the angle of the spar away from the bridge and the weight distribution in the spar serve to reduce the overturning forces applied to the footing of the spar. In contrast, in his swinging Puente de la Mujer design (2002), the spar
Pontoon bridge points. The "Palsey Pontoon" lasted until 1836 when it was replaced by the "Blanshard Pontoon" which comprised tin cylinders 3 feet wide and 22 feet long, placed 11 foot apart, making the pontoon very buoyant. The pontoon was tested with the Palsey Pontoon on the Medway. An alternative proposed by Charles Pasley comprised two copper canoes, each 2 foot 8 inches wide and 22 foot long and coming in two sections which were fastened side by side to make a double canoe raft. Copper was used in preference to fast-corroding tin. Lashed at 10 foot centres, these were good for