Suspension bridge types are present in the majority of larger suspension bridges. Although the earlier types of suspension bridges are suitable only for relatively short spans, all of the 14 longest bridges in the world are suspension bridges (see List of longest suspension bridge spans). Ignoring the possibility of pre-Columbian trans-oceanic contact, there were two independent inventions of the suspension bridge, in Eurasia (probably in China) and in Central and South America. Types of suspension bridge include the following: A pure suspension bridge is one without additional stay cables and in which the main cables are anchored in the ground. This includes most
Pontoon effect Pontoon effect The pontoon effect refers to the tendency of a vessel whose flotation depends on lateral pontoons to capsize without warning when a lateral force is applied. The effect can be sudden and dramatic because pontoon boats usually cannot rely on the righting effect of a keel (which contains ballast). The vessel is stable and self-righting up to the point that the centre of gravity shifts past the centre of buoyancy of the ship and the vessel rapidly capsizes. The pontoon effect is theoretically possible whenever the vessel's entire weight exceeds the buoyancy of the pontoon(s) on either side.