ABSTRACT
The Tiete-Parana is a navigation system mainly composed of affluents of rivers Parana, Tiete, Piracicaba, Grande and Paranaiba, comprising 2400 km of navigable routes, with 1642 km of main routes and 758 km of secondary routes.
Currently, the waterway transports approximately 5.7 million tons of cargo such as bran, soy, general grain, fertilizers, agricultural lime, wood, fuel and construction materials (iron, cement, ceramics, etc.). With the maturation of the MERCOSUL and the river participation in the system, it is expected to see an increase of transported cargo up to 20 million tons.
The waterway admits simple convoys of 2,200 tons or double convoys with 4,400 tons capacity, operating at speeds between 6 and 8 knots or 10 to 14 km/h, powered by tugs on its back or stern region, a factor that makes it difficult to pass under the many existing bridges along the waterway, due mainly to small clearance between piers as well as the occurrence of winds and waves when sailing in reservoir waters. Therefore, it has been recorded in recent years, several cases of collisions of vessels with bridge supports, even causing the ruin of them in certain situations.
It is noteworthy that many studies have been developed to mitigate this problem, regarding the expansion of horizontal clearance under the bridges, with the demolition of piers, duplicating spans, and the improvement and standardization of switchgear of vessels. The first project deals with the destruction of a pier and therefore two decks of Sao Jose dos Dourados Bridge, and the second project cover the expansion of Barrageiros Bridge’s horizontal clearance, both located on such Waterway in Northwest of Sao Paulo State.
