STRUCTURAL SYSTEM FOR ARCH BRIDGES, WITH MOBILIZATION OF EXTERNAL REACTIONS THROUGH DEFINITIVE TIES

摘要

The application concerns the controlled addition of stiffness to arch bridge structures, through definitive ties systems (3), connected to external anchorages (8), prestressed to mobilize reactions, increasing the compression forces in the arch (1), in order to reduce the structure weight. The mobilization of the prestressed ties stiffness in tension or relative compression results in forces that directly balance external loads, transferring them to the foundations. The system of ties associated with the slender arch and the thin deck enables equilibrium of loads for which the arch does not have anti - funicular shape, such as variable live loads. The external anchored definitive ties system is responsible for the equilibrium of variable loads, so that the bending stiffness and strength of arch and deck can, therefore, be reduced.