Reinforcement structure of truss bridge or arch bridge

Abstract

Through co-action between auxiliary triangular structural frames which are each constructed at opposite ends of a truss girder or arch girder and a cable stretched between the auxiliary triangular structural frames, an upward directing force is exerted to the truss girder or arch girder, thereby effectively inducing a load resisting force. A reinforcement structure of a truss bridge or arch bridge is comprised of a truss girder 2 or arch girder a first and a second end of which are each provided with a main triangular structural frame 6 which is further provided at an inner side thereof with an auxiliary triangular structural frame 9, the auxiliary triangular structural frame 9 being joined at vertexes thereof with frame structural elements at the respective sides of the main triangular structural frame 6, a cable 10 extending in a longitudinal direction of the truss bridge being stretched between a nearby part of the joined part at the vertex of the auxiliary triangular structural frame 9 on the side of the first end of the truss girder 2 or arch girder and a nearby part of the joined part at the corresponding vertex of the auxiliary triangular structural frame 9 on the side of the second end of the truss girder 2 or arch girder, deflecting means 11 adapted to exert a downward directing force to the cable 10 being inserted between the cable 10 and a lower chord 3 of the truss girder 2 or arch girder so as to tension the cable 10, an upward directing force being exerted to the lower chord 3 by a reacting force attributable to tension of the cable 10 through the deflecting means 11.

Dependencies are inferred from the claim text.