Abstract:As the main bearing structure of two-hinge arch bridge, the arch hinge support is the key part of connecting the arch foot and abutment, and is the key link of control design. Because the hinge structure cannot be replaceable and is exposed to the air, the hinge structure is bound to be corroded by water and air. At the same time, due to the large tonnage and large stress, there is bound to be stress corrosion. Taking the arch hinge of Tianbaowan Bridge as an example, the 5 500-ton high-strength brass arch hinge is used for the first time in China. The arch hinge should be smooth in the force transmission, the stress distribution is reasonable and there is no stress concentration. The local stress of arch hinge of Tianbaowan Bridge is analyzed and calculated to verify the rationality and feasibility of its design.