Abstract:The Qingshuitang Bridge is a three-span continuous double-deck steel truss arch bridge with a main span of 408 m. Its side span is an open truss structure without transverse connection systems or planar connection systems. The upper chord node at the top of the pier is not only the layout point of the first transverse and planar connections of the entire bridge, but also the anchoring structure for construction clamping pylon, which is a key node for the force control of the entire bridge. The internal structure of this node is complex. The overall finite element model of the entire bridge is difficult to accurately reflect its detailed force state. Accordingly, the local refined solid modeling should be carried out based on the overall computing results. The research is conducted on the refined analysis technology of key nodes, and the construction of local models and the verification of their validity are completed. The static and stability calculations are carried out for two types of control conditions such as constant load and constant live load combination to clarify the force characteristics and stress distribution laws of this key node, which can provide a theoretical basis for the optimal design of node structures and the improvement of engineering construction.
