Nonlinear Stress Analysis of Key Joints of Steel Truss Bridge

Steel truss bridges are widely used in bridge engineering for the advantages of good ability of spanning capacity, construction and light self-weight. Main trusses are the main stressed component of steel truss bridge. And the main truss are made of truss members connected by integral joints. So, the safety of integral joints are very important for normal operation of steel truss bridge. The superstructure of the continuous steel truss bridge with double decks was selected as the engineering example. The software, MIDAS/CIVIL is used to establish the full finite element model of the continuous steel truss bridge. Based on the results of the full bridge model, the 3D finite element model integral joint considering material nonlinearity was established by software Abaqus. The stress distribution of the integral joint under the unfavorable external force were analyzed and compared. The results showed that the most parts of the integral joint are in elastic stage, and the stress distribution is inhomogeneous. The stresses of integral joint are greater than that of truss members. Except for individual stress concentration areas, the stresses in the center area of the integral joint are greater than the stress at the edge. All in all, the safety of integral joints for the engineering example can be guaranteed.