Static Strength of Circular Tubular T-joints with Inner Doubler PlateReinforcement Subjected to Axial Compression

For an inner doubler plate reinforced tubular joint, the doubler plate is welded onto the inner surface of the chord by using fillet weld, and the position of the doubler plate is placed under the brace/chord intersection. Through this reinforcement, the radial stiffness of the chord is improved, and hence the strength is increased. Finite element model is built by using software ABAQUS to analyze the ultimate load and failure mode of inner doubler plate reinforced tubular T-joints. Overall 432 models with different geometrical parameters and doubler plate sizes are analyzed. The effect of all the parameters on improving the static strength is discussed. Finally, a parametric equation for predicting the static strength of a tubular T-joint with inner doubler plate is presented through curve fitting technique, and its accuracy and reliability are also evaluated by error analysis.