Axial compression performance of planar DK-shaped diaphragm welded joints

Abstract

In order to study the axial compression bearing capacity of the planar DK-shaped diaphragm welded joints and the improvement of the bearing capacity caused by the internal stiffeners, axial compression tests were conducted on three joints with 1:4 scale-down model specimens, and the failure mode, deformation, bearing capacity and stress distribution of the test specimens were obtained. The test results show that the internal stiffeners can significantly improve the axial compression bearing capacity, initial axial stiffness and local buckling. The finite element model was established to study the effects of geometric parameters on the mechanical properties of the joints, such as the diameter of the chord, the ratio of the section radius to wall thickness of the chord, the ratio of the diaphragm thickness to the chord wall thickness, the ratio of the chord diameter to the stiffener width, the ratio of the stiffener thickness to the chord wall thickness. The mechanical model of planar DK-shaped diaphragm welded joint is established, and the calculation method of axial compression bearing capacity is given. The comparison between the experimental and numerical results shows that the established mechanical model meets the accuracy requirements.