Mechanics Property Analysis Of Spatial DK-Joints With Square And Circular Hollow Section

Among the directly welded CSHS(square and circular hollow section)joints,DK-type CSHS joints are popular structural types,which consist of twoK-type at an angle.Since DK-type CSHS joints’excellent integrative performancemakes they were widely used in engineering practice.But there are no relativespecifications in code for design of steel structures,that makes it difficult to designtubular DK-joints.This paper analyze nonlinearly the81DK-joints considering geometricnonlinearity and material nonlinearity by ANSYS finite element program.Theinfluence of joints geometrical parameters β、γ、τ、θ on failure mode and ultimatestrength of tubular DK-joints is studied.Analysis shows that DK-joints mainly havethree major failure mode:plastic failure of branch pipe、combined plastic failure ofthe combined branch pipe and plastic failure of main pipe.analysis also shows thatthe parameters β、γ、τ have a significant impact on the joints’bearing capacity,andthat the parameter θ has no significant impact on the joints’ bearing capacity.Finallyanalysis shows the joints’bearing capacity go down under the increasing constantly force ofthe main pipe.Some strengthening solutions are suggestted for the various modes of jointsfailure.