In-plane bending hysteretic behavior of cruciform diaphragm welded joints with axial force

Cruciform diaphragm welded joints (CDWJ) has been adopted in large-span single-layer latticed shell as a new type of joint. The behavior of such kind of joint has not been well studied and understood. In this paper, the in-plane bending hysteretic behavior with axial force of CDWJ was investigated by performing both experimental tests in full scale prototypes and nonlinear numerical analyses. The results in terms of behavior, ultimate load and collapse mode were analyzed and compared. Experimental and numerical analysis results had good agreement for the CDWJ. Parametric analysis was performed on 14 CDWJ considering the influence of geometric size of components, angle between tubes and the axial compressive ratio. Moreover, Menegotto-Pinto mathematical model was established to describe the nonlinear rotation stiffness of CDWJ.