ABSTRACT
The limit analysis for axially loaded multiplanar CHS double X tubular joints by means of ring analogy model are formulated first at four load ratios. Thereafter, The equivalent width is regressed by the method of least square based on the computed ultimate strength of 14 multiplanar double X tubular joints at four load ratios by means of the finite element method The regression formulae for the static strength of multiplanar double X tubular joints at four load ratios are established. The limit load of other XX tubular joints under four load ratio and one test data are computed by present regression formulae. The present computed results are reasonably close to computed results by FEM and experimental data Finally the simple Monte-Carlo method is used to investigated the reliability of the static strength of the XX joints under different load ratios.
