Compressive bearing capacity of CFRP-aluminum alloy hybrid tubes

Combining Al (namely, aluminum alloy) and CFRP (carbon-fiber-reinforced polymer) jackets to form structural members can yield many advantages and a bilinear behavior, which can enhance their advantages and mitigate any disadvantages. CFRP-Al hybrid tubes, which are used as axial load members in spatial structures, are investigated in this study by using compression experiments and a theoretical analysis. Formulas that describe the compressive bearing capacity with and without local buckling before yielding are proposed for stub hybrid tubes. In addition, their compressive behaviors are simulated by using the finite element method (FEM). A good agreement in the test results is achieved. The effect of the number of pairs of CFRP layers, the diameter-thickness ratio (DT ratio) and width-thickness ratio (WT ratio), and the fiber direction are described based on finite element analysis (FEA). Finally, a design approach for compressive CFRP-Al hybrid stub tubes is proposed.