Performance of double-skin truss-reinforced composite wall under axial compression

In order to improve the buckling capacity of double steel concrete composite wall (DSCW), a new-type of double -skin truss-reinforced composite wall (DSTCW) with steel truss used as stiffeners was proposed. In total, 7 DSTCWs were loaded axially, and the variables included steel truss joint spacing and rebar diameter. The effects of those variations on the axial load-displacement curve, ultimate strength and failure mode were discussed. The results showed that the steel truss significantly improved the ability of steel plate to resist local buckling, and enhanced the composite action between steel plate and concrete. The larger steel truss joint spacing reduced the ultimate bearing capacity of the DSTCWs under axial compression, and the rebar could effectively resist the deformation of steel plates on both sides. Based on the test results, the finite element (FE) models were estab-lished and verified to discuss the working mechanism of DSTCWs, and an extensive parametric analysis was performed to find the key parameters on the mechanical behavior of DSTCWs. Formula for predicting the axial load capacity of DSTCWs was proposed.