Experimental, numerical and analytical investigation of axial compression performance of angle steel lattice concrete composite column used in the prefabricated structures

The angle steel lattice concrete (ASLC) composite column is composed of angle steel lattice skeleton and concrete. It has a wide range of development potential in prefabricated buildings because of its ease of assembly similar to steel structures, structural performance and durability similar to concrete structures. Experimental, numerical and analytical studies are carried out in this paper to investigate the axial compression performance of ASLC composite column. Four fullscale specimens with various angle steel ratios and batten plate spacings were tested in order to investigate failure mode, axial deformation, and steel strain development law of the ASLC composite column. The experimental results also provide validation for the finite element modeling, and a parametric analysis of 20 model columns using Abaqus was carried out to reveal the impact of the angle steel ratio and batten plate volumetric ratio on the ultimate axial compression bearing capacity of the ASLC composite column. Results show that as the angle steel ratio increases, the ASLC composite column's axial compressive bearing capacity and peak deformation increase, while the batten plate volumetric ratio's effect on the axial compression performance is primarily seen in ductility. Based on theoretical analysis, experiments, and finite element studies, and considering that the core area concrete is confined by the steel skeleton, a calculation method for the axial compression bearing capacity of the ASLC column is proposed, which has good applicability. Furthermore, several design recommendations are made in this paper.