Abstract：Aiming at the colossal columns of Goldin Finance 117 tower in Tianjin, seven 1/20 scale polygonal multi-cell and self-compacting high-strength CFST columns were prepared. Based on axial compression tests, failure patterns of the specimens were investigated; the load-deformation curves and the load-strain curves were measured; the influences of factors such as concrete strength, thickness of steel tube and existence of steel reinforcement cage on the bearing capacity of column specimens were analyzed. The results indicate that there are four phases during the entire axial compression process of the column specimens; the shape of specimens remains almost unchanged until 90% of the ultimate bearing capacity is reached. Concrete strength contributes most to the enhancement of the bearing capacity of column specimens; while the steel reinforcement cage contributes little to the enhancement of the bearing capacity; increasing the thickness of steel tube can not only enhance the bearing capacity of specimens, but it may also improve the ductility of specimens. Based on the test results and referring to the domestic and overseas design codes, a practical calculation formula for the bearing capacity of short multi-cell and self-compacting high-strength CFST in axial compression was put forward, and it was recommended for practical engineering design.
