The axial compression performance of stainless steel tube-confined concrete with a circular hollow section: Experimental results

The strength under axial compression of a design of stainless steel tube-confined concrete column (SSTCC) was tested in laboratory experiments, type of load-bearing column. In the proposed design the stainless steel tube merely restrains the concrete and does not directly bear the axial load. The test confirm the design's superior strength inaxial compression. On this basis, this paper proposes a new design of stainless steel tube-confined concrete with a circular hollow section (SSTCC-CHS), which combines the characteristics of SSTCC and CFDSST column. It has the superiority in high strength, light weight, high economy and easy installation. The influence of hollow ratios, the diameter-to-thickness ratios of the components and concrete's strength on the column's failure mechanism, ultimate compressive strength, stiffness, strain, restraint effect and ductility are documented through experiments. The ultimate strength is shown to be inversely proportional to the hollow ratios and the diameter-to-thickness ratios.It directly proportional to the concrete's strength. The design's mechanical properties is compared with that of SSTCC and CFDSST columns. In virtue of the superposition principle, a formula for predicting the bearing capacity of SSTCC-CHS columns in axial compression is proposed, and the formula is discussed according to different strength calculation models of confined concrete.