Compressive Behavior of Circular Tubed Steel-Reinforced High-Strength Concrete Short Columns

Abstract

In this paper, a total of 12 circular tubed steel-reinforced concrete (CTSRC) short columns with high-strength concrete are constructed and tested under axial compressive load. The main variables of the test include diameter-to-thickness ratio and yield strength of the steel tube, concrete strength, and the steel ratio of the profile steel. The failure modes, axial load-displacement curves, and ultimate axial load of the CTSRC columns are analyzed systematically. It can be determined from the test results that all specimens exhibited shear failure under concentric loading. However, the shear cracks around the concrete circumference were not connected throughout the entire section due to the presence of internal profile steel. Moreover, as a result of double confinement provided by the steel tube and profile steel, the ultimate concrete strength and ductility of the CTSRC columns were enhanced significantly, which led to a considerable improvement to the axial capacity. Finite-element (FE) analysis is conducted on the CTSRC columns using ABAQUS software, and the results show that good agreement and satisfactory accuracy between the test observations and FE methods can be achieved. Therefore, the numerical simulation used in this study is relatively reasonable and accurate. Based on the effective FE model mentioned previously, extensive parametric analysis is performed, and a more accurate axial strength model is proposed. It is evident that good agreement of theoretical predictions and the test data from this paper and other relevant literature can be achieved using the proposed model.