Experimental and Theoretical Comparative Study of Circular Steel Tubular Columns Filled with Self-Compacting Concrete under Axial Concentric Loading

Abstract

This study presents an experimental and theoretical study on the behavior of circular, concrete-filled, steel tube (CFT) columns filled with self-compacting concrete (SCC) concentrically loaded in compression to failure. Specimens were tested to investigate the ultimate capacity and the load–deformation behavior of the columns. The behavior of these columns in confinement was discussed. The test results for acceptance characteristics of self-compacting concrete (SCC) such as slump flow; V-funnel and L-Box are presented. The experimental study was used to compare with theoretical results based on three different building codes. The codes used were the Eurocode 4 - EN 1994-1-1:2004 (EC4), ANSI/AISC 360:2010 and AIJ. The test specimens were of a length-to-diameter ratio (L / D) of 2.5, 6.25 and 9.375 respectively. The internal core is self-compacting concrete had nominal unconfined cylinder strength of 30 MPa. In general, the code provisions were of different accuracy in the prediction of column capacity. The AISC (1999) was the most conservative, while Eurocode 4 presented the values closest to the experimental results. The slenderness ratio was critical in determining the formation of a local buckle, and those slenderest columns only attained 85.7% of their section capacities.