Behavior of Columns Constructed with Fibers and Self-Consolidating Concrete

Abstract

Steel fiber reinforced concrete was first developed in the 1960s, but the use of this material in load-carrying structural elements has not yet gained wide acceptance. This paper describes a series of 13 full-scale axial compression tests that was conducted on reinforced concrete (RC) and steel fiber-reinforced concrete (SFRC) columns. The objectives were to gain a better understanding of the performance enhancements that can be gained from the use of SFRC in columns and to examine if the provision of fibers would permit a reduction of confinement reinforcement. The specimens, which were detailed with varying amounts of transverse reinforcement, were cast using self-consolidating concrete (SCC) that contained various quantities of fibers. The results demonstrate that the addition of fibers leads to improved load-carrying capacity and post-peak response, and greatly delays cover spalling. The findings also show that the addition of steel fibers can partially substitute for the confinement reinforcement in columns, thereby improving constructability while achieving significant confinement. Although an addition of moderate amount of fibers to SCC can result in an adequately workable concrete mixture, there is a limiting fiber content above which the SCC mixture can lose much of its workability.