Experimental investigation of some properties of square concrete-filled steel tubular columns containing iron filings as replacement of sand

Abstract

This paper presents an experimental investigation of axial load projected onto concrete filled steel tube (CFST) columns and study the effect of using iron filings in the filled concrete mixture to improve the ultimate compressive strength, ductility index and energy absorption. Twelve column specimens was used in this study, three as reference and nine iron filings (CFST) column specimens as a partial replacement of sand by 2.5%, 5%, and 10% with 6 cubics,9 cylinder and 3 prisms samples of concrete of each column specimens. Three types of stub, short and long column. These tests include performing slump, compressive strength, tensile strength and flexural strength. The results show that the concrete with iron filings have the highest compressive strength at the age of 28 days’ageof 49.53Mpa,52,3Mpa and 55.63 Mpa, namely more than control mix by 11%,17% and 25%. However, ductility index and energy absorption of column specimens with iron filings become the highest at the age of 28 days.