COMPOSITE ACTION OF FOAMED AND LIGHTWEIGHT AGGREGATE CONCRETE

An experimental study was conducted to investigate the composite action of foamed and lightweight aggregate concrete. Thirty-six push-out tests were performed on concrete-filled steel hollow sections of square and circular shapes. Bond strength between steel and concrete in composite sections depends on several factors. The shape of the cross section, the age, and the type of concrete were considered in this study. The test results reported show that lightweight aggregate concrete offered higher bond strength than normal concrete, and the strength of bond in foamed-concrete–filled specimens was about 40% of the strength in normal-concrete–filled specimens. The experimental results also show that the load-slip behavior of foamed and lightweight aggregate concrete–filled specimens is similar to that of normal-concrete–filled specimens.