Effect of Recycled Aggregate Replacement on High Temperature Performance of Steel and Polypropylene Fiber Concrete

Abstract

Concrete is used as one of the basic building materials of the construction industry, while sustainability goals, such as reducing environmental impacts and using natural resources more effectively, are driving the industry to new pursuits. In this context, understanding the effects of recycled aggregate substitution of %1 steel and %0.1 polypropylene fiber reinforced concrete on high temperature exposure in concrete is important from both environmental and structural perspectives. In this study, the high temperature performance of fiber reinforced recycled aggregate substituted concrete was investigated. Polypropylene fiber at 0.1% of the concrete volume and steel fiber at 1% were added and substituted into each of the 0-2 mm, 4-8 mm and 8-16 mm aggregates at a ratio of 10-20-30-40%. The specimens were cured for 90 days followed by compressive and flexural tests. The cube specimens were then exposed to elevated temperatures (300°C, 500°C and 700°C) to investigate the changes in compressive strength and loss weight. The results showed that the recycled aggregate substitution did not significantly change the compressive and flexural strength of the concrete except for 40%.