Behavior of Steel Slag Concrete Subjected to Elevated Temperature

Recycling of materials has become a major interest for engineers. At present, the amount of slag deposited in storage yard adds up to millions of tons/year leading to the occupation of farm land and serious pollution to the environment, as a result of the rapid growth in the steel industry. Steel slag is made at 1500- 1650°C having a honey comp shape with high porosity. Using steel slag as the natural aggregate with a lower waste material cost can be considered as a good alternative for sustainable constructions. The objective of this study is to evaluate the performance of residual mechanical properties of concrete with steel slag as coarse aggregate partial replacement after exposing to high temperatures .This study investigates the behavior of using granulated slag as partial or fully coarse aggregate replacement with different percentages of 0%, 15%, 30%, 50% and 100% in concrete when subjected to elevated temperatures. Six groups of concrete mixes were prepared using various replacement percentages of slag exposed to different temperatures of 400 °C, 600 °C and 800 °C for different durations of 1hr, 1.5hr and 2hr. Evaluation tests were compressive strength, tensile strength, and bond strength. The steel slag concrete mixes showed week workability lower than control mix. A systematic increasing of almost up to 21.7% in compressive strength, and 66.2% in tensile strength with increasing the percentage of steel slag replacement to 50%. And the results showed improvement on concrete residual mechanical properties after subjected to elevated temperatures with the increase of steel slag content. The findings of this study give an overview of the effect of steel slag coarse aggregate replacement on concrete after exposed to high temperatures.