earticle

영어

In this study, we investigated experimentally the performance in accordance with the combination of the nylon fiber and steel fiber to improve the fire resistance of 100 MPa filling concrete to be applied to the CFT columns. To evaluate the performance of fiber combination, steel fiber contents and their lengths were varied. Test results showed that the fluidity was decreased with the increase of steel fiber due to enhanced viscosity and chargeability. For the compressive strength depending on steel fiber contents, the use of steel fiber and nylon fiber resulted in an increase of strength and reached design strength at 28 days. In addition, the use of blended hook type steel fiber with 40 kg/m3 had most favorable fire endurance performance withing this study. To maximize fire endurance performance due to fiber combination, steel fiber with 30mm as well as with 6 mm were combined. It was found that it the combination of long steel fiber and short one did not contribute to the improvement of the performances of fresh and strength properties of the concrete and fire endurance as well. Within this study, it is believed that the combination of Nylon fiber with 1.5 kg/m3 and long length steel fiber with 40 kg/m3 makes the concrete for CFT more fire endurable.