Prediction of the complete flexural load-deflection curve of self-compacting concrete reinforced with hook-end steel fiber

The flexural performance is vital for evaluating the characteristics of steel fiber reinforced self-compacting concrete (SFR-SCC). Although the tested load-deflection curve is commonly used to predict the flexural performance, little research has been done on the tested curve prediction. In this study, the complete flexural load-deflection curves of SFR-SCC beam specimens were obtained by a four-point bending test. The hook-end steel fiber with a length about 25 mm, 30 mm or 35 mm was respectively added for SFR-SCC at volume fraction of 0.4 %, 0.8 %, 1.2 % or 1.4 %. The characteristic points of tested curves are statistically analyzed to build the prediction formulas for the initial cracking strength, the flexural strength, and the first and second residual flexural strengths. The formulas for predicting the complete flexural load-deflection curve of SFR-SCC are proposed, and verified by comparing with the test curves. Meanwhile, the distribution of steel fiber in concrete matrix of beam specimen was measured to explain the mechanisms of flexural performance of SFR-SCC.