Tensile behavior of fibrous concrete with conventional reinforcement - A theoretical study

The behavior of reinforced concrete (RC) with low amounts of conventional reinforcement may exhibit increased brittleness when fibers are added to the concrete mixture. The current paper presents a theoretical model to predict the cracking process of fibrous concrete bar with conventional reinforcement under increasing tensile load. This is a first stage of a study, which is intended to be a basis for a further development of a statistical model aimed at explaining the tensile (or flexural) behaviour described above. The model demonstrates the effect of residual tensile stresses at the cracked sections (σ_f), which are caused by the fibers, on the cracking process as compared to reinforced concrete without fibers. The model predicts the loads at which new cracks are formed, the crack locations and the distances between the cracks. These distances are not equal to each other as in plain RC. Initial results are compared with experimental data.