The relation between fiber orientation and tensile behavior in an Ultra High Performance Fiber Reinforced Cementitious Composites (UHPFRCC)

In this study, the effect of the fiber orientation distribution on the tensile behavior of Ultra High Performance Fiber Reinforced Cementitious Composites (UHPFRCC) was investigated. The tensile behavior was explored separately in two stages; pre-cracking and post-cracking tensile behaviors. Pre-cracking tensile behavior is expressed using the mechanism of elastic shear transfer between the matrix and the fiber in the composites. Post-cracking tensile behavior was expressed as the combined behavior of the resistance by the fibers and the matrix, considering a probability density distribution for the fiber orientation distribution across crack surface and a pullout model of steel fiber. The effect of the fiber orientation distribution was found to be very small on pre-cracking behavior, but to be significant on post-cracking behavior of UHPFRCC. The predicted results were compared with the experimental results, and the comparison presented satisfactory agreement.