45045 2018 eng Article 73, 1 13 3 51 article Springer Netherlands Dordrecht, Niederlande RILEM 1 -- -- -- Fiber-reinforced concretes (FRCs) offer significant improvements in tensile strength and durability compared to most other concrete mixes. However, for safe and efficient use of FRC in large structures, anisotropy of fiber orientation needs to be understood and properly controlled. In this project, both cored samples extracted from a FRC slab and FRC samples cast individually in molds were assessed using X-ray computed tomography (CT) and measurements of fiber orientation were extracted from the resulting CT images. These results showed that fibers within the slab were highly anisotropic in orientation while fibers in individually cast samples showed a much more heterogeneous distribution of orientations. This indicates that fiber orientation is highly dependent on the casting process and suggests that FRC can only be safely and efficiently utilized if anisotropic fiber orientation is properly accounted for during design and optimized casting methods are used during construction. Materials and Structures 10.1617/s11527-018-1198-8 https://rdcu.be/OR6k 1359-5997 1871-6873 xxx 07.06.2018 Tyler Oesch E. Landis D. Kuchma eng uncontrolled Anisotropic fiber orientation eng uncontrolled Computed tomography eng uncontrolled Fiber-reinforced concrete eng uncontrolled UHPC eng uncontrolled Hessian analysis eng uncontrolled Order parameter Ingenieurwissenschaften und zugeordnete Tätigkeiten Ingenieurbau Verlagsliteratur Datei im Netzwerk der BAM verfügbar ("Closed Access")