Fiber reinforced cementitious composites – architectural applications

Concrete serves the humanity as an important structural material. While concrete was always used only with steel reinforcement in the past, nowadays, several fiber types have been developed for different application areas. Thus, to reinforce concrete may not be limited only to rebar, fiber addition for enhanced ductility (e.g. link beams in coupled shear walls or bridge joints) or for moderate ductility (e.g. façade panels, aesthetic designs) has been introduced to application areas from laboratory conditions. In the scope of this Thesis, historical development of concrete technology is summarised. The types and characteristics of fibers and their utilization areas are adressed. Then, especially, the technology of engineered cementitious composites (ECC) has been focused; the types of fibers, mix design, workability, physicaland mechanical characteristics are explored in detail. An experimental research study on façade panels were conducted within a private sector firm with their material, production and laboratory support. The utility possibility of basalt fibers instead of glass fibers were experimentally studied on panels in view of the production technique (premix and spraying), fiber sizes, mix design, physical and mechanical characteristics. From the experimental studies on the panels, that only cement was used, basalt fibers are superior than glass fibers in view of ultimate bending strength and deformation in early curing period (up to 7 days). However, there is a need to enhance ultimate deformation in 28 days and especially the transition from ductile to brittle deformation characteristic in aging period. As a result, ıt may be concluded that the basalt fibers may be used as an alternative to glass fibers by enhancing final deformation characteristics. In the First Section of the study, the literature summary, purpose and methodology are given. The Second Section gives knowledge about the development of concrete technology, fiber reinforced concrete technologies and architectural applications. In the Third Section; glass fiber reinforced concrete (GFRC) and engineered cementitious concrete (ECC) are investigated in view of mix design, mechanical characteristics through the experimental data and actual architectural applications. In the Fourth Section; an experimental study was carried out on the utility possibility of basalt fibers instead of standard glass fibers for exterior façade elements. In the Fifth Section; the results and recommendations of this Thesis are presented.