Structural Behaviour of UHPC with Micro-Reinforcement

With intent to provide a ductile failure and to use Ultra High Performance Concrete (UHPC) to full capacity usually steel fibres are added during the mixing process. The impaired workability as well as random orientation and spreading of the fibres, the increased environmental pollution and the cost factor are beside the spots of corrosion resulting from near-surface fibres the main disadvantages in the use of micro steel fibres. Earlier studies primarily dealt with the replacement of the fibers concerning ductility, load bearing behaviour and durability by the application of a micro-reinforcement. Within this paper the development of a design concept for micro-reinforced UHPC is presented. Based on experimental investigations, main findings are transformed into analytical expressions, idealized and afterwards implemented into a design concept.