The structural design of fibre reinforced concrete (FRC) elements is largely based on the post-cracking residual strength behaviour provided by the reinforcement. Other aspects such as early age crack control or fire resistance are considered non-structural FRC properties. As far as structural implications are concerned, a minimum mechanical performance of FRC must be guaranteed. Fibres can be employed to improve the behaviour at the Service Limit State (SLS) since they can reduce crack spacing and crack width and hence improve a concrete’s dura- bility. Also, fibres can be used to improve the behaviour of a concrete at its Ultimate Limit State (ULS) where they can either partially or totally substitute conventional reinforcement.The mechanical properties of a cementitious matrix are modified when fibres are added. However, the elastic properties and compressive strength of a given concrete are not significantly affected by fibres unless a substantial percentage of this material is added.
NV Bekaert SA
8550 Zwevegem, Belgium