BOND OF REBARS TO STEEL FIBRE REINFORCED CONCRETE: MINIMUM CONCRETE COVER REQUIREMENTS TO PREVENT SPLITTING

Autores UPV
Año
CONGRESO BOND OF REBARS TO STEEL FIBRE REINFORCED CONCRETE: MINIMUM CONCRETE COVER REQUIREMENTS TO PREVENT SPLITTING

Abstract

Steel fibre reinforced concrete (SFRC) is increasingly used in structural elements, where the contribution of fibres to the structural performance is taken into account in their design. Bond of reinforcing bars to concrete is one of the aspects affected by fibres. Fibres enhance bond performance in terms of bond strength and toughness. As higher bond stresses develop, additional effective confinement is needed to avoid splitting failures. This research deals with the confinement required to prevent splitting bond failures in SFRC. In particular, fibres are considered as a of passive confinement together with concrete cover and transverse reinforcement. A series of prismatic specimens have been subjected to the Pull Out Test. Semi-empirical equations have been developed to predict the risk of splitting to the aforementioned factors, with a margin of error less than 5%, which makes it suitable for predictive and modelling purposes. It has been proven that increasing fibre content restrains the risk of splitting failure. The favorable effect of fibres when preventing splitting failures has been revealed to be more important for higher concrete compressive strength values. Two charts based on contour plots have been developed to quickly determine the minimum concrete cover.