Improving cracking behaviour with recycled steel fibres targeting specific applications - analysis according to fib Model Code 2010

Abstract

A new and appealing mean of improving the cracking behaviour of RC elements is the combined use of rebars and fibres. Previous research has shown that steel fibres recycled from end-of-life tyres are effective for this purpose. This paper presents and discusses practical applications that would benefit from the use of this technique. Firstly, two previously published examples of crack width calculation according to fib Model Code 2010 are expanded to the case under study. These practical applications show how a fibre-reinforced concrete (FRC) with a rather poor post-peak behaviour can exhibit large improvements in cracking behaviour while being economically attractive, too. The case of jointless structures is then considered, and the improvements in terms of maximum achievable length are presented and discussed. Finally, an analysis regarding the effectiveness of this solution as a function of the reinforcement ratio is discussed for both tension and bending. The main objective of this paper is to encourage the use of recycled steel fibres as an effective and sustainable mean of dealing with cracking behaviour for specific applications. K E Y W O R D Scracking, FRC, recycled steel fibres, fib Model Code 2010, integral structures

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