Introduction
The proposed studies on concrete reinforced with recycled steel fibres ( RSF ) represents an additional way to enhance a sustainable development in concrete constructions , which in the last years became one of the most important aims of the concrete users and producers . This fundamental concept , introduced in 1987 by the Brundtland Commission , deals with the “ development which meets the needs of current generations without compromising the ability of future generations to meet their own need ”. An innovative approach to the concrete technology can reduce the amount of raw materials , reusing other by-products , such as crushed aggregates , recycled fibres , etc . Furthermore , the introduction of RSF can reduce the use of traditional steel fibres , with the related amount of energy needed for their production . Using scrap tires ( ST ) also means to reuse and recycle a hazardous waste with all the required special treatments and land disposal . In this context , this manuscript concerns with the application of waste steel as discontinuous reinforcement of concrete matrix . It has been widely deepened that the use of concrete reinforced with steel fibres is particularly suitable in hyperstatic structures , among which the industrial pavements on ballast are a significant example , because the residual strength in the post-cracking phase offered by the fibrous reinforcement increases the overall load bearing capacity of the structure . It is well recognized that the introduction of fibre reinforcement into a concrete matrix modifies the typical brittleness of the plain concrete into a more ductile behaviour , improving its toughness and its post-cracking residual strength ( Olivito et al . 2010 ; Shah et al . 2004 ; Colombo et al 2009 ; Ding 2011 ; Buratti et al . 2011 ). The experimental work is a part of a research project , based on the development and the characterization of fibre reinforced concrete with RSF ( Fig . 1 ).
Figure 1 : Recycled steel fibres from scrap tires
The research project is focused on the assessment of construction technologies with the recycling of materials from ST in concrete . Its final aim is to obtain environmental and ecological benefits as well as a significant reduction in landfilling of the waste tires obtained without losing the properties of the traditional concrete . Based on the results already obtained by the authors ( Aiello et al . 2009 ; Centonze et al . 2012 ), the main issue is to use the steel as reinforcement in concrete matrix obtaining a new material with physical and mechanical properties that can be compared to those of the reference concrete .
Experimental investigation
The mix-design was performed taking into account the results obtained in previous experimental
776 ZEMCH 2015 | International Conference | Bari - Lecce , Italy