Proportioning of Steel Fibre Reinforced Concrete Mixes for Pavement Construction and Their Impact on Environment and Cost

Abstract

Steel fibre reinforced concrete (SFRC) is a construction material investigated for more than 40 years including for pavement applications. A number of studies have demonstrated the technical merits of SFRC pavements over conventional concrete pavements; however little work has been carried out on the environmental and economical impact of SFRC during the pavement's life cycle. Therefore, extended research was undertaken within the framework of the EU funded project -EcoLanes‖ to estimate the environmental and economical loadings of SFRC pavements. The innovative concept of the project is the use of recycled steel tyre-cord wire as concrete fibre reinforcement, which provides additional environmental benefits for tyre recycling over landfilling. Within the project framework a demonstration of a steel-fibre-reinforced roller-compacted concrete (SFR-RCC) pavement was constructed in a rural area in Cyprus. In order to assess the economical and environmental picture of the demonstration pavement, life cycle cost analysis (LCCA) and life cycle assessment (LCA) studies were undertaken, which also compared the under study pavement design with four conventional alternatives. The main OPEN ACCESSSustainability 2011, 3 966 output of the studies is that SFR-RCC is more environmentally and economically sustainable than others. In addition, various concrete mix designs were investigated by considering parameters such as fibre type and dosage, cement type, and transportation distances to the construction site. Fibre dosage has been highlighted as a crucial factor compared with economical and environmental loadings in SFR-RCC pavement construction.

Positive Interaction of Industrial and Recycled Steel Fibres in Fibre Reinforced Concrete

“…that it has an adequate energy absorption and good residual strength after cracking (Aiello et al 2009). If more recycled steel fibres are added to the mixture, the postpeak flexural behaviour is similar to that of the ordinary fibre reinforced concrete (mixture with 2% industrial and 6% recycled steel fibres by weight are comparable) (Achilleos et al 2011;Neocleous et al 2011).…”

“…Previous research in this field mainly consisted in the study of fibre reinforced concrete properties and focused exclusively on recycled steel fibres, and comparison with steel fibre reinforced concrete containing industrial steel fibres (Achilleos et al 2011;Aiello et al 2009;Graeff et al 2009;Neocleous et al 2006;Tlemat et al 2004). Recent studies (Graeff et al 2012) on fatigue resistance of concrete pavements reinforced with recycled steel fibres suggests that for enhanced fatigue performance a combination of recycled and industrially produced fibres would be ideal.…”

The effect of shrinkage cracks on the load bearing capacity of steel-fibre-reinforced roller-compacted-concrete pavements

“…Ecolanes (2006)(2007)(2008)(2009), an EU funded research project, developed optimised processes for roller-compacted SFRC (SFR-RCC) to produce long lasting pavement infrastructure for surface transport, utilising recycled-tyre-steel-fibres (RTSF) (Neocleous et al 2006;Achilleos et al 2011;Neocleous et al 2011;Graeff et al 2012;Jafarifar 2012;Jafarifar et al 2014). …”

The Use of Steel Cord Scrap in Concrete

“…The characteristics of the plasticizer were as follows: resin concentration in the solution -36.1 %, pH value -5.05; electric conductivity -1.480 mS/cm, solution density -1040 kg/m 3 . The recommended content of the superplasticizer is 0.2 % to 2.5 %.…”

“…With the growing demand for innovative recycling technologies and sustainable buildings some researchers propose to use crumb rubber and steel cord reclaimed from endof-life tires in the designing of concrete mixes [3].…”