Page 113 - New Trends in Eco efficient and Recycled Concrete

Waste rubber aggregates
4

Valeria Corinaldesi and Jacopo Donnini
Department of Materials, Environmental Sciences and Urban Planning, Universita `
Politecnica delle Marche, Ancona, Italy

4.1 Introduction

Waste generation in the European Union was estimated to be over 1.43 billion
tonnes per year and it increases at rates comparable to those of the economic
growth (Martı `nez et al., 2013). Consequently, waste reduction and recycling issues
are fundamental steps in establishing a sustainable approach on waste management.
Waste rubber is a major concern worldwide. In 2005, over 10 billion tyres were
discarded worldwide (Alamo-NoleLuis et al., 2011) and around one billion tyres
are withdrawn from use each year (Colom et al., 2007). By 2030, this number could
reach up to 1200 million tyres being discarded (Pacheco-Torgal et al., 2012). In
2011, it was estimated that, worldwide, approximately four billion waste tyres were
in landfills and stockpiles (World Business Council for Sustainable Development,
2008).
In Europe, 355 million tyres are produced every year, representing 24% of the
world’s production (Presti, 2013). In addition, the European Union has millions of
used tyres that have been illegally dumped or stockpiled. The inadequate disposal
of tyres represents a potential threat to human health (e.g., as a fire risk and haven
for rodents) and increased environmental risk. Most countries have relied on landfill
to dispose used tyres, but the limited space and their potential for reuse has led to
many countries banning this practice.
Most waste tyres are disposed in landfills. However, with the recent introduction
of European Union directives restricting this practice while promoting material and
energy recovery, will result in landfill disposal being drastically reduced in the near
future. The use of innovative techniques to recycle waste tyres is a crucial issue. A
significant proportion of waste tyres are used in civil engineering applications, such
as road and rail foundations and embankments (ETRMA, 2011). Recycled waste
tyres are also used for energy generation in cement kilns (Siddique and Naik,
2004), incinerated for the production of electricity (Oikonomou and Mavridou,
2009), used as an additive to cement-based materials (Del Rio Merino et al., 2007;
Al-Akhras and Smadi, 2004; Benazzouk et al., 2007), as a lightweight filler (Chen
et al., 2013), as crush barriers, bumpers and artificial reefs (Shu and Huang, 2014).

New Trends in Eco-efficient and Recycled Concrete. DOI: https://doi.org/10.1016/B978-0-08-102480-5.00004-X
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