Page 503 - New Trends in Eco efficient and Recycled Concrete

Meso-structural modelling in 15

recycled aggregate concrete

1
3
C. Medina 1,2 ,J.Sa ´nchez , I.F. Sa ´ez del Bosque , M. Frı´as 2,4
and M.I. Sa ´nchez de Rojas 2,4
1
Department of Construction, School of Engineering, Graduate degreee in Civil
Engineering, University of Extremadura (UEx), Institute for Sustainable Regional
2
Development (INTERRA), Ca ´ceres, Spain, UEX-CSIC Partnering “SOSMAT”, Ca ´ceres,
3
Spain, Department of Prestacional Development of Concretes, Structural, Reliability and
Risk Analysis, Eduardo Torroja Institute for Construction Science, Spanish National
4
Research Council (CSIC), Ca ´ceres, Spain, Department of Cements and Recycling of
Materials, Spanish National Research Council (CSIC), Madrid, Spain

15.1 Introduction

Today’s sustainable development policies, along with the Paris Agreement to
combat climate change, call for combining economic growth with sustainability
and environmental protection. They advocate replacing the linear
‘take make use throw away’ economy with a circular economy that maintains
the value of resources for as long as possible and reduces the waste generated
(‘zero waste’) when structures reach the end of their service lives.
Against that socio-economic backdrop, concern has arisen around industrial
waste and more specifically construction and demolition waste (CDW), 500 Mt of
which, accounting for 30% to 35% of the total volume, were generated in 2014 in
the European Union (EU) (Aid et al., 2014).
The 46% mean valorisation rate of such waste in the EU masks considerable dis-
parity among the member states. While rates are over 90% in countries with a long
tradition of CDW recycling, such as Belgium and the Netherlands and rising in
England and France, they are much lower in Spain (,17%) and Portugal (B5%)
(European Commission, 2011).
CDW is highly variable, comprising primarily stone-like materials (concrete,
unbound aggregate, ceramic material and asphalt) along with metals and floating
particles. Its treatment yields a heterogeneous recycled aggregate classified in Spain
into five major categories. (1) Recycled concrete aggregate contains $ 90 wt% con-
crete plus natural stone (with no bound mortar). (2) In mixed recycled concrete
aggregate, the concrete and stone content is ,90 wt% and the ceramic material
content ,30 wt%. (3) Mixed ceramic aggregate contains .30 wt% ceramic materi-
als. (4) Ceramic aggregate consists in .70 wt% of such materials. (5) In recycled
aggregate with asphalt the bitumen content is from 5% to 30% (GERD, 2012).

New Trends in Eco-efficient and Recycled Concrete. DOI: https://doi.org/10.1016/B978-0-08-102480-5.00015-4
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