Environmental Benefits ofGreenConcrete

Oftheapproximately 11million tonnes ofannual solid concrete anddemolition waste(CD onlyavery small portion oftheconcrete wasteisreused inbuilding construction. Considering thefact that usable natural aggregate (NA) supplies arediminishing, there will beahighdemandforrecycled concrete aggregates (RCA)tobeusedinthesocalled green concrete (GC). Using recycled concrete asaggregate will helpreduce thetotal costofconcrete production because aggregates neednotbehauled fromremote locations, butobtained locally. Thecombination ofRCAwith significant quantities offlyashorslagasreplacement forPortland cementisparticularly attractive frombotheconomic andenvironmental perspectives. GC will reduce thedemandfornatural resources, theassociated energy consumption, andgreenhousegas (GHG)emissions required toproduce aggregates andcement. Thesereductions canbeconsidered asoneoftheconstruction industry's majorcontributions to Canada'sGHG emissionreduction objective. Althoughthereare some guidelines/specifications established bydifferent countries suchastheUKandJapan, currently, there arenoestablished guidelines forproducing GCinCanada. This paperpresents theenvironmental andeconomic benefits ofincreasing theuseof GCintheconstruction industry andhighlights theobjectives ofanongoing research bytheauthors onGC. Keywords:Recycled concrete aggregates (RCA), greenconcrete, greenhousegas(GHG), aggregate recycling