RecyMblock - application of recycled mixed aggregates in the manufacture of concrete construction blocks

摘要

With an annual production of 10 million tonnes, construction and demolition waste is one of the most important wastestreams in Flanders, Belgium. 95% of this construction and demolition waste (CD&W) is processed into recycledaggregates. The amount of recycled concrete aggregates and the amount of mixed aggregates are about the same. InFlanders, Belgium there is a well developed recycling industry for CD&W, with more than 165 recycling companies on fixedlocations and 44 certified mobile installations, most of which are SMEs. Recycled aggregates have evaluated towards aworthy alternative for natural aggregates. Their use should be looked at from a point of chain management and economicuse of natural mineral. Therefore more applications with added value should be found for this kind of recycled aggregatesthat usually end up in low grade applications. This is the case for mixed recycled aggregates. Whilst a lot of research isdone on using recycled concrete aggregates, less research is performed to find high grade applications for the use ofmixed recycled aggregates. This paper shows that it is possible to produce an industrial competitive product. Mixedrecycled aggregates (MRA) were used as a replacement of natural aggregates in the production of hollow and full concreteblocks. The aim of this research was to produce construction blocks with a high level of MRA with a quality similar to thestandard products on the market. Up to 95% of MRA was used in the production of full concrete construction blocks andup to 75% in hollow concrete construction blocks. As a result of this research, 3500 hollow building bricks were producesin an existing building block manufacturing company. These blocks were used as an example in the “Centrum DuurzaamBouwen “ (Centre of Sustainable Building) in Heusden-Zolder. This case proved the high added value of MRA in theproduction of building blocks.