Certification system for aggregates produced from building waste and demolished buildings

Abstract In the Netherlands per annum about 14 million tons of building and demolishing waste are produced. Nowadays about 8 million tons are recycled, mainly for unbound road base courses. This market is almost saturated and a further increase in re-use must be realized within other sections of the building industry. One of these is the use as an aggregate in concrete. However, quality requirements for concrete are more difficult to meet for various reasons. The concrete industry is rather reluctant to accept the material, in the first place because of a lack of confidence in the quality. Another aspect is that the government on the one hand stimulates the re-use for building and demolishing waste as much as possible but on the other hand also fears pollution of the soil if incidentally contaminated building and demolishing waste is applied. This has stimulated the implementation of quality assurance systems by the recycling industry. Initially this industry established its own foundation which carried out attestation of conformity with the requirements of a quality assurance guideline. In 1993 this system has been converted into a certification system which will be approved officially in 1994 by the Dutch Council for Certification. Within the tight quality control scheme of this third-party certification the customers can confidently rely on the quality of this recycling aggregate.