Untersuchungen an Sand-Zement-Agglomeraten zum Einsatz als grobe Gesteinskörnung in Beton (English shop)

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In northern Germany, an area lacking naturally occurring coarse aggregate, this aggregate required for concrete production is either obtained by screening the local gravel deposits (coarse aggregate content approx. 20 %) or imported, for example as chippings from Scandinavia. Instead of using the surplus sands for subordinate backfilling tasks, they can be formed into larger agglomerates by adding binder using established granulation processes and can then be used like normal coarse aggregate in concrete. The sand agglomerates have a lower particle strength than natural aggregate, but are more durable than the matrix of conventional concretes. They can be used to produce durable normal concrete that complies with the established design rules and does not exhibit the usual weaknesses of a “sand concrete”.

The energy expenditure and plant requirements involved in producing the granulates are offset by the technical extraction effort and the savings in transporting coarse aggregate over long distances.

In investigating the influence of various sands and binder quantities on the properties of the agglomerates, the research demonstrated that the sands occurring in the region are suitable for the process across a wide range of particle size distributions. In order to control the production process and monitor the quality of the hardened agglomerates, force-deformation curves were determined for a large number of fresh and hardened individual particles and examined for their suitability as control and quality parameters.