Demolition wastes may be used in different civil engineering applications as road constructions, concrete, and embankments or landfill. Regardless its application, leaching tests of the waste should be carried out to assess concentrations of pollutants. Concrete, brick and mixture of concrete, bricks, tiles and ceramics wastes were subject to percolation test-CEN/TS 14405, and batch test-SR EN 12457. The leachates were analyzed with respect to concentration of inorganic elements-arsenic, barium, cadmium, chromium, copper, mercury, molybdenum, nickel, lead, selenium, zinc, fluoride, chloride and sulfate, and organic compounds (phenol index). The concentrations of elements in leachates were compared with the limit values of European regulation for the acceptance of inert wastes at landfills. Generally, the releases of inorganic species in leachates were below limits values. Some waste leachates obtained by percolation and batch test had high values for phenol index.

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In industrial practice, the dimensional characterization of the polygranular materials can be done, experimentally and/or by calculation, on the basis of various types of granulometric distribution laws, of the different types of diameters, of the specific surface and of some indicators related to the granulometric uniformity. This paper aims at introducing a new indicator, called granulometric uniformity degree, defined on the basis of some informational statistics elements, and calculated in a unique way, different from any particular type of granulometric distribution. At the same time, a series of correlations between the granulometric uniformity degree and different characteristic diameters is pointed out, i.e. the specific surface of cements, characterized by the Rosin-Rammler-Sperling ganulometric distribution.

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Abstract:The cement based grouts, as functional performance composite materials, are widely used for both immobilisation and encapsulation as well as for stabilization in the field of inorganic waste management. Also, to ensure that low level radioactive waste (LLW) are contained for storage and ultimate disposal, they are encapsulated or immobilized in monolithic waste forms, with cement -based grouts. The paper includes some research data referring to cement based grout mix design for use as encapsulating/immobilizing system for low level radioactive waste. The work includes cementbased-grout mix design method used practically into establishing of the optimum grout mix based on the water/cement ratio, cement/sand ratio in order to achieve application requiered values of fluidity, segregation resistance, shrinkage and mechanical strengths. These engineering grout characteristics present relevance for simulation experiments of radionuclide leaching from LLWcement grout encapsulation system.