Within the operation of research recycling and alternative materials of the Laboratoire Central des Ponts et Chaussees, a study was carried out by the Laboratoire Regional des Ponts et Chaussees de Saint-Brieuc to evaluate the relevance of available leaching behaviour tests to simulate the release of polluting elements resulting from a waste used in a road scenario. The main parameters likely to bring closer the conditions of the up-flow percolation test (CEN/TS 14405) of more specific conditions of a road scenario were evaluated. The liquid : solid ratio and the level of initial compaction of the sample showed a small influence on the polluting element release of the studied waste (polluted gravel concrete). According to the results of the experimentation of the instrumented road RD 767 (capping layermade up of municipal solid waste incinerator ash), the test of percolation in its standardized standard version (with L/S day = 0.5) constitutes a relevant test to simulate the kinetics of at least short-term release (L/Scumulated < 2) of metallic elements (Cu, Pb). A more important experienceon instrumented sites will be necessary to evaluate the relevance of thistype of method for an approach "middle to long term" release. For the longer term release approach, the more easily accessible leaching test (NF X31- 210/IN 12457-2) gives results close to the results obtained by the percolation test. This compliance test should not thus inevitably be rejected for a simulation of release, at least in a road scenario. For the coveringabstract see ITRD E139491.
Abstract