DIN EN 1097-1:2011-04

This European Standard specifies the reference method used for type testing and in case of dispute for determining the resistance to wear of coarse aggregates (main text) and aggregates for railway ballast (Annex A). For other purposes, in particular factory production control, other methods may be used provided that an appropriate working relationship with the reference method has been established. The sample is normally tested in a wet condition, but the test may also be carried out in a dry condition. This European Standard applies to natural, manufactured or recycled aggregates used in building or civil engineering. The test determines the micro-Deval coefficient which is the percentage of the original sample reduced to a size smaller than 1,6 mm during rolling. The test consists of measuring the wear produced by friction between the aggregates and an abrasive charge in a rotating drum under defined conditions. When rolling is complete, the percentage retained on a 1,6 mm sieve is used to calculate the micro-Deval coefficient. The test method described in this European Standard is the reference method and is carried out with dry aggregate with the addition of water to give a value of MDE. Annex B gives details of how the test can be performed without the addition of water, to give a value of M_DS. The document EN 1097-1:2010 has been prepared by Technical Committee CEN/TC 154 "Aggregates", the secretariat of which is held by the BSI (United Kingdom). The responsible national Committee is Working Committee NA 062-03-13 AA, Mirror Committee of CEN/TC 154 "Aggregates" of the Materials Testing Standards Committee (NMP). The following amendments have been made with respect to DIN EN 1097-1:2003-12: a) scope has been extended to railway ballast (Annex A); b) new normative Annex A "Determination of micro-Deval coefficient in the dry condition" has been incorporated.