PD CEN/TR 16142:2011

Foreword
Summary
1 Introduction
Part I
2 Scope of the study
3 The experimental precision and its
   implications
4 Standardisation of the characterisation leaching
   method
5 Conclusions
6 Appendices
7 References
Part II (informative) - TEST METHOD USED IN
        THE STUDY FOR CHARACTERISATION OF
        LEACHING
1 Scope
2 Normative references
3 Terms, definitions, symbols and abbreviations
4 Materials and reagents
5 Apparatus
6 Determining the leaching behaviour
7 Calculation of cumulative leaching and expression
   of results
8 Precision of cumulative leaching
9 Characterising the leaching behaviour
10 Test report
Annex A (normative) - Determination of the available
        (potential) amount of a component
        for leaching
Annex B (normative) - Determination of the surface
        area (A) of a test piece (PD) for use in
        the diffusion (tank) test
Annex C (informative) - Diagrammatic representation
        of the diffusion (tank) leaching
        procedure
Annex D (informative) - Supplementary procedures for
        calculating the indicative upper limit for
        leaching for particular characteristics of
        the leaching behaviour
Bibliography

Provides a method for characterising the time-dependent leaching behaviour of components from hardened concrete, for use in the natural environment.

This Technical Report describes a method for characterising the time-dependent leaching behaviour of components from hardened concrete, for use in the natural environment.

This method specifies the procedures for determining the controlling mechanism(s) for leaching of components, their effective diffusion coefficients, in the case of diffusion-control and their cumulative release behaviour over any period of time.

This characterisation method consists of two leaching test procedures. A potential or availability (pulverised specimen) test and a diffusion (tank) [monolithic specimen] test.

The test procedures produce leachates, the analytical procedures for which are not included in this Technical Report.

This Technical Report does not comprise a compliance method.

NOTE 1 The information obtained from the method is quantitative. In the absence, however, of similar information for other construction materials or compliance criteria for acceptable/unacceptable performance of hardened concrete, the data obtained with neither permit a relative nor an absolute assessment of the environmental quality/compatibility of the concrete, unless, by default, in the case where leached concentrations of environmentally significant components are at, or below, their analytical limits of detection.

NOTE 2 In principle, this method could be used to characterise the leaching behaviour of hardened concrete, irrespective of the exposure conditions (e.g. natural environment, contact with drinking water etc.) which the concrete would experience in service. It should be noted, however, that a European standard test method for the extraction/migration of mineral micropollutants is also likely to be developed by CEN/TC 164 - Water supply.

NOTE 3 Analytical procedures for determining concentrations of components in leachates and which may be suitable for the purposes of this Technical Report are being developed by CEN/TC 292 - Characterization of waste and CEN/TC 230 - Water analysis.