Standards Development

Scope

This European Technical Report describes procedures for determining the contents of most of the constituents of the cements that fall within the scope of EN 197-1.

In principle, the method described in Clause 6 applies to all cements, whatever the number and nature of their constituents, but in practice is limited to the cements identified in Table 1.

The method in clause 6 should be considered to be the method of choice and is based on a sequential selective dissolution of the cement’s constituents, generally of an unknown number, where they are not available separately for analysis at the same time as the cement.

The method of choice enables the quantitative determination (by mass) of: Portland cement clinker, blastfurnace slag, siliceous fly ash, natural pozzolans, limestone, silica fume and set regulators in cements of the types identified in Table 1. Table 1 is derived from Table 1 of EN 197-1.

NOTE 1 Where cements contain calcareous fly ash, burnt shale and/or constituents that partly contain mineral phases, similar to those of clinker, further investigation into the characteristics of those constituents will be necessary before the method can be applied.

The method of choice has limitations, as indicated earlier, and cannot be considered to be a means by which clinker content can simply be determined in isolation from any other constituent. Clinker content is determined ‘by difference’ and other constituents contain, in part, mineral phases similar to those present in clinker and can cause interferences that lead to difficulties in interpretation of the results.

Where apparently anomalous results are obtained, it is recommended that further investigations are undertaken in accordance with the procedure given in Section 6.2.5.4.

Purpose

The request was made by Belgium and is motivated by the need to be able to quantify the “main constituents” of cement. This request becomes more and more pressing for the certification of composite cements (N355).

In Belgium, calcined clays (Q) are increasingly used as a main constituents in cements. Belgian Certification (Be-Cert) request to standardize the identification and quantification of calcined clay in cements.

A small group of experts, TG4, coordinated by Ms. Vanhamme was created.

The initial objective will be to verify the feasibility of revision of the CEN/TR 196-4 through a literature search and to propose possible alternative methods.