Standards Development

Scope

This document describes the analytical procedures used to determine the content of C3A in the clinker starting from a chemical analysis on cement. The method can be applied to CEM type I and IV for the determination of the requirement of C3A, as defined on EN 197 1.

This document describes two methods, traditional wet and XRF analysis (EN 196 2), which can be considered to be equivalent, in the scope of this CEN/TR 17365, for the determination of Al2O3, Fe2O3 and SO3.

The same methods are described in EN 196 2, but for the scope of this document, the X-ray fluorescence (XRF) is the preferred method to be used for the determination of Al2O3, Fe2O3 and SO3.

Purpose

WG 15 has created a TG1 (4 meetings) to evaluate a proposals for developping a new project related to XRD method for the determination of C3A in the clinker from cement.

21 laboratories have joined the test campaign.

During the discussion of TG1, it was decided to organize interlaboratory tests on standard samples.

In the meeting of July 2022, the results of RRT was discussed and:

The average value of C3A from all the labs involved is very close to the true value, both for high C3A clinker and for low C3A clinker, both for CEM I and for CEM IV.

The determination of mineralogical composition in cements is influenced by the Rietveld analysis more than by sample preparation or instrumental equipment.

In order to improve the accuracy of its own result, each lab should:

- Improve the number of structures used for the refinement, including the different polymorphs;

- For pozzolanic cement, improve/uniform the determination of crystalline phase;

- For CEM IV, improve/uniform the determination of amorphous phase

Next meeting 1°Q 2023. The date of the next meeting has been postponed to 2°Q 2023.

Right now we are preparing the samples for a new IPT that will start in 3°Q 2023.