Method for analysing the quantity of clay in a sand

A method for determining the quantity of superplasticizer-intercalating clay in a sand, comprising the following steps:

• a) Providing a composition (C) comprising a compound of formula (I)
• R1—(OA)n-XR2 (I)
• where:
• R1 is a linear or branched C1 to C4 alkyl group, or a coloured compound:
• R2 is a coloured compound;
• A, each the same or different, are independently a —CH2—CH2— group or —CH(CH3)—CH2— group;
• n is an integer of between 1 and 500:
• X is O or NH;
• b) Taking a sample of the sand to be analysed;
• c) Mixing composition (C) with the sand sample in a container and agitating;
• d) Filtering the mixture obtained at step c);
• e) Determining the concentration of superplasticizer-intercalating clays in the sand as a function of the colour of the solution obtained at step d).

A method for determining the amount of Clay Mitigation Agent CMA to be added to a sand suitable for use thereof in a hydraulic binder composition, comprising the following steps:

• i) Providing a composition (C);
• ii) Taking a sample of sand to be analysed;
• iii) Mixing composition (C) with the sand sample in a container and agitating;
• iv) Filtering the mixture obtained at step iii);
• v) Determining the amount of CMA to be added as a function of the colour of the solution obtained at step iv);
• wherein composition (C) comprises a compound of formula (I)
• R1—(OA)n-XR2 (I)
• where:
• R1 is a linear or branched C1 to C4 alkyl group, or a coloured compound;
• R2 is a coloured compound;
• A, each the same or different, are independently a —CH2—CH2— group or —CH(CH3)—CH2— group;
• n is an integer of between 1 and 500:
• X is O or NH.