ABSTRACT
The maximum ash percentage was fixed at 25% due to the fact that a higher percentage would cause difficulty in attaining the target strength of approximately 30 MPa at seven days even with the rapid hardening (Type III) cement used. The other mixes contained 0% and 15% replacement fly ash so that a range of comparative results could be obtained. The sand used was a plaster sand (<600µm), once again to minimise the scale effects.
