ASR in mortars or concretes made with composite cements

4 ASR in mortars or concretes made with composite cements The relations between expansion and the content and particle size of the 

Kollek el al. (K68) extended the parallel studies on expansion and pore solution compositions mentioned in Section 12.4.2 to mortars containing pfa, slag or natural pozzolanas. For each mix, several contents of the 

The alkali cations in pfa normally occur almost entirely in the glass, and when the latter reacts may be presumed to enter the alkali-rich silicate that appears to be the initial product. When this phase is decomposed by reaction with Ca, they will be distributed, like alkali cations from any other source, between the solution and the solid hydration products, on which they are probably adsorbed (Section 7.3.2). The C-S-H tends to take them up more strongly as its Ca/Si ratio decreases (BI58,G63) consequently, the alkali cations released from the pfa are less effective in raising the OH concentration of the pore solution than are those released from the cement. The method outlined in Section 7.5.2 for calculating the OH concentration in the pore solution of Portland cement mix was extended to cover Portland-pfa cement mixes taking this into account (T37). 

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