ABSTRACT
Figures 5 and 6 show a reduction in sorptivity with increasing age and with decreasing water/cement for the control specimens, as expected. There is some remaining ambiguity in the results but it can be seen that pure silane is better than dilute silane, particularly for the higher water/cement. For good concrete, it seems that there is not much advantage in applying the second coat of pure silane. The acrylic containing treatments are seen to perform well here too but we cannot be sure if this is because of the acrylic or not. It is certain, however, that the silane or siloxane part will contribute a lot to the water resistance in these cases. The observations from Figures 5 and 6 are of most relevance when the protection required is against salt ingress in solution in water.
