Yes, there appear to be options to stop or control ASR in some dams !
Résumé
In cases where the ASR continues, given the very long required service life of dams, a hundred years and more, there is a clear need to seek to identify some practical solutions to limit the ASR and its effects in these long-term cases. In such cases the roles of the key ingredients to the reactions, silica, alkalis and water must be clearly understood.
Recent simulations by the authors have shown that, given the increasingly long required service lives of dams, and often the slow rate of expansion, some very long-term solutions, such as draining and drying the concrete to reduce the expansion rates in some parts of dams and associated structures, may be possible and worth considering in some cases. This paper reviews the issues involved in such notions and suggests some scenarios and technical solutions where very long-term sealing, draining and drying may be effective in existing dams with continuing ASR. In addition, we note that in some extreme cases of new dams or rehabilitation of existing dams where there is persistent uncertainty in performance testing of mix designs for ASR prevention, consideration could be given to applying such techniques immediately as a backup in case ASR occurs despite the testing.
We suggest some practical options to achieve these objectives and identify issues that would need to be addressed to confirm their feasibility and practicability.