Rehabilitation of the Sayano-Shushenskaya HPS dam-foundation system

摘要

After the Sayano-Shushenskaya dam reservoir impounding, the tension cracks appeared on the upstream face of the dam, and the seal failure of the foundation took place at the base of the upstream face. The seepage through the concrete and the foundation amounted to 520 and 5491/s, correspondingly. The lack of the bottom outlets impeded to drop down the reservoir level, therefore, the restoration of the impermeability should be carried out by the head more than 200m. The high rate of leakage did not permit to use traditional mortars for injections. The new repair technology using epoxy grouting was developed. Special attention was paid to the compound composition, control of injection pressure, and injection sequence to avoid inadmissible deformations of the dam body and rock mass. As a result, the seepage through dam's body and rock foundation was decreased up to 99.5% and 78%, correspondingly.