Monitoring seepage flows through the body and foundation of the concrete dam at the Krasnoyarsk hydroelectric plant

Abstract

1. The permeability of the body and foundation of the Krasnoyarsk dam is completely satisfactory at the present time. 2. Separation of flows that enter into the insepection galleries of the dam due to individual forms of seepage (contraction joints, concrete, foundation) made it possible toevaluate the condition of each component of the structure, isolate its sections with the greatest permeability, and to take the necessary measures at the appropriate time. 3. The new seal design for the contraction joints and the application of a grouting method for strengthening the tectonic-crushing zones in the foundation were found to be effective, and can be recommended for future use. 4. The extreme values obtained for the seepage flow, and also the relationships used to determine the magnitude of chemical suffusion in the upstream face and grout curtain of the foundation make it possible to monitor the state of the dam while in service. 5. The experience gained with observations at the Krasnoyarsk dam demonstrated that with a large number of control points, estimated to be in the hundreds, the existing methods of measuring seepage become unproductive and rather unreliable. There is a definite need to develop and implement modern portable devices and remote systems for the automatic measurement of local and overall seepage flows in hydraulic structures.