Full-scale observations of dam of the Hoabinh hydraulic development during construction period

1. The observations and installed control-measurement instruments on the whole ensured the required control conditions for the rock-earth dam of the Hoabinh hydraulic development and the carrying out of analyses of its state. 2. An analysis of the structure behavior performed using data from instrumental observations showed that the stress-strain conditions of the dam are favorable and correspond to the requirements intended to ensure its reliable operation. The development and distribution of the stress-strain conditions of the dam conform to the design assumptions. Earthquakes in the hydraulic-development region did not affect the process of development of the measurable deformations. 3. The results of observations of the seepage regime of the dam and the base indicate normal operating conditions. The hydraulic gradients on the curtain and the base do not exceed the allowable values. The antifiltration curtain effectiveness is uniform along the front and is stable with time. 4. An analysis of the full-scale observation results performed when construction of the structure was completed showed that the dam body settlements are in the attenuation phase, that the pore pressure dissipation process has been practically completed, and that the parameters of seepage flow in the dam and the base are below the allowable values. The structure state indices permit giving an optimistic prediction of reliability of the dam under rise of the reservoir water elevation to the NPL.