Long-term monitoring of earth dam of the Charvak hydroelectric power plant (HPP) considering the water level of the reservoir

A numerical method for determining the settlement and stress-strain state (SSS) of high earth dam of the Charvak hydroelectric power plant is developed based on the finite element method (FEM). The results were compared with the available data from long-term field observations and with records of continuous geodetic monitoring of the dam behavior based on processed space radar images obtained from the Sentinel-1 satellite. To conduct calculations, OJSC Gidroproekt of the Republic of Uzbekistan provided the structural and piecewise non-homogeneous physical and mechanical characteristics of soil of the structure body. The results of calculations of vertical displacements, normal stresses, and pore pressure were compared with field observation data for the section in which the corresponding control and measuring equipment was installed. A cause-and-effect relationship was identified between the water level in the reservoir and the deformation of the dam. The difference between the theoretical results obtained and field observations was up to 10%. A comparison of the results obtained using the finite element analysis calculations (taking into account the level of water filling in the reservoir) with the actually measured deformations of the dam during the filling of the reservoir, and with processed space monitoring data depending on the time of year, showed a good agreement between the measured and calculated displacements.