Моніторинг сезонних вертикальних зміщень греблі Дніпровської ГЕС

Abstract

The relationship Methods. A program developed for this purpose processed a time series of GNSS measurements, which allows for determining vertical seasonal displacements and their dependence on seasonal changes in ambient air temperature. Results. A review of scientific works on the temperature field impact on the deformation of hydraulic structures is presented. Based on the studies performed, it was found that in the absence of sharp drops in the water level in the upper reservoir, seasonal changes in ambient temperature have a significant impact on the vertical displacements of dams (in the example of the Dnipro HPP). The magnitude of extreme displacements and the epochs of their manifestation will depend on the dam design and technical parameters. Based on the processed data, a linear relationship was established between the average ambient temperature and the vertical displacements of GNSS control points located at the Dnipro HPP dam, which makes it possible to predict the value of vertical displacements of control points based on the measured temperature value. Accordingly, monitoring these displacements and their changes over time is one of the criteria for assessing the overall condition of the dam. We noticed that during the study period, the extremely positive average rate of the vertical displacements of the control points was in the first half of 2018, +1.03 mm per month, and the extremely negative average rate of 0.83 mm/month was in the second half of 2019. It explained the correlation between the vertical displacement rate of the control point and the depth of the reservoir near it. Scientific novelty and practical significance. The regularities of the relationship between temperature changes and GNSS point displacements revealed in the study can be useful for further research on the processing and analysis of monitoring data for hydraulic structures.