Large dams are grand structures with a complex nonlinear dynamic behavior. These nonlinear effects, though relatively small, can be very important for the analysis of dam mesoscopic damage accumulation using available monitoring data, namely, the time series of strains/tilts of the dam structure in response to the periodic filling/draining process of the reservoir. The authors derive the characteristics of the unknown dynamics using the time series of tilts and strains of a structure by means of recurrence plots (RPs), recurrence quantification analysis (RQA), Lempel-Ziv complexity (LZC), mutual information (MI), detrended fluctuation analysis (DFA), and singular spectrum analysis (SSA) for studying dam dynamics. Anomalies in the nonlinear dynamics characteristics of the measured time series of the tilts/strains of dam during the reservoir regular filling/discharge process may signal the abnormal behavior of the object. These methods were used for the analysis of the monitoring data of the 271-m-high Enguri arch dam, still one of the highest (in its class) dams in the world, which was built in the canyon of Enguri river (West Georgia) in the 1970s. Since 1996, the European Centre “Geodynamical Hazards of High Dams” of the Council of Europe has been operating on Enguri dam. Since 2020, the International Project DAMAST: Dams and Seismicity has been going on in the Enguri dam area.
Part of the book: Special Topics in Dam Engineering