Cyclic loading – future use and storage

In the future, an increased cyclical loading of embankment dams is expected due to new operating modes of hydropower plants as a result of the transition to a fossil-free energy system. This project investigates the effects on dams caused by cyclical loading, where the water surface is regulated faster than before.

Settlement is not a new issue, but new operational modes expose dams to a new loading condition for which they were not originally designed. This project is expected to identify dam types where the new loading condition may be critical. Throughout the project, different types of dams will be analyzed, as the response is expected to vary depending on factors such as structure (zoning) and height.

The project focuses on water saturation, pore pressure, and alarm thresholds to support risk management efforts. Laboratory tests on materials from dams are planned to identify the properties of the materials used in the dam structure. During drawdowns, areas with remaining pore pressure will exist within the dam body, and unsaturated conditions will prevail in certain zones. To describe this behavior, knowledge of the materials’ retention capacity is needed. The project will also focus on cyclic triaxial tests to gain more information on how dam materials respond to rapidly fluctuating water levels. To evaluate future effects on the dam body, numerical modeling will be used. Conditions favorable for particle migration and internal erosion may potentially be identified.