Large dam-reservoir systems: guidelines and tools to estimate loads resulting from natural hazards

Abstract

This paper examines hydrodynamic pressure diagrams due to earthquakes acting on distinct configurations of the upstream face of a dam, considering the reservoir length and different bathymetries of the reservoir bottom. Two suitable mathematical models are used to obtain the dynamic pressure on the dam, and the reservoir free surface oscillation. Conceptual mathematical models are proposed to study the impact of a landslide triggered by an earthquake, and its progress into the reservoir. The waves formed when a landslide advances into the reservoir are tested with the help of laboratory results. These waves and their propagation in the reservoir are studied using experimental data and numerical results, including wave-type analyses based on dimensionless parameters. Two distinct 1DH and 2DV numerical models based on different mathematical formulations are tested. A discussion of physical and numerical results is detailed in a general risk context and uncertainty associated with the input data in a deterministic model. Numerical simulations are performed for the upper and lower limits of the sliding mass velocity diagram which is obtained as a result of the intrinsic uncertainty of the stochastic nature of the friction angle. Finally, the findings are discussed and some conclusions drawn.