3D numerical simulation of the hydrodynamic behavior of dam-reservoir-intake towers under earthquake and landslide effects

Water compressibility significantly influences the earthquake-induced hydrodynamic response of dam-reservoir systems. Recent earthquakes have highlighted that surface waves overtopping the dam crest remain a serious risk for high-head dams due to energy considerations. Consequently, a comprehensive numerical model is essential for assessing the risk to large dam-reservoirs during earthquakes, considering key effects such as compressibility, turbulence, bottom absorption, and breaking surface waves. This study presents a three-dimensional numerical model using OpenFOAM libraries for the simulation of dam-reservoirs subjected to harmonic and real earthquake excitations. Volume of Fluid (VOF) method is used to simulate surface waves. Validation with theoretical results shows that the proposed model can be reliably used for seismic risk assessment of high dams. The validated model is applied to simulate the hydrodynamic behavior of the Aşağı Kaleköy dam-reservoir system under earthquake loading, emphasizing the importance of compressibility. On the other hand, landslide is another important factor that influences hydrodynamic response of dam-reservoirs during earthquake. Therefore, the present numerical model has been extended to simulate landslide, focus on deformable landslide. using the Herschel–Bulkley rheological, which accurately describes characteristic behavior. Numerical results validated with the experimental data, showing good agreement in wave height, and landslide deformation. The model is implemented to the Aşağı Kaleköy dam, non-immersed and partially immersed sliding masses are simulated. Numerical simulations demonstrate that non- immersed case resulted in higher hydrodynamic force. The last chapter of this thesis reports numerical analysis of hydrodynamic response of the tower intake within the Aşağı Kaleköy dam reservoir. A parametric analysis is performed to investigate length of the zone effected by the seismic effects. Based on a series of numerical simulations, an empirical equation is proposed for the estimation of the effective length. The validated numerical model is then employed for the simulation of landslide-induced surface waves through the tower tank.