Interactions structure-eau sous l'effet des séismes, masses ajoutées, et effets 3D: Application à une vanne radiale

«Structures in direct contact with a fluid are subject to structure-water interaction and hydrodynamic pressures generated under seismic excitation. These additional pressures increase the loads applied to the structure, thereby raising the risk of failure. This is why many researchers strive to develop accurate models of structure-water interaction to design such structures effectively. However, the modeling and analysis of structure-water interaction effects on complex 3D interfaces, such as radial gates, remain relatively undocumented. A commonly used method to represent this phenomenon is the fluid finite element method, renowned for its high precision. Nevertheless, this approach has notable drawbacks: it is complex to implement, requires specific training, and involves significant computational time. In industry, an alternative method often preferred is Westergaard’s added mass method, initially developed for modeling rigid 2D dams. However, its application to curved, three-dimensional structures can be challenging and pose technical difficulties. This thesis aims to develop a new practical method for applying Westergaard’s added mass method to complex structures. Initially, a new practical method for applying the added mass approach was developed. A study was then conducted to examine different ways of integrating Westergaard’s method into 3D models, including planar and radial interfaces. The results showed that for coarse models, the method of applying the added mass had a significant influence on the outcomes. Subsequently, a parametric analysis was carried out to investigate the effects of the geometry of the structure-water interface. This analysis highlighted the importance of the three-dimensional characteristics of the geometry on the dynamic response of a structure in contact with a reservoir.»