A semi‐analytical method for time‐domain analyses of dam–reservoir interactions

Non‐linear responses of dam–reservoir systems are not well understood, because of the lack of an exact time‐domain solution for the far field (extending to infinity) of the fluid. This paper presents a procedure for efficient time‐domain analyses. It is based on a semi‐analytical solution and is suitable for the determination of the interactive behaviour of dam–reservoir systems. In this formulation, the fluid domain is divided into a near (to the dam) field, which is finite, and a far field extending to infinity. Arbitrary shapes of the upstream face of the dam, and of the bottom of the reservoir floor in the near field, are presumed. Furthermore, the far field is assumed to have a constant depth. The irregular near field is modelled by using the finite element method. A time‐domain semi‐analytical solution is obtained for the far field. For a vertical dam subjected to earthquake and ramp loadings, numerical solutions obtained compared well with the piecewise exact form of the analytical solution.