Time Harmonic Analysis of Concrete Gravity Dam-Reservoir Systems by Wavenumber-TD Approach

摘要

In recent years the Wavenumber approach has been introduced which may be envisaged as a great substitute for the rigorous type of analysis. The former technique is formulated in the context of pure finite element programming, while the latter relies heavily on a two-dimensional semi-infinite fluid element. However, both methods are carried out in frequency domain. Thus, the Wavenumber technique in its original form may be more accurately designated as the Wavenumher-FD approach. In the present study, a variation of the Wavenumber method is proposed, which is referred to as the Wavenumber-TD approach. The approximation to the original technique improves its realm of application and allows it to be carried out in time domain as well as frequency domain. It is also illustrated that two other well-known truncation boundary alternatives (i.e, Sommerfeld and Sharon conditions) may be considered as special cases of the Wavenumber-TD truncation boundary condition. The method is initially described. Subsequently, the response of an idealized triangular dam-reservoir system is obtained by this approach and its special cases for tone harmonic horizontal excitation. All results for the various cases considered are compared against the exact response for models with different values of normalized reservoir length and reservoir base absorptive conditions.