Seismic design of the ITER main Tokamak components

In order to assess the structural performance of the ITER Main Components it is important to take into account not only the mutual dynamic interaction among them during a seismic event but also their interactions with the Tokamak Buildings (TB) complex. The seismic behavior of the TB is affected by the large dimensions of the building, the concrete basemat thickness that has to be sufficiently rigid to support the weight of the Tokamak, the presence of anti-seismic bearing (ASB) under the basemat, and the distribution of heavy equipment at higher levels. These factors require that the soil–structural interaction must be studied in detail, taking into account the specific effects such as the excavation influence and the building rocking motion due to seismic wave propagation. The study of the seismic behavior has been carried out using two different linear dynamic methodologies: power spectral density (PSD) and spectral analyses. The paper illustrates the main results of the seismic analyses and gives the seismic design input for the Tokamak components in terms of support loads, accelerations and displacements.