Design earthquakes for ITER in Europe at Cadarache

摘要

The European site proposed for ITER is situated in the south of France, 40 km north-east of Aix-en-Provence, in a low to moderate seismic area according to the Global Seismic Hazard Map (GSHAP Group 1999). The tokamak building would be implemented on good bedrock made of limestone with a shear wave velocity of over 1300 m/s. Input requirements and assumptions for ITER consider that an infrequent, severe earthquake (called SL-2), although unlikely to occur during the lifetime of the facility, is assessed to demonstrate adequate protection of the public. This earthquake is assumed to have a return period of 10,000 years. An investment protection level or inspection level (where all structures, systems and components are safe) with a peak ground acceleration (pga) at 0.5 m/s~2 is also considered. As a basis, orders of magnitude of consequences, if no countermeasures were taken, are given. Four aspects are discussed: regulation, implementation of this regulation for the proposed site (site geology, tectonic and seis-motectonic), a probabilistic seismic hazard assessment of the site and finally, the fulfilment of the requirements and assumptions, according to IAEA guides. As a conclusion of the studies, the main characteristics of the Cadarache European site are discussed. Preliminary studies have shown that the European site proposal will ensure a low level of project risk with respect to the seismic hazard.