DEVICE FOR PREVENTING A NUCLEAR REACTOR CORE FROM PENETRATING THE GROUND AFTER MELT-DOWN

摘要

Device for preventing a nuclear reactor core from penetrating the ground after melt-down, said reactor being supported by a concrete raft resting on the ground, whereby a restraint tank (6) of refractory material is inserted in the concrete raft (4). The upper part (10) of the tank (6) in contact with the core is made of a refractory material inert to the constituents of the said core. The lower part (8) of the tank (6) is made of a refractory material having a thermal conductivity at least equal to 15 times that of the upper part (10). The upper part (10) of the restraint tank (6) is preferably made of zirconium, 2 to 10 cm thick, and the lower part (8) is made of graphite. The device may also have means (5) for deflecting lateral irradiation of the concrete raft.