NUCLEAR SAFETY OF SPENT FUEL POOL STORAGE AT NUCLEAR POWER PLANTS WITH VVER-1000: PHYSICAL PRINCIPLES AND STRUCTURAL SOLUTIONS

The physical principles and structural solutions concerning nuclear safety in handling nuclear fuel at nuclear power plants with VVER-1000 are examined. It is shown that a structure of storage racks in the holding pools based on the spacing of hexahedral boron steel pipes, the structure acting as a combined neutron trap, will increase the pool capacity as compared with the loosely packed pools and will make the handling of nuclear fuel nuclear safe under normal operating conditions and during accidents. In the future, this construction will make it possible to use fuel assemblies with high uranium content and fuel enrichment above 5%.