Combustion-induced loads in large-dry PWR containments

The potential for combustion-induced failures of containment must be considered when estimating the risk associated with nuclear power plants. Some large-dry PWR containments are sufficiently strong that it is difficult to envision scenarios in which combustion events alone would challenge their ultimate capacities. On the other hand, the ultimate capacities of other, weaker, large-dry containments are more easily challenged by combustion events. Recently, analyses have been performed to investigate the range of possible containment loadings that could be produced due to combustion events during severe accidents in large-dry PWR containments. Calculations are presented for typical atmospheric and sub-atmospheric containments. Various accident scenarios are examined and key parameters influencing potential combustion-induced loads are identified