[en] As part of Sandia National Laboratories' Severe Accident Sequence Analysis (SASA) Program, structural analyses of the Watts Bar, Maine Yankee, and Bellefonte containment structures were performed with the obtective of obtaining realistic estimates of their ultimate static pressure capacities. The Watts Bar investigation included analyses of the containment shell, equipment hatch, anchorage systems, and personnel lock. The ultimate pressure capability is estimated to be between 120 and 137 psig, corresponding to shell yielding and equipment hatch buckling, respectively. The Maine yankee investigation consisted of an analysis of the containment shell and estimated its failure pressure to be between 96 and 118 psig. For the Bellefonte containment, analyses of the containment shell and equipment hatch were performed. The pressure capacity of the Bellefonte containment is estimated to be between 130 and 139 psig, corresponding to dome tendon yielding and cylinder wall tendon yielding, respectively