In the TMI accident, the reactor vessel itself remained largely intact, maintaining its major containment function, although the liner and part of the carbon steel shell sustained damage due to interactions with melted core material. The reactor pressure vessel was not perforated, but significant melting and chemical reactions occurred at the baffle and core support plate. Some fuel elements did disintegrate, with the upper portions exposed and damaged, but the vessel was not completely emptied of water. Fuel particles fell to the bottom of the reactor pressure vessel, interacting with the stainless-steel liner. Overall, while there was substantial damage within the core, the reactor vessel's integrity was preserved.