It is understood that this is a broken part of a wall. Alternate translation: "like a broken part of a wall that is ready to fall" (See: [[rc://en/ta/man/translate/figs-ellipsis]])
This can be reworded so that the abstract noun "fall" is expressed as the verb "fall." Alternate translation: "that will suddenly fall" (See: [[rc://en/ta/man/translate/figs-abstractnouns]])