The Cleveland Museum of Art will unveil a major expansion plan this week, as designed by architect Rafael Viñoly, whose proposal “calls for demolishing nearly half of the museum’s existing complex before rebuilding and expanding the museum’s “footprint” and gallery space.” The renovation will cost $225 million and is scheduled to be completed in 2008. But the museum will have to delay the project if it cannot raise at least half of the money by the end of next year.