When supporters of the Chazen Museum of Art set out to nearly double the building?s size with a $43 million addition, a key goal was to seamlessly unite the museum?s existing structure with a new building via a bridge. Now, the aim is to build a stronger bridge from UW-Madison?s vastly expanded home for art to the larger Madison community. The Chazen opens its doors at noon Saturday to celebrate its enhanced presence on University Avenue with an open house, entertainment and tours of the 86,000-square-foot addition.