Frank O. Gehry, the avant-garde architect chosen to build an addition to the Corcoran Gallery of Art in the heart of official Washington, said yesterday that his design would address the sensibilities of the city.

"I think Washington represents a challenge, and this is one I haven't really had in my life--to be right in the center of the capital and all the issues that attend to making a building here," said Gehry, 70.

At a news conference, Corcoran President David C. Levy officially introduced the architect, who will design a new wing for the museum, the city's oldest art gallery. The wing will house the museum's art school.

The two men stood near a model of the museum complex on 17th Street NW, with its two landmark buildings that look directly at the White House. Gehry's preliminary concept for the addition--what he grumpily called a "sketch"--is a floating tower of bent wings, flying over the 100-year-old classical roof of the original building and billowing onto the sidewalk of New York Avenue.

The Corcoran assignment gives Washington a chance to see the work of one of the world's daring architects up close. Gehry's recent work has drawn lavish praise, as well as controversy. His Guggenheim Museum Bilbao in Spain, a riverside building that looks like an unfolding flower, initially stunned the public, but the structure is now considered one of the most important of the last 25 years.

Washington has a reputation as a conservative arts city with stodgy architecture, but the official landscape has slowly adjusted to contemporary designs.

The Hirshhorn Museum and Sculpture Garden on the Mall and the Vietnam Veterans Memorial not far from the classical Lincoln Memorial were considered out of sync initially but have become admired parts of the city's fabric. In the 1940s, the plan for a Frank Lloyd Wright apartment building on Connecticut Avenue was quashed because it was considered radical.

Gregory K. Hunt, dean of the architecture school at Catholic University, sees the Corcoran's choice of Gehry to design the new wing as a chance to compensate for that mistake and some ugly sightlines.

"This is terrific," Hunt said. "This city has been less than enthusiastic about forward-thinking work. And one thing to consider above all is this is an art school. The public doesn't expect [art students] to be doing Renaissance art behind the walls."

Gehry stressed that his creative process, and the eventual design, will be the result of a thoughtful collaboration. "It is not just a souffle we put together in 15 minutes just to upset Washington," he said. "It is a really important building that has to be dealt with, a really important mission that has to be dealt with and has a really important opportunity, and that excites me."

The Corcoran chose Gehry from an initial field of 200.

"Frank Gehry has taken public architecture in a new and brilliantly original direction," Levy said. "In the end, it was Gehry's stunning originality coupled with his deep respect for the Corcoran's historic building . . . that tipped the balance." After an estimated year of planning, construction is expected to begin in 2001.

The Corcoran is not government-owned, but the Gehry design must be approved by the city's Commission of Fine Arts. So far, officials there are enthusiastic.

"It is marvelous that we are getting one of the best practitioners of architecture in the world doing a building in Washington in that location," said Charles Atherton, the commission's secretary.

CAPTION: The architect: Frank Gehry promises that his Corcoran Gallery addition will be right at home in Washington.

CAPTION: His work: Gehry's Guggenheim Museum in Bilbao, Spain, was initially controversial but now is widely praised.

CAPTION: In a model of the Corcoran complex, the billowy curves of Gehry's new wing are a take on the curve of the original gallery next door.