Arthur Samberg, the founder of Pequot Capital Management Inc., and Mario Gabelli, chairman of Gamco Investors Inc., pledged a combined $40 million to Columbia Business School to help fund a new campus.

Samberg will donate $25 million and Gabelli will give $15 million, according to an e-mailed statement from the school in New York. Samberg and Gabelli both graduated from Columbia Business School in 1967.

The new business school facility is expected to cost about $600 million, of which $500 million has been raised, said Christopher Cashman, a spokesman. Scheduled to open in 2018, it will be part of Columbia University’s Manhattanville complex in upper Manhattan. Henry Kravis, co-founder of private equity firm KKR & Co., and Ron Perelman, billionaire investor in Revlon and other companies, have each donated $100 million to the school and will have buildings named after them.

“I am extraordinarily grateful to accept these generous pledges,” Glenn Hubbard, dean of the business school, said in the statement. “Thanks to their support, our new Manhattanville campus will feature classrooms of tomorrow and other cutting- edge innovations.”

Part of the 17-acre Manhattanville campus, located about 10 blocks north of Columbia’s Morningside Heights base, is scheduled to open in 2016 with a nine-story science center. Mortimer Zuckerman, chairman of Boston Properties Inc., pledged $200 million to endow a center for neuroscience research which will be located there.