The 101st Congress convened Tuesday with leaders of the Democratic-controlled chambers pledging cooperation with a George Bush White House, but with tensions already mounting within the Capitol over a proposed hefty pay raise for lawmakers.

President-elect Bush, acting in his role as vice president, presided over the Senate session and then immediately administered the oath of office to the new and re-elected senators in groups of four.The Senate chamber was outfitted with new gold curtains behind the presiding officer's chair and new carpet throughout. There were new benches upholstered in bright scarlet for staff members. "It's all for television," said Sen. Carl Levin, D-Mich., showing off the accommodations to constituents.

The galleries were packed with spectators, including Lady Byrd Johnson, widow of the late president and mother-in-law of Virginia's new Democratic Sen. Chuck Robb.

In the packed House chamber, also recarpeted for the new session, the 433 members were called to the chamber to be sworn in en masse. There are two vacancies in the House.

Democrats hold strong majorities in both chambers, 55-45 in the Senate and 259-174 in the House. Tuesday, there was talk of cooperation with Bush from leaders of both parties.

"We're very optimistic that we're going to be able to work with (President-elect) Bush and we can solve some of the problems," said Rep. Tony Coelho, D-Calif., House majority whip. "We need to have that cooperation. We'd like to resolve some problems and get rid of some of this confrontation."

"I think at least at the outset the appropriate tone is one of cooperation and a spirit of bipartisanship, and let's see how far we can go with that," said Rep. Dick Cheney, R-Wyo., House minority whip.

Moving to get a jump on other lawmakers, Rep. Tom Tauke, R-Iowa, announced a bill to force roll-call votes before Congress accepts any pay increase, and delay any approved raise two years - until after the next election. Under current law, Congress automatically gets a boost proposed by the president unless it votes it down.

"Congressional pay adjustments have become a perpetual source of debate, controversy and embarrassment," Tauke said.

President Reagan is expected to call for a substantial pay raise next week for members of Congress to take effect March 1 unless rejected before then by both houses. An advisory commission has recommended a 50 percent boost for lawmakers, federal judges, and top executive branch officials, with members of Congress giving up lucrative honorariums in exchange.

Current congressional pay is $89,500 a year, and the commission's proposal would raise it to $135,000.

"If the president goes ahead and proposes a pay raise we're prepared to go ahead and eliminate the honorariums," Coelho said.

While the Democratic-controlled Congress awaits Reagan's proposal on the pay issue, on most of the nation's biggest issues it's waiting for the new president-elect to make his positions known.