Shirley Highway. That's the Virginia freeway where Los Angeles-style traffic jams are commonplace in rush hours. But who ever heard of jams when the rush hour is over?

They're happening every night now on Shirley -- otherwise known as I-395 -- from 7:30 p.m. to 5:30 a.m. State highway officials have closed off all but one southbound lane of a 2 1/2-mile segment just inside the Capital Beltway so the adjacent two lanes can be repaved with a nonskid surface. Backups of a mile or more are commonplace.

But, as motorists sit bumper-to-bumper waiting to make it through the squeeze, two "express" lanes that are available to southbound rush-hour car pools up to 7:30 p.m. -- and which could be opened to the squeeze victims after that hour -- are blocked off.

John W. Chiles, the Virginia Department of Highways and Transportation's resident engineer for maintenance, dismissed the idea of opening the express lanes. He said it would be confusing to alter the normal arrangements for their use, which is northbound in the morning rush hour and southbound in the evening rush hour. "It's confusing enough as it is," he said. "We don't want people to get into that."

Meantime, Virginia's busiest road -- 109,700 cars use Shirley each day in the construction area between Edsall Road and the Beltway -- remains a bottleneck until next week at the earliest.