Car-pool restrictions will apply during rush hours to Shirley Highway express lanes between the Pentagon and Washington. A story yesterday incorrectly said that the restrictions were being removed on that section at all hours.

The Shirley Highway express lanes are scheduled to open today to all motorists during nonrush hours.

The lanes, between Springfield and Washington, will continue to be limited to four-member car pools during the 6-to-9 a.m. and 3:30-to-6 p.m. weekday rush hours.

The express lanes, built in 1969, are being opened for a one-year trial imposed by Congress. At the urging of Rep. Stan Parris (R-8th District), Congress declared that the lanes were underused most of the time and urged a test of easing the restrictions.

Built in the center of I-395, the lanes are reversible and are open to northbound traffic from 11 p.m. to 11 a.m. and to southbound traffic from 11 a.m. to 11 p.m. Highway officials say the lanes may be reversed as late as two hours behind schedule in the coming weeks because the gates onto the express lanes must be opened and closed manually.

The procedure will change in late April or early May when a $23 million computerized traffic system goes into operation and entrances to the express lanes will be closed electronically.

The express lanes initially were restricted to buses and were planned as a temporary measure by Virginia; but they were opened to car pools in 1973, and since then they have become an accepted part of highway planning in the state. Officials are considering building similiar lanes in the Norfolk-Virginia Beach area to resolve traffic problems there.

Pentagon commuters especially will benefit from the new regulations because the Pentagon has two direct access ramps to the expess lanes at Eads Street. After today, Virginia highway officials said, motorists going to or from the Pentagon any time can use the express lanes leading into Washington and ignore the car pool regulations.