Use of Acceleration-Deceleration Lanes

On the basis of various and recent research studies, it is apparent that highway designers must become more concerned with the relation­ ship between highway design and traffic behavior. An excellent example of current interest in highway design is the design of acceleration and deceleration lanes. In order to obtain maximum efficiency and safety in the operation of acceleration and deceleration lanes, as well as for the main facility, it is necessary to relate the design of these special lanes to the requirements and desires of drivers. Drivers leaving a highway at an interchange usually need to reduce speed when leaving. On the other hand, drivers entering a highway at an intersection need to ac­ celerate in order to reach the desired speed of the traffic on the main facility. Whenever this deceleration or acceleration by exiting or enter­ ing traffic takes place on the traveled way of the main highway, it dis­ rupts the smooth flow of the through traffic and is hazardous. Thus, in order to minimize undesirable friction, maximum use should be made of acceleration and deceleration lanes.