Photos of cars on freeway, speeding sign

Freeway Management and Operations Handbook

Description of Figure 8-14: Moveable Barrier Technology

This drawing shows a highway with two lanes in each direction and cars in each lane. A barrier is shown between the oncoming lanes, with the caption "T-shaped concrete barriers are connected by specially designed hinges and heavy steel pins to form a continuous moveable barrier".

A bus-like transfer machine is shown with an opening that rides over the barrier. The caption for the transfer machine states "The machine is guided automatically by a computerized guidance system that reads a signal form a cable buried in the roadway".