Seven experiment designs addressing problems of safety and capacity on two-lane rural highways. Volume VII: experimental design to develop and evaluate measures for reducing the effects of roadside friction on traffic flow.

The objective of the experiment is to develop and evaluate the relative merit of warning signs and other devices, used singly or in combination, in improving traffic flow and safety in the presence of a variety of different types of roadside friction elements. The following types of friction elements are considered: vehicles entering the main roadway from driveways, parked or disabled vehicles on the side of the road, combinations of the above to test the effects of friction element density per unit length of road, and bicycle traffic adjacent to the main roadway. As a result of the State-of-the-Art Study, a variety of devices and systems are proposed.