OPERATIONAL EVALUATION OF TRUCK RESTRICTIONS ON I-20 IN TEXAS

With the increased expansion of highways to six lanes, questions have arisen as to the proper operational strategy of those facilities. One strategy gaining support is to restrict large vehicles from one or more lanes. The effects of such restrictions, however, had not been extensively studied. The operational effects of a truck restriction on I-20 near Fort Worth, Texas, were analyzed. Vehicle distributions according to classification, vehicle speeds, and time gaps between vehicles were examined to evaluate the operational effectiveness of this left-lane truck restriction. No analysis or evaluation of accident rates or pavement wear was undertaken. Although the directional distribution of trucks changed significantly because of the restriction, no effects were found that could be attributed to the truck restriction in the directional distribution of cars, speeds of either cars or trucks, or time gaps between vehicles.