This study was conducted to determine the differences in performance between 102-in. (259-cm) wide and 96-in. (244-cm) wide trucks and the impact that these trucks have on other traffic. Trucks which were studied primarily included random trucks in the traffic stream, although a limited amount of control truck data were also collected to account for driver differences. Truck data were collected on rural two-lane and multilane roads which included curve and tangent sections and a variety of roadway widths and traffic conditions. The data collection effort resulted in approximately 100 hours of videotape and 9,000 slides from which various measures of effectiveness (MOEs) were extracted. A number of MOEs were used to test for the operational effects of differential truck widths, lengths, and configurations. Such measures included: (1) lateral placement of the truck and the opposing or passing vehicle, (2) lane encroachments by the truck or opposing vehicle, and (3) edgeline encroachments by the truck or opposing vehicle.

This synthesis report will be of interest to officials and staff of municipal, regional, and statewide transportation agencies responsible for roadway design and traffic control. It will be of special interest to those concerned with intersections and driveways on divided highways where larger vehicles encounter narrow medians. It will also be of interest to other professionals who interact with these agencies to mitigate such problems. This report presents state-of-the-practice information about current median design policies and practices, describes the traffic operational and safety problems encountered in designing for larger vehicles at divided highway intersections, and identifies alternative improvement techniques that can be used in new construction or reconstruction projects to avoid introducing traffic operational and safety problems. This TRB report focuses on 10 alternative cross sections widely used on arterial highways in urban, suburban, and rural environment.