Data compiled for most accident reporting systems are typically the result of police accident investigations. Usually police officers have neither the time nor the experience to conduct in-depth accident investigations or collect the necessary data, when trucks are involved, that will allow examination of the relationships between trucks and the roadway environment. When accidents involve multiple deaths or numerous injuries, special police agencies or accident investigation teams may devote the resources necessary to examine truck-roadway environment relationships. This paper examines microscopic data, including specific accident investigations, to determine problem areas and to identify vehicle characteristics. Then macroscopic studies and nationwide accident statistics are analyzed to define the potential scope of vehicle-roadway environment-related problems, with emphasis on trucks.
This paper examines truck accidents involving runaways, intersections, grade crossings, pavement roughness, barrier, overturns, and wet pavement. Specifically, on steep or long downgrades, trucks run away when improperly maintained or operated. At intersections, minimum clearance times may be insufficient and acceleration lanes are often too short. The Federal Railroad Administration data indicate that 31 percent of grade crossing accidents involve trucks. Truck problems at grade crossings include visibility, audibility, low clearance, and insufficient time to clear the tracks. Rough pavement can cause vehicle parts to break, resulting in uncontrollable trucks that may test roadside barriers to the fullest. On curves, high center-of-gravity trucks tend to turn over at or near the posted or advisory speed. Truck accidents on wet pavement tend to be statistically slightly overrepresented. Trucks tend to jackknife more often when the pavement is wet and recent research has disproven a myth-trucks can hydroplane when empty. On wet pavement, roughness decreased vehicle -tire pavement contact even further, especially on surfaces that are marginal.