The objectives of this study were to investigate and analyze traffic accidents involving trucks and to study the relationship between heavy loads and truck braking efficiency. Field tests were made to determine the effect of increased loads on the ability of a truck to brake to a stop and determine if the trucks could meet the requirements of the Federal Motor Carrier Safety Regulations. The test combination truck with a gross weight of up to 151,180 was able to meet both braking distance and maximum G requirements. The test single-unit truck failed to meet requirements only at the maximum weight tested of 120,680 pounds.

Accident data were analyzed for the three-year period of 1994 through 1996. Characteristics of truck accidents were compared to all accidents. A detailed analysis was conducted for all fatal accidents involving a truck. Average and critical numbers and rates of truck accidents were calculated and one-mile sections having a critical rate were located with an investigation conducted at a sample of these sections.

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The contents of this report reflect the views of the authors, who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky, the Kentucky Transportation Cabinet, or the Federal Highway Administration. This report does not constitute a standard, specification, or regulation.