Citation

Stopper DA, Darnell PD, Voeglie CC. Collision 2010; 5(2): 42-47.

Copyright

(Copyright © 2010, Collision Publishing)

DOI

unavailable

PMID

unavailable

Abstract

Reconstruction of many commercial motor vehicle (CMV) incidents and collisions involves developing a supportable time for truck tractor/semi-trailer combinations to execute turns, cross traffic lanes or clear intersections during traffic light sequences. This becomes a more critical issue with the ever-increasing lengths of these combination vehicles, which can now reach 70 ft in length. Calculating the acceleration rate of the combination vehicles can play a critical role in conducting an accurate analysis. This article seeks to develop a statistically significant sampling of loaded and unloaded truck tractor semi-trailer acceleration rates given "best effort" accelerations typical of a combination entering traffic. Tests were conducted using a random selection of CMVs as they passed through a fixed scale weigh station. Drivers were interviewed to obtain information regarding engine manufacturer, horsepower, and transmission type. The selected vehicle was weighted and then drivers were requested to give "best effort" acceleration from a stop until they passed the data collection station. Continuous acceleration data was collected using an acceleration tracking system. A total of 167 acceleration runs were recorded, with vehicles grouped into 7 weight categories. The data indicates that heavy CMVs will typically accelerate more quickly during the beginning of acceleration where applying an average value for a longer distance may not be applicable. The results from the acceleration tests represent a real-world range of values that an accident investigator can apply with a reasonable degree of certainty.