Abstract
The objective of this study is to understand the timing of truck and car accidents in a busy freight corridor (I-110 and I-710 freeways) that connects the Ports of Los Angeles and Long Beach to nearby intermodal rail and trans-loading facilities, and various warehouses. The authors analyze 16,417 accidents that occurred between 2005 and 2007 on these two freeways in Los Angeles County, California; approximately 14.5 percent of these accidents involved trucks. Vehicle Miles Traveled (VMT) data were collected from the Freeway Performance Measurement System (PeMS) to compute hourly and monthly car and truck accident rates for both freeways in both traffic directions. Kolmogorov-Smirnov and CramÃrâ??von Mises goodness of fit tests were then calculated to test whether directional accident probabilities are similar or not and whether the risk of an accident is time dependent. The authors found that the probability of an accident involving only cars is highest after midnight (the peak probability occurs between 1 AM and 3 AM for both freeways) while the probability of an accident involving a truck is highest during mid-day (the peak probability occurs between 8 AM and 4 PM for both freeways). These results have implications for programs that attempt to move truck deliveries during off-peak hours such as the PierPass program implemented by the Ports of Los Angeles and Long Beach..