Spatial and Temporal Analyses of Crashes at Two Work Zones with Different Traffic Control Devices: Barrels and Jersey Barriers

Work zone safety is one of the highest priorities for traffic engineers. In order to guide the motorists safely and efficiently through the activity areas of work zones, construction types and
work procedures must be studied in advance to select and install appropriate traffic control devices. Traffic engineers will benefit in evaluating cost effectiveness of installing certain types of traffic control devices if any relationships can be identified between traffic control devices and work zone crashes. Two case study work zones with different main traffic control devices (barrels and New Jersey barriers) were selected and their crash records were analyzed in detail, along with the five-mile sections both upstream and downstream of the activity areas, using the crash records available from the Utah Department of Transportation. One of the study sites was located on a rural US route and the other on a rural interstate. The former study site used barrels and the latter used concrete Jersey barriers as their main traffic control devices. It was found that the transition area upstream of the activity area was most crash prone than the activity area itself, regardless of the types of main traffic control devices used in the activity areas of the work zones. Inside the activity area, the entry and exit ends were found to be most crash prone at both study sites. Notable differences were not found in the crash occurrence patterns at these study sites.