Development of Analytic Method to Determine Weaving Patterns for Safety Analysis near Freeway Interchanges with Access Management Treatments Grant uri icon


  • This project supports a student in support of National Cooperative Highway Research Program (NCHRP) Project 07-23 Access Management in the Vicinity of Interchanges. This research will use a large volume of operational field data, micro-simulation data, and crash data to identify linkages between interchange design, driveway placement, and upstream major intersection location that affect corridor safety. This effort will primarily focus on the diamond interchange configuration that is very common in the United States. The methods for determining corridor safety near interchanges can create challenges. Due to the large traffic volumes, varying travel times, widely varying geometric features of the interchange, and a variety of access management scenarios, it is a challenge to assess the data and determine if safety performance issues should be attributed to the interchange traffic, the driveway traffic, the upstream intersection traffic, or a combination of these operational features blended with the prevailing corridor geometrics. These unknown issues make improving safety at these locations a challenge. For this research effort, the student will use field collected travel time and volume information to develop validated micro-simulation models that depict actual site conditions. Each location will then undergo a safety assessment to identify what factors appear to be correlated with safety performance. These "base" models will then be modified to change access management techniques (add or change medians, increase or decrease access density, shorten or lengthen distance to nearest major intersection) and then assess how minor changes may influence the operational performance. Though safety cannot be directly extracted from this micro-simulation activity, performance measures attributed to safety for the "base" models will be identified and evaluated using a sensitivity analysis for the resulting large volume of data. The student funded by Safe-D is working with data collected for NCHRP project 07-23 but she is providing an added value by developing a method for determining vehicle weaving patterns in these interchange regions. This activity goes beyond the scope of the NCHRP project but builds upon it. The student´┐Żs work requires data mining using simulation data, video data, and travel time data (in some cases all merged together).

date/time interval

  • 2017