Assessment of Safety and Operation Performances of CFIs and DDIs in Utah [Research Brief]

Details

• Creators:
  Song, Yu (Fred) ; Zlatkovic, Milan ; Dhimal, Ramesh ; Neupane, Kiran
• Corporate Creators:
  University of Wyoming ; Upper Great Plains Transportation Institute
• Corporate Contributors:
  United States. Department of Transportation. University Transportation Centers (UTC) Program ; United States. Department of Transportation. Office of the Assistant Secretary for Research and Technology
• Subject/TRT Terms:
  Bayes' Theorem Calibration Continuous Flow Intersection Countermeasures Crash Data Diamond Interchanges Diverging Diamond Interchange Empirical Methods Evaluation And Assessment Extreme Value Theory Performance Surrogate Safety Measures

  More +
• Publication/ Report Number:
  CTIPS-26-004
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Utah
• Edition:
  Research Brief
• Corporate Publisher:
  Center for Transformative Infrastructure Preservation and Sustainability (CTIPS) Region 8 University Transportation Center (UTC)
• Abstract:
  This research provides a comprehensive evaluation of the operational and safety performance of diverging diamond interchanges and continuous flow intersections under Utah-specific conditions by employing a dual-framework methodology that analyzes 16 years of historical crash and traffic data (2006-2021). To address the limitations of isolated assessment methods, the first component utilizes safety-integrated microscopic traffic simulation via multimodal traffic simulation software, where surrogate safety measures-time-to-collision and maximum deceleration-were extracted and translated into predicted crash frequencies. The second component features a crash-based empirical evaluation to develop locally calibrated safety performance functions (an indicator of expected changes in crashes after implementing a countermeasure) and generate highly reliable, Utah-specific crash modification factors for fatal-and-injury crashes and property-damage-only crashes. By integrating surrogate safety analysis with rigorous empirical evaluation, this research equips transportation agencies with a transferable, data-driven framework to proactively assess both the efficiency and safety of innovative geometric intersection designs.
• Format:
  PDF
• Funding:
  CTIPS-014
• Collection(s):
  University Transportation Centers
• Main Document Checksum:
  urn:sha-512:75958e6c305b9d71f9413cbcd9e72298f7def0732a974a45811aa0e0c84969fabe68734cbf179cca921f27b6578224cd98b3ee68076e9fa782bef5cd310f739e
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/92900/dot_92900_DS1.pdf
• File Type:
  [PDF - 482.48 KB ]