Research in Progress (RIP) https://rip.trb.org/ en-us Copyright © 2026. National Academy of Sciences. All rights reserved. http://blogs.law.harvard.edu/tech/rss tris-trb@nas.edu (Bill McLeod) tris-trb@nas.edu (Bill McLeod) Research in Progress (RIP) https://rip.trb.org/Images/PageHeader-wTitle-RIP.jpg https://rip.trb.org/ Evaluation of Alternative Intersection and Interchange Options for Nebraska https://rip.trb.org/View/2689408 Tue, 02 Jun 2026 12:26:34 GMT https://rip.trb.org/View/2689408 Safety and Operational Performance Assessment of CFIs and DDIs in Utah https://rip.trb.org/View/2632836 Thu, 27 Nov 2025 08:54:32 GMT https://rip.trb.org/View/2632836 Evaluating the Economic and Safety Trade-offs of Interchange and Access Drive Separation Distances https://rip.trb.org/View/2627344 Wed, 19 Nov 2025 14:36:56 GMT https://rip.trb.org/View/2627344 Develop a Data-Driven Intersection & Interchange Control Evaluation (DIICE) Tool https://rip.trb.org/View/2614516 Tue, 28 Oct 2025 11:20:20 GMT https://rip.trb.org/View/2614516 Assessment of Safety and Operation Performances of CFIs and DDIs in Utah https://rip.trb.org/View/2394799 Thu, 20 Jun 2024 16:23:48 GMT https://rip.trb.org/View/2394799 A Guide on Alternative Intersections and Interchanges https://rip.trb.org/View/2381742 Wed, 22 May 2024 12:59:54 GMT https://rip.trb.org/View/2381742 Assessing Safety Performance of Atypical Service Interchanges https://rip.trb.org/View/2219016 Tue, 25 Jul 2023 08:09:40 GMT https://rip.trb.org/View/2219016 Guide for Pedestrian and Bicycle Safety at Alternative Intersections and Interchanges (A.I.I.) https://rip.trb.org/View/2166263 Mon, 01 May 2023 17:59:41 GMT https://rip.trb.org/View/2166263 NCHRP Implementation Support Program. Implementation for NCHRP Research Report 948—Guide for Pedestrian and Bicycle Safety at Alternative Intersections and Interchanges https://rip.trb.org/View/1957067 Fri, 27 May 2022 12:50:45 GMT https://rip.trb.org/View/1957067 Guide for Lighting at Innovative Intersections/Interchanges, including Roundabouts https://rip.trb.org/View/1957085 Thu, 26 May 2022 16:53:31 GMT https://rip.trb.org/View/1957085 Groundwork for the Second Edition of the Alternative Intersection and Interchange Informational Report https://rip.trb.org/View/1870698 Thu, 05 Aug 2021 13:05:48 GMT https://rip.trb.org/View/1870698 Developing a Crash Modification Factor for Converting from an At-Grade Intersection to a Diamond Interchange https://rip.trb.org/View/1870697 Thu, 05 Aug 2021 12:55:51 GMT https://rip.trb.org/View/1870697 Innovative intersection and Interchange Designs and Their Use Across the Southeast (Project E4) https://rip.trb.org/View/1843144 Thu, 25 Mar 2021 20:59:41 GMT https://rip.trb.org/View/1843144 SPR-4545: Alternate Interchange Signing Study for Indiana Highways https://rip.trb.org/View/1724241 Tue, 28 Jul 2020 10:34:10 GMT https://rip.trb.org/View/1724241 Wrong-Way Driving Solutions, Policy, and Guidance https://rip.trb.org/View/1513307 Mon, 21 May 2018 21:37:03 GMT https://rip.trb.org/View/1513307