Geometric Design Strategic Research Program

1. Geometric Design Strategic Research Program Transportation Research Board AFB10 Geometric Design Committee Brian L. Ray, PE Committee Chair July 27, 2010

2. What have we heard so far? • Freight design criteria • Complete Streets • 2015 Green Book Topics • Highway Safety Manual • Flexibility in preliminary Engineering • Right sized projects • Urban street design standards • Practical Design • Others?

3. What will be the basis of our design decisions? RESEARCH!

4. Presentation Outline • Overview of the TRB Geometric Design Committee • Geometric Design Strategic Research • Opportunities for Collaboration

5. Committee Scope Expanding the body of knowledge regarding highway and street geometric design elements that affect safe and efficient operations for all users. Developing research needs statements and communicating findings that advance geometric design criteria, guidance, methods, and performance-based design objectives. Facilitating domestic and international dialogues and idea exchanges while supporting emerging and developing professionals

7. Committee Structure • Research Subcommittee purpose • Coordinate and manage the strategic research program • Produce the research needs statements using the input from others

8. Committee Structure • Technical Subcommittee purpose • Conduct activities that lead our exploration of technical issues and priorities. • Subgroups: • Streets and Intersections; • Highways; • Freeways and Interchanges; and • Methodology

9. Committee Structure • Business Subcommittee purpose • Execute reoccurring and ad-hoc committee business • Conduct outreach to external sources in support of committee business, • Coordinate special assignments and forums as they arise

10. AASHTO Members • Jim Brewer/Kansas • Bart Thrasher/Virginia

11. Presentation Outline • Overview of the TRB Geometric Design Committee • Geometric Design Strategic Research • Opportunities for Collaboration

12. Current Research Needs Documentation http://onlinepubs.trb.org/onlinepubs/circulars/ec110.pdf Transportation E-Circular (E-C110) 22 research needs statements

13. Research Needs Development Process TRB Committees on Geometric Design (AFB10) & Operational Effects of Geometrics (AHB65) & AASHTO Technical Committee on Geometric Design “Re-thinking” Design Process Design Controls/Criteria User/Vehicle Controls Rural Highways Freeways/Interchanges Urban Streets Intersections

14. “Original” Research Needs

15. Funded Synthesis Statements Topic 40-07: Trade-off Considerations in Highway Geometric Design Topic 40-08: Effective Speed Reduction Techniques for Rural High to Low Speed Transitions Topic 41-01: Geometric Design Practices for Resurfacing, Restoration, and Rehabilitation

16. UPDATING STRATEGIC RESEARCH NEEDSJuly 2009 Mid-year meeting

17. Process • Form four technical subgroups: • Methodology • Highways • Freeways and Interchanges • Streets and Intersections • Review and update existing white papers • Review and update unfunded research needs statements • Identify emerging topics

18. PRIORITIZED RESEARCH NEEDS AFB10/AHB65

19. Methodology/Design Controls Critical assessment of geometric design policies and practices Safety effects of intersection sight distance Updating decision sight distance criteria Applying geometric design criteria in intermediate speed range Forgiving roadside design (coordinate with AFB20) Bicycle safety prediction methodology

20. Highways *Developed and considered by AASHTO Safety evaluation of 13 controlling criteria* Study of vehicle paths on horizontal curve transitions* Speed prediction models for multilane rural/suburban highways Speed prediction models for trucks Relationship between safety, roadway lighting, and geometric design features AFB10/AHB65

21. Freeways and Interchanges *Developed and considered by AASHTO Integrated Ramp and Ramp Terminal Design* Multilane Loop Ramp Design* Allocation of Freeway Lane and Shoulder Widths AFB10/AHB65

22. Streets and Intersections *Developed and considered by AASHTO Auxiliary Turn Lane Design Guidance and Policy Upgrades* Safety effects and implementation of intersection skew angles Intersection design and evaluation guidebook Comprehensive roadway design for complete streets AFB10/AHB65

23. Synthesis Topics Design and maintenance of traffic during construction Curve and cross-section design on temporary facilities Truck facility design (marshaling yards, truck-only ramps) Highway design to support traffic enforcement Barrier toll plaza vs. open-road tolling design Current practices for provision of sidewalks Vertical pavement profiles at intersections Crosswalk cross-slope design practices AFB10/AHB65

24. “Updated” Research Program

25. Presentation Outline • Overview of the TRB Geometric Design Committee • Geometric Design Strategic Research • Opportunities for Collaboration

26. In general… Support the effort to update Transportation Research E-circular Provide input and support on existing and new research needs statements and synthesis topics Share ideas on Green Book revision and other research needs

27. 2010 and 2011… • Share results of Green Book needs discussion from this SCOD meeting • Obtain input from 2010 Green Book update effort • Identify other emerging needs • Plan for the joint Mid-year 2011 meeting with TRB and AASHTO Technical Committee on Geometric Design

28. Questions? Interested? Contact: Brian Ray Kittelson & Associates, Inc. bray@kittelson.com