Research Reports
A variety of research studies have been performed using data from HSIS. Many of the final reports prepared are now available electronically. A complete list of available publications is provided below.
Safety Effects of Horizontal Curve and Grade Combinations on Rural Two-Lane Highways
The safety effects of horizontal curves and grades on rural two-lane highways have been quantified in the American Association of State Highway and Transportation Officials (AASHTO) Highway Safety Manual (HSM), but it was not previously known whether and how the safety performance of horizontal curves and grades interact. Furthermore, there are no established safety effects for crest and sag vertical curves, and it is unknown whether and how the safety performance of crest or sag vertical curves is affected by the presence of horizontal curves.
The objective of this study was to quantify the combined safety effects of horizontal curves and grade combinations and express the results as crash modification factors (CMFs) that can be considered for use in the AASHTO HSM.
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Safety Evaluation of Converting Traffic Signals from Incandescent to Light-Emitting Diodes
Across the Nation, many agencies have been replacing conventional incandescent light bulbs in traffic signals with light-emitting diodes (LED). LEDs are primarily installed to reduce energy consumption and decrease maintenance. In addition, LEDs are expected to last much longer compared with incandescent bulbs and tend to age gradually. However, a recent study revealed several potential problems with LEDs, including their inability to melt snow and issues related to visual discomfort caused by glare at night.
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Safety Evaluation Of Discontinuing Late-Night Flash Operations at Signalized Intersections
During late-night flash (LNF) mode (from late night to early morning hours), traffic signals flash yellow for one road (typically, the major road), requiring caution but no stopping, and flash red for the other road (typically, the minor road), requiring drivers to stop and then proceed through the intersection after yielding to the traffic on the major road. The intent of LNF is to reduce energy consumption and delay during periods of low traffic demand. However, in recent years, many agencies have begun replacing LNF with normal phasing operation because of safety concerns.
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Roadside Grading Guidance - Phase I | December | Kevin Schrum, Francisco D.B. Albuquerque, Dean Sicking, Ronald K Faller, and John. D Reid. | |
| NCHRP Web-Only Document 295: Improved Prediction Models for Crash Types and Crash Severities | January | John N. Ivan, Sha Al Mamun, Nalini Ravishanker, Bhagwant Persaud, Craig Lyon, Raghavan Srinivasan, Bo Lan, Sarah Smith, Taha Saleem, Mohamed Abdel-Aty, Jaeyoung Lee, Ahmed Farid, and Jung-Han Wang | |
| NCHRP Web-Only Document 297: Intersection Crash Prediction Methods for the Highway Safety Manual | January | Darren J. Torbic, Daniel J. Cook, Karin M. Bauer, Joseph R. Grotheer, Douglas W. Harwood, Ingrid B. Potts, Richard J. Porter, Jeffrey P. Gooch, Kristin Kersavage, Juan Medina, and Jeffrey Taylor |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Contributing Factors for Focus Crash and Facility Types | November | Taha Saleem, Richard Porter, Raghavan Srinivasan, Daniel Carter, Scott Himes, and Thanh Le | FHWA-HRT-20-052 |
| Rural Speed Safety Project for USDOT Safety Data Initiative | May | Subasish Das, Srinivas Geedipally, Raul Avelar, Lingtao Wu, Kay Fitzpatrick, MohamadrezaBanihashemi, and Dominique Lord | N/A |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Developing Vehicle Occupancy Factors and Percent of Non-Single Occupancy Vehicle Travel | April | Robert Krile, Andrew Landgraf, and Elizabeth Slone | FHWA-PL-18-020 |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Safety Evaluation of Horizontal Curve Realignment on Rural, Two-Lane Roads | April | Raghavan Srinivasan, Daniel Carter, Craig Lyon, and Matthew Albee | FHWA-HRT-17-066 |
| Safety Evaluation of Turning Movement Restrictions at Stop-Controlled Intersections | March | Thanh Le, Frank Gross, Tim Harmon, and Kimberly Eccles | FHWA-HRT-17-064 |
| Safety Evaluation of Corner Clearance at Signalized Intersections | February | Thanh Le, Frank Gross, Tim Harmon, and Kimberly Eccles | FHWA-HRT-17-084 |
| NCHRP Research Report 888: Development of Roundabout Crash Prediction Models and Methods | January | Erin Ferguson, James Bonneson, Lee Rodegerdts, Nick Foster, Bhagwant Persaud, Craig Lyon, and Danica Rhoades | |
| NCHRP Research Report 875: Guidance for Evaluating the Safety Impacts of Intersection Sight Distance | January | Kimberly Eccles, Scott Himes, Kara Peach, Frank Gross, Richard J. Porter, Timothy J. Gates, and Christopher M. Monsere | |
| NCHRP Research Report 892: Guidelines for Shielding Bridge Piers | January | Malcolm H. Ray, Christine E. Carrigan, and Chuck A. Plaxico | |
| NCHRP Research Report 881: Traffic Control Devices and Measures for Deterring Wrong-Way Movements | January | Melisa D. Finley, Raul E. Avelar, Steve P. Venglar, H. Gene Hawkins, Jr., and Haitham Al-Deek |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Safety Evaluation of Edge-Line Rumble Stripes on Rural Two-Lane Horizontal Curves | December | Scott Himes, Frank Gross, Bhagwant Persaud, and Kimberly Eccles | FHWA-HRT-17-069 |
| Safety Evaluation of Cable Median Barriers in Combination with Rumble Strips on the Inside Shoulder of Divided Roads | August | Raghavan Srinivasan, Bo Lan, Daniel Carter, Bhagwant Persaud, and Kimberly Eccles | FHWA-HRT-17-070 |
| NCHRP Web-Only Document 227: Design of Interchange Loop Ramps and Pavement/Shoulder Cross-Slope Breaks | January | Darren J. Torbic, Lindsay M. Lucas, Douglas W. Harwood, Marcus A. Brewer, Eun Sug Park, Raul Avelar, Michael P. Pratt, Akram Abu-Odeh, Elizabeth Depwe, and Kimberly Rau | |
| NCHRP Research Report 841: Development of Crash Modification Factors for Uncontrolled Pedestrian Crossing Treatments | January | Charles Zegeer, Raghavan Srinivasan, Bo Lan, Daniel Carter, Sarah Smith, Carl Sundstrom, Nathan J. Thirsk, Craig Lyon, Bhagwant Persaud, John Zegeer, Erin Ferguson, and Ron Van Houten |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Intersection Conflict Warning System Human Factors: Final Report | November | Vaughan W Inman and Steven Jackson | FHWA-HRT-16-061 |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Safety Evaluation of Wet-Reflective Pavement Markings | October | Craig Lyon, Bhagwant Persaud, and Kimberly Eccles | FHWA-HRT-15-065 |
| Crash Prediction Method for Freeway Facilities with High Occupancy Vehicle (HOV) and High Occupancy Toll (HOT) Lanes | July | ivaramakrishnan Srinivasan, Philip Haas, Priyanka Alluri, Albert Gan, and James Bonneson | |
| NCHRP Project 03-106: Traffic Control Device Guidelines for Curves | April | Paul J. Carlson, Bradford K. Brimley, Gene Hawkins, Scott Himes, Hugh McGee, and Frank Gross |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Speed and Safety in North Carolina | August | Libby Thomas, Raghavan Sirnivasan, Bo Lan, Wiliam Hunter, Carol Martell, and Eric Rodgman |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| NCHRP Research Report 705: Evaluation of Safety Strategies at Signalized Intersections | January | Raghavan Srinivasan, Jongdae Baek, Sarah Smith, Carl Sundstrom, Daniel Carter, Craig Lyon, Bhagwant Persaud, Frank Gross, Kim Eccles, Ajmal Hamidi, and Nancy Lefler |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Development of a Speeding-Related Crash Typology | April | Council, F.M., M. Reurings, R. Srinivasan, S. Masten, and D. Carter | FHWA-HRT-10-024 |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Safety Evaluation of Improved Curve Delineation | September | Raghavan Srinivasan, Jongdae Baek, Daniel Carter, Bhagwant Persaud, Craig Lyon, Kimberly Eccles, Frank Gross, and Nancy Lefler | FHWA-HRT-09-045 |
| Safety Evaluation of Lane and Shoulder Width Combinations on Rural, Two-Lane, Undivided Roads | June | Gross, F., P.P. Jovanis, K.A. Eccles, and K. Chen | FHWA-HRT-09-031 |
| NCHRP Project 5-19, "Analysis of Safety Effects for the Presence of Roadway Lighting" | June | Donnell, E.T., V. Shankar, and R.J. Porter | |
| NCHRP Report 5-19, "Analysis of Visual Performance Benefits from Roadway Lighting" | June | Bullough, J.D., M.S. Rea, and Y. Zhou | |
| NCHRP 5-19, "Review of the Safety Benefits and Other Effects of Roadway Lighting" | June | Rae, M.S., J.D. Bullough, C.R. Fay, J.A. Brons, J.V. Derlofske, and E.T. Donnell | |
| Low-Cost Safety Enhancements for Stop-Controlled and Signalized Intersections | May | FHWA | FHWA-SA-09-020 |
| NCHRP Report 633: Impact of Shoulder Width and Median Width on Safety | January | Stamatiadis, N., J. Pigman, J. Sacksteder, W. Ruff, and D. Lord | |
| NCHRP Report 641: Guidance for the Design and Application of Shoulder and Centerline Rumble Strips | January | Trobic, D.J., J.M. Hutton, C.D. Bokenkroger, K.M. Bauer, D.W. Harwood, D.K. Gilmore, J.M. Dunn, J.J. Ronchetto, E.T. Donnell, H.J. Sommer III, P. Garvey, B. Persaud, and C. Lyon | |
| NCHRP Project 15-27, "Safety Impacts of Design Element Trade-Offs" | January | Stamatiadis, N. |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Long Term Pavement Performance Computed Parameter: Frost Penetration | November | Selezneva, O.I., Y.J. Jiang, G. Larson, and T. Puzin | FHWA-HRT-08-057 |
| Wildlife-Vehicle Collision Reduction Study: Best Practices Manual | October | Huijser, M.P., P. McGowen, A.P. Clevenger, and R. Ament | |
| Safety Evaluation of Flashing Beacons at STOP-Controlled Intersections | March | Srinivasan, R., D.L. Carter, K.A. Eccles, B. Persaud, N.X. Lefler, C. Lyon, and R. Amjadi | FHWA-HRT-08-044 |
| Safety Evaluation of STOP AHEAD Pavement Markings | March | Gross, F.B., R. Jagannathan, B.N. Persaud, C. Lyon, K. Eccles, N. Lefler, and R. Amjadi | FHWA-HRT-08-043 |
| Cost Effective Safety Improvements for Two-Lane Rural Roads | March | Wang, Y., N.H. Nguyen, A.B.E. Levy, and Y. Wu | TNW2008-04 |
| NCHRP Project 17-29, "Methodology to Predict the Safety Performance of Rural Multilane Highways" | February | Lord, D. (Principal Investigator, Texas A&M Reserach Foundation) | |
| NCHRP Report 615: Evaluation of the Use and Effectiveness of Wildlife Crossings | January | Bissonette, J.A. and P.C. Cramer | |
| NCHRP Report 617: Accident Modification Factors for Traffic Engineering and ITS Improvements | January | Harkey, D.L., R. Srinivasan, J. Baek, F.M. Council, K. Eccles, N. Lefler, F. Gross, B. Persaud, C. Lyon, E. Hauer, and J.A. Bonneson | |
| NCHRP Report 627: Traffic Safety Evaluation of Nighttime and Daytime Work Zones | January | Ullman, G.L., M.D. Finley, J.E. Bryden, R. Srinivasan, and F.M. Council | |
| Framework for Selection and Evaluation of Bicycle and Pedestrian Safety Projects in Virginia | January | Natarajan, S., M.J. Demetsky, and K.E. Lantz Jr. | VTRC 08-R8 |
| Economic Impact of Traffic Incidents on North Carolina's Interstate Facilities | January | Khattak, A.J., C. Teague, X. Pan, Y. Fan, and D.A. Rodriguez | FHWA/NC/2006-53 |
| NCHRP Project 17-26, "Methodology to Predict the Safety Performance of Urban and Suburban Arterials | January | Harwood, D. (Principal Investigator, Midwest Research Institute) |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Safety Evaluation of Installing Center Two-Way Left-Turn Lanes on Two-Lane Roads | December | Persaud, B., C. Lyon, K.A. Eccles, N.X. Lefler, D.L. Carter, and R. Amjadi | FHWA-HRT-08-042 |
| NCHRP Project 25-27, "Evaluation of the Use and Effectiveness of Wildlife Crossings" | September | Bissonette, J.A. (Principal Investigator, Utah State University) | |
| Interchange Safety Analysis Tool (ISAT): User Manual | June | Torbic, D.J., D.W. Harwood, D.K. Gilmore, and K.R. Richard | FHWA-HRT-07-045 |
| FHWA Technical Report - Safety Analysis of Interchanges | June | Torbic, D.J., D.W. Harwood, D.K. Gilmore, and K.R. Richard | |
| Safety Effects of Left-Turn Phasing Schemes at High-Speed Intersections | January | Davis, G.A. and N. Aul | |
| Wildlife-Vehicle Collision Reduction Study: Report to Congress | January | Huijser, M.P., P.T. McGowen, J. Fuller, A. Hardy, and A. Kociolek |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| NCHRP Project 3-67, "Expert System for Recommending Speed Limits in Speed Zones" | November | Srinivasan, R., M. Parker, D. Harkey, D. Tharpe, and R. Sumner | |
| Safety Impacts of Pavement Edge Drop-offs | September | Hallmark, S.L., D. Veneziano, T. McDonald, J. Graham, R. Patel, and F.M. Council | |
| Pavement Marking Materials and Markers: Real-World Relationship Between Retroreflectivity and Safe | April | Bahar, G., M. Masliah, T. Erwin, E. Tan, and E. Hauer | NCHRP Project 17-28 |
| Comparative Evaluation of Automated Wind Warning Systems - Showcase Evaluation #15 | February | Kumar, M. and C. Strong |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Safety Evaluation of Red-Light Cameras | April | Council, F.M., B.N. Persaud, K.A. Eccles, C. Lyon, and M.S. Griffith | FHWA-HRT-05-048 |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Guidance for Future Design of Freeways with High-Occupancy Vehicle (HOV) Lanes Based on an Analysis | May | Cothron, A.S., S.E. Ranft, C.H. Walters, D.W. Fenno, and D. Lord | FHWA/TX-05/0-4434-P1 |
| Crash Analysis of Selected High-Occupancy Vehicle Fatalities in Texas: Methodology, Findings, and Recommendations | May | Cothron, A.S., S.E. Ranft, C.H. Walters, D.W. Fenno, and D. Lord | FHWA/TX-040-4434-1 |
| NCHRP Report 500: Guidance for Implementation of the AASHTO Strategic Highway Safety Plan, Volume 8 | January | Lacy, K., R. Srinivasan, C.V. Zegeer, R. Pfefer, and T.R. Neuman | |
| NCHRP Report 518: Safety Evaluation of Permanent Raised Pavement Markers | January | Bahar, G., C. Mollett, B. Persaud, C. Lyon, A. Smiley, T. Smahel, and H. McGee | |
| NCHRP Report 524: Safety of U-Turns at Unsignalized Median Openings | January | Potts, I.B., D.W. Harwood, D.J. Torbic, K.R. Richard, J.S. Gluck, H.S. Levinson, P.M. Garvey, and R.S. Ghebrial |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Impact Induced Fires & Fuel Leakage: Statistical Analysis of FARS and State Date Files (1978-2001) | October | Friedman, K., T. Kenney, and E. Holloway | |
| Spatially Disaggregate Panel Models of Crash and Injury Counts: The Effect of Speed Limits and Design | January | Kweon, Y.J. and K.M. Kockelman |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Safety Effectiveness of Intersection Left and Right Turn Lanes | July | D.W. Harwood, K. M. Bauer, I.B. Potts, D. .J. Torbic, K. R. Richard, E.R. Kohlman Rabbani, E. Hauer, and L. Elefteriadou | FHWA-RD-02-089 |
| NCHRP Project 8-36, Task 26, "Surface Transportation Safety and Investment" | July | Neuman, T. (CH2M HILL) |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Overview of Current Intersection Safety Conditions: Phase I Result | November | D.W. Harwood, D.J. Torbic, K.R. Richard, and Y.R. Mohamedshah | |
| Implementation of GIS-Based Highway Safety Analyses | January | Richard C. Smith, David L. Harkey, and Bobby Harris | FHWA-RD-01-039 |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Prediction of the Expected Safety Performance of Rural Two-Lane Highways | December | D. W. Harwood, F. M. Council, E. Hauer, W. E. Hughes, and A. Vogt | FHWA-RD-99-207 |
| Type | Pub Date | Author | Report Number |
|---|---|---|---|
| Accident Models for Two-Lane Rural Segments and Intersections | October | Andrew Vogt and Joe Bared | FHWA-RD-98-133 |
| Safety Effects of Cross-section Design on Rural Multi-lane Highway | May | Jun Wang, Warren E. Hughes, Richard Stewart | FHWA-RD-98-071 |
| Type | Pub Date | Author | Report Number |
|---|---|---|---|
| An Investigation of Older Driver Freeway Needs and Capabilities | May | R. Knoblauch, M. Nitzburg, and R. Seifert | FHWA-RD-95-194 |
| Capacity and Operational Effects of Mid-Block left Turn Lanes | January | James A. Bonneson and Patrick T. McCoy | NCHRP-295 |
| Small Target Visibility | January | Doug Mace |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Development of Severity Indices for Roadside Objects: Resource Materials | September | Forrest M. Council and J. Richard Stewart | FHWA-RD-95-165 |
| Traffic Operations Control for Older Drivers. Final Report | March | R. Knoblauch, M. Nitzburg, D. Reinfurt, F. Council, C. Zegeer, and C. Popkin | FHWA-RD-94-119 |
| Median Intersection Design | January | Douglas W. Harwood | NCHRP-375 |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Accident Relationships of Roadway Widths on Low-Volume Roads | January | Charles V. Zegeer | NCHRP-362 |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Development of Relationship Between Truck Accidents and Geometric Design: Phase 1. Final Report | August | S.-P. Miaou, P.S. Hu, T. Wright, S.C. Davis, and A.K. Rathi |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Study Designs for Passing Sight Distance Requirements: Final Report | April | Warren Hughes, Sarath Joshua, and Hugh McGee | FHWA-RD-91-078 |
| Title | Pub Date | Author | Report Number |
|---|---|---|---|
| Zero Tolerance: Four States Experience | Unknown |
John Lacey and Ralph Jones |
DOT-HS-809-053 |
| Study of Accidents at Signalized Intersections Phase I Final Report | Unknown | ereen J. Wolverton and John J. Monce | N/A |
| Safety Effectiveness of Intersection Left-and Right-Turn Lanes | Unknown | Douglas W. Harwood, Karin M. Bauer, Ingrid B. Potts, Darren J. Torbic, Karen R. Richard, Emilia R. Kohlman Rabbani, Ezra Hauer, Lily Elefteriadou, and Michael S. Griffith | N/A |
| NCHRP-420: Impacts of Access Management Techniques | Unknown | Jerome Gluck, Herbert S.Levinson, and Vergil Stover | N/A |
| Stopping Sight Distance - II | Unknown | Kay Fitzpatrick | N/A |
| An Attempt to Define the Relationship between Forces to Crash Test Vehicles and Occupant Injury | Unknown | Forrest Council et al. | FHWA-RD-95-165 |
Last updated: Tuesday, July 18, 2023