Energy and Transportation | Research and Development
Geometric Design
Our Transportation Research Center conducts research to determine the best design practices for moving people and goods across our highway system as efficiently and safely as possible.
Our research looks at how different design elements impact roadway safety and operations. MRIGlobal is nationally recognized for highway geometric design research expertise. Our projects address lane width, intersection design, interchange ramp design, and pedestrian and bike facilities. We develop geometric design guidance for highway agencies based on safety and traffic operational analyses. When innovative or untested approaches to highway design are implemented, MRIGlobal evaluates how the design affects safety, travel speed, lane departures, yielding rates, or capacity.
Capabilities
MRIGlobal’s geometric design capabilities include:
MRIGlobal has extensive experience in evaluating the relationship between the geometric design of intersections and intersection safety/operations.
MRIGlobal has been at the forefront of much of the design and safety research related to intersections, including the development of intersection crash predictive models for the Highway Safety Manual, improved intersection sight distance models for the AASHTO Green Book, and design guidance to accommodate motor vehicles, pedestrians, bicyclists, and trucks at intersections.
MRIGlobal is well known for developing design guidance for mainline ramp terminals and software programs to analyze ramp and interchange safety. We use Empirical Bayes methodologies to develop safety performance functions for ramp configurations and statistical relationships between crashes and interchange design elements.
Having developed design guidance for mainline ramp terminals, interchange spacing, and ramp design speed, MRIGlobal has years of expertise in research concerning interchanges and freeway ramps. Our staff has developed software programs to analyze ramp and interchange safety, statistical models to define the relationship between crashes and interchange ramps and speed-change lanes, and geometric design guidelines for freeway interchanges with operational or safety issues.
MRIGlobal developed the current Highway Safety Manual methodology to predict the safety performance of roadway segments and intersections on urban and suburban arterials, and we have developed geometric design guidance on lane widths, turn lanes, medians, and U-turns, as well as the accommodation of motor vehicles, pedestrians, bicyclists, and trucks on urban and suburban arterials.
MRIGlobal is nationally recognized for its research on rural highway design, including development of design guidance on passing lanes and climbing lanes, median cross section, roadside clear zones, and shoulder and centerline rumble strips. We recently developed design guidelines for very low-volume local roads, recently published as the AASHTO Geometric Design Guidelines for Very Low-Volume Local Roads.
MRIGlobal is nationally recognized for its development of guidance on designing roadways to better accommodate pedestrians and bicyclists, including development of recommendations for:
- Cconventional intersections
- Midblock crossings
- Parking lane, bicycle lane, and travel lane widths for urban and suburban arterials
MRIGlobal has contributed to the editing and final production of the first edition (2004) of the AASHTO Guide for the Planning, Design, and Operation of Pedestrian Facilities (the Pedestrian Guide) and the fourth edition (2012) of the AASHTO Guide for the Development of Bicycle Facilities (the Bicycle Guide), and continues to be involved in their recent updates.
Geometric Design Research Topics
MRIGlobal has an array of experience. We conduct analyses of geometric design features including:
• Lane width
• Shoulder width
• Pavement width allocation (including bike lanes)
• Passing lanes
• Intersection design
• Interchange design
• Access design and density
• Roundabouts
• 13 controlling criteria for geometric design
OUR STAFF
Our Transportation Research Center staff have decades of experience and national recognition in highway geometric design, traffic safety, and traffic operations research.
For more than 45 years, MRIGlobal’s experts have researched the impact of geometric design features on safety and operations. Our staff have long been involved in the Transportation Research Board’s Committee on Highway Geometric Design, and regularly present research at national and international conferences. Our research results are published in national policies and guidance documents that are implemented at state and local levels.
Work with us
MRIGlobal looks forward to contributing our expertise where it matters most.
Want to work with an industry leader in highway safety and technology? If you’d like to learn more about what MRIGlobal can do for your business or project, try our custom Project Quote Tool.