What We Do
Transportation Safety
We specialize in advancing transportation safety through comprehensive research, analysis, and development of safety performance functions (SPFs) and crash modification factors (CMFs). We focus on mitigating risks for vulnerable road users, including pedestrians, bicyclists, motorcyclists and road workers, and improving roadway safety in work zones. Our expertise extends to investigating roadway departure events, optimizing safety countermeasures, and evaluating the effectiveness of various safety countermeasures to reduce crashes and fatalities.
Traffic Control Devices
We have a well-established reputation for data-driven research that investigates the design, application, and maintenance of traffic control devices. We specialize in designing and testing solutions for signs, pavement markings, traffic signals, and other types of traffic control devices, and we evaluate their effectiveness in both permanent and temporary traffic control settings. Our research is used to develop implementable guidelines and policies for transportation agencies to use in improving safety and operations in a wide variety of roadway environments.
Road and Intersection Design
We excel in developing practical solutions for roadway design that promote safety and efficiency. We specialize in designs for rural highways, urban and suburban streets, pedestrian and bicycle facilities, and intersections, including roundabouts and innovative intersection designs. Additionally, we investigate influences on speed and its effects on operations and safety, producing guidance for setting speed limits and designing roadways that correspond with those speeds. Using these areas of expertise, our research addresses safety concerns and contributes to designing roadways that benefit all road users.
Active Transportation
We support the growth and safety of non-motorized transportation options, including pedestrian and bicycle infrastructure. We focus on the design of bikeways, shared-use paths and pedestrian facilities that prioritize safety and comfort of vulnerable users. Our expertise in exposure-based safety models helps in optimizing active transportation infrastructure design based on real-world needs, while our non-motorized data analysis enhances the understanding of usage patterns and risks. By developing innovative safety strategies and evaluation tools, we strive to create safer, more sustainable urban and rural transportation systems for pedestrians and cyclists.
Data-Driven Solutions
We harness the power of data-driven methodologies to predict and mitigate transportation-related risks. Through the integration of machine learning algorithms, predictive modeling, and exposure-based models, we enhance traffic safety decision-making and develop proactive safety interventions. By utilizing crowdsourced data, vehicle probe data and connected vehicle technology, we offer state-of-the-art predictive tools that improve the understanding of traffic flow, safety patterns, and potential risk factors. Our solutions enable transportation agencies to make informed decisions that enhance public safety and optimize infrastructure.
Our Focus Areas
Pavement Markings
Examining the composition, installation and performance of pavement markings.
Visibility
Assessing the visibility of traffic control devices, road users and workers.
Work Zones
Improving safety and efficiency in work zones for all road users and workers.
Wrong-Way Driving
Investigating the problem, evaluating countermeasures, testing detection technologies and developing new solutions.
Speed
Identifying the factors that influence speed and how speed affects the roadway environment.
Innovative Intersections
Developing and improving resources to design and implement roundabouts and other innovative intersection designs.
Roadway Cross-Sections
Providing practical design solutions (such as passing lanes, turning lanes and pedestrian/bicycle facilities) that promote safety and efficiency for motorists and for non-motorized road users.
Standards and Guidelines
Producing data-driven, implementable research results that support Texas and national policy and guidance.
Emerging Data Sources
Using new and emerging data sources to take a new approach at solving issues that have been challenging the profession for many years.
Technology
Investigating how new technologies — such as connected automated vehicles, advanced driver assistance systems, and smart work zones systems — impact safety and operations.
Our Work
Visibility Website
TTI has established a comprehensive research program related to the visibility of traffic signs and pavement markings. Our researchers have conducted numerous studies to evaluate how well drivers can see signs and markings, both during the day and at night, and how transportation agencies can improve signs and markings to meet the needs of drivers and driving automation systems. TTI research in this area cuts across other important areas of transportation research — older driver issues, work zone safety and CAV considerations — all are part of the picture when it comes to “seeing the road.”
TxDOT Traffic Control Device Analysis, Testing and Evaluation Program
Since 2003, TTI has led the TxDOT Traffic Control Device Analysis, Testing and Evaluation Program, which provides a mechanism to quickly and effectively conduct high priority evaluations of issues related to traffic control devices. The program evaluates new devices or technologies, new applications of an existing device or technology, material performance and changes in practices. Examples of various evaluations include human factors, machine vision performance, safety and operational effects, visibility assessments and cost effectiveness analyses. The activities conducted support the development of policy, specifications, guidelines, manuals and training.
Safety Evaluation of On-Street Bicycle Facility Design Features
TTI led a research team that prepared NCHRP Research Report 1136: On-Street Bicycle Facility Design Features: A Guide for the Transportation Research Board’s National Cooperative Highway Research Program. This report presents a state-of-the-art, data-driven guide for selecting context-appropriate design features for safety improvements of separated and non-separated on-street bicycle lanes. The report provides state DOTs with detailed information on the anticipated safety benefits of bicycle network design features across various contexts, the relationship between these features, and the risk of midblock (non-intersection) bicycle crashes.
Posted Speed Limit Setting Procedures and Tool: User Guide
Several factors are considered within engineering studies when determining the posted speed limit, including the 85th percentile speed, which is based on the driving behavior of most drivers (85 percent). TTI led a research team that provided and explained a speed limit setting procedure (SLS-Procedure) that considers factors beyond the 85th percentile speed, including the safety associated with the roadway design. This report also provides instructions for using an automated version of the SLS-Procedure via a spreadsheet-based Speed Limit Setting Tool.
Horizontal Curve Evaluation Handbook and Horizontal Curve Tool
As part of TxDOT Project 0-6960: Enhancing Curve Advisory Speed and Curve Safety Assessment Practices, TTI developed the Horizontal Curve Evaluation Handbook. This handbook provides engineers and technicians with a consolidated source for applying all the preceding analysis tools to assess curve safety and implement needed treatments. TTI also developed the Texas Curve Evaluation Suite (TCES) spreadsheet tool, which facilitates the analysis of horizontal curve data to identify needed traffic control devices and pavement friction improvements.
STEM Retroreflectivity Curriculum
Through the SAFE-D University Transportation Center, TTI led a project that produced a hands-on classroom curriculum with support materials to help students use discovery techniques to explore the science of retroreflectivity and its applications to transportation. This curriculum focuses on how traffic signs and pavement markings use reflection and refraction to direct light from a vehicle’s headlights back to the driver, allowing drivers to see these traffic control devices at night. These materials can be used by teachers and other professionals to connect real-world applications in transportation to academic concepts to enhance the STEM learning experience for students.
National Work Zone Information Clearinghouse
The National Work Zone Safety Information Clearinghouse is web-based resource dedicated to providing the transportation construction industry and the public with comprehensive information to improve motorist, worker and pedestrian safety in roadway work zones. The Clearinghouse is a project of the American Road & Transportation Builders Association Transportation Development Foundation and is operated in cooperation with the U.S. Federal Highway Administration and TTI.
