Safety Impacts of Different Speed Limits on Cars and Trucks


Book Description

The objectives of this study were to determine whether differential or uniform speed limits are more beneficial to transportation safety and traffic operations on Interstate highways. The approach to achieving this objective was to examine speed and accident data from States employing both types of limits. Speed data were collected in 12 States at rural and urban locations representing all speed limits currently established on the Interstate highway system for cars/trucks, i.e., 55/55 mi/h (89/89 km/h), 65/55 mi/h (105/89 km/h), 65/60 mi/h (105/97 km/h), and 65/65 mi/h (105/105 km/h). Accident data were obtained from nine States which were geographically distributed across the country and representative of all rural Interstate speed limits currently established. For the speed data collected, a number of measures of effectiveness (MOEs) were examined including mean speed, speed variance, compliance, and speed distribution measures. For the accident data collected, types of crashes were examined (e.g., rear-end) along with vehicle type involvement (e.g., car-into-truck) and crash severity. This final report summarizes the effects of uniform and differential speed limits on transportation safety and traffic operations as determined by the examination of speed and accident data.







Managing Speed


Book Description

TRB Special Report 254 - Managing Speed: Review of Current Practices for Setting and Enforcing Speed Limits reviews practices for setting and enforcing speed limits on all types of roads and provides guidance to state and local governments on appropriate methods of setting speed limits and related enforcement strategies. Following an executive summary, the report is presented in six chapters and five appendices.










Effects of the 55 Mph Speed Limit


Book Description










Safety Impacts and Other Implications of Raised Speed Limits on High-speed Roads


Book Description

TRB's National Cooperative Highway Research Program (NCHRP) Research Results Digest 303: Safety Impacts and Other Implications of Raised Speed Limits on High-Speed Roads explores the effects of raised speed limits from 55 miles per hour or greater on freeways and non-freeways in rural and urban settings. The effects considered included impacts on safety and operations, as well as socioeconomic and environmental effects. The full report is available on the TRB website as NCHRP Web-Only Document 90.




Strong Towns


Book Description

A new way forward for sustainable quality of life in cities of all sizes Strong Towns: A Bottom-Up Revolution to Build American Prosperity is a book of forward-thinking ideas that breaks with modern wisdom to present a new vision of urban development in the United States. Presenting the foundational ideas of the Strong Towns movement he co-founded, Charles Marohn explains why cities of all sizes continue to struggle to meet their basic needs, and reveals the new paradigm that can solve this longstanding problem. Inside, you’ll learn why inducing growth and development has been the conventional response to urban financial struggles—and why it just doesn’t work. New development and high-risk investing don’t generate enough wealth to support itself, and cities continue to struggle. Read this book to find out how cities large and small can focus on bottom-up investments to minimize risk and maximize their ability to strengthen the community financially and improve citizens’ quality of life. Develop in-depth knowledge of the underlying logic behind the “traditional” search for never-ending urban growth Learn practical solutions for ameliorating financial struggles through low-risk investment and a grassroots focus Gain insights and tools that can stop the vicious cycle of budget shortfalls and unexpected downturns Become a part of the Strong Towns revolution by shifting the focus away from top-down growth toward rebuilding American prosperity Strong Towns acknowledges that there is a problem with the American approach to growth and shows community leaders a new way forward. The Strong Towns response is a revolution in how we assemble the places we live.