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Developing Enhanced Curve Advisory Speed and Curve Safety Assessment Guidelines

Michael Paul PrattSrinivas Reddy GeedipallyRaul AvelarMinh Le (Engineer)Dominique Lord

出版	Texas A & M Transportation Institute, 2019
URL	http://books.google.com.hk/books?id=ZAMOyAEACAAJ&hl=&source=gbs_api

註釋The Texas Department of Transportation (TxDOT) is in the process of conducting several parallel efforts to evaluate rural highway horizontal curves. Following the adoption of the 2011 Texas Manual on Uniform Traffic Control Devices, district personnel are checking and updating posted curve advisory speeds and other curve traffic control devices (e.g., Chevrons) in response to the December 31, 2019, compliance date. Recent legislation has allowed regulatory speed limits to be increased to 75 mph on some rural highways, resulting in a need to check and evaluate curves that had not previously been signed with advisory speeds. There is also renewed interest in implementing pavement friction treatments through the Highway Safety Improvement Program. In this research project, researchers collected and analyzed data to extend TxDOT's curve advisory speed setting procedures to rural multilane highways and freeways as well as two-lane rural highways with speed limits of 75 mph. Researchers also improved TxDOT's global positioning system (GPS) -based curve measurement system's capabilities to measure grade. Finally, the researchers drafted the Horizontal Curve Evaluation Handbook to aid TxDOT's practitioners in using the GPS-based system for evaluating curves.