Development of guidelines for operationally effective raised medians and the use of alternative movements on urban roadways.

PDFTech ReportFHWA/TX-13/0-6644-1Project 0-6644Access control (Transportation)MediansMedian openingsLeft turn lanesU turnsIntersectionsDesignUrban highwaysSimulationState of the practiceGuidelinesTexasTexas. Dept. of Transportation. Research and Technology Implementation OfficeQi, YiChen, XiaomingYu, LeiLiu, HaixiaLiu, GuanqiLi, DaPersad, Khali R.Pruner,KristopherTexas Southern University. Dept. of Transportation StudiesUnited States. Federal Highway AdministrationNTL-HIGHWAY/ROAD TRANSPORTATION-DesignNTL-PLANNING AND POLICY-Access ManagementUS Transportation CollectionThe development of raised medians is an important access management technique commonly used in urban settings. Itcan be used to control or restrict mid-block left turns, U-turns or crossing maneuvers for implementing of alternativeleft-turn/U-turn movements. The objective of this research project was to develop guidelines for operationally effectiveraised medians and the use of alternative movements on urban roadways. To fulfill this goal, the researchers (1)reviewed and synthesized national and peer states\ue2\u20ac\u2122 practices, (2) conducted survey of traffic engineers, (3) conductedfield studies, (4) analyzed the design issues relating to raised medians and alternative movements through simulationstudies, and (5) developed guidelines for future implementation of raised medians and representative alternativemovements in Texas.The results of this study provide recommendations on some critical design issues in the use of raised medians,including median widths, median left-turn lane lengths, placement of median openings, and the use of directionalmedian openings. In addition, a set of implementation-oriented guidelines regarding the applicability, geometricdesign, and access management of three typical types of alternative movements, including restricted crossing U-turn(RCUT), median U-turn (MUT) and continuous flow intersection (CFI), were developed