TxDOT Research Library - TxDOT Research Project

Show:

Guidelines for Design and Operation of U-turns

Project Summary

U-turn lanes are commonly provided at diamond interchanges to reduce delay for U-turning traffic and for the interchange as a whole; however, there are currently many unknowns related to their design, operation, and use. This project provides TxDOT with implementable guidelines for designing and operating U-turn lanes at diamond interchanges. The research team will identify and investigate demand and capacity factors affecting U-turn lane use, determine the capacity of U-turn lanes under various geometric and operational conditions, and determine the anticipated effectiveness of proposed solutions to U-turn operational issues. The research team will structure these guidelines for inclusion in the Roadway Design Manual and other manuals dealing with access management, design, and operations of facilities. This project will also provide a cross-sectional safety analysis of existing U-turn configurations. The research team will provide a self-calculating spreadsheet tool as a key product of the safety analysis that can be used to predict U-turn safety performance under a variety of conditions.

Project Number

0-6894

Status

Completed

link icon Copy link to this project.