Triple Left-Turns: An Analysis of Capacity and Other Issues

摘要

A study of the characteristics of triple left turns was performed. Five tripleleft turn sites in Orange County, California were identified. Manual saturation flow rate studies at each site were performed using electronic counter boards. Queue discharge times were collected for all vehicles by land and by cycle. Across all five sites, a sample consisting of 4742 lane-cycles and 34898 vehicles was compiled for analysis. On average, these triple left turns supported flows of 795 vehicles per hour (vph), received a 19 percent split of the total cycle time, and spend 57 percent of that split time servicing the queue.