Selection of Pedestrian Crossing Treatments at Controlled and Uncontrolled Locations.

摘要

Designers and traffic engineers have to make decisions on selecting a pedestrian treatment whenever designing a new pedestrian facility or retrofitting an existing one. The goal is either to provide or improve pedestrian safety at pedestrian crossing facilities, including controlled locations of signalized intersections and approaches with stop and yield signs, and uncontrolled locations of intersections and midblock sites. Currently, the Indiana Department of Transportation (INDOT) has limited resources on pedestrian treatment selection that does not take into consideration key elements such as number of lanes and the existence of a raised median. Therefore, there is a need to find a more detailed and comprehensive approach to providing guidelines when deciding on a pedestrian crossing treatment. The approach has to be practical and can be easily utilized by traffic and design engineers, planners, and other constituents. Most of the State DOTs developed their guidelines on pedestrian crossing treatment based on several resources. However, the 2002 FHWA?RD?01?075 study titled “Safety Effects of Marked Vs. Unmarked Crosswalks at Uncontrolled Locations” was adopted by several states either “as is,” with some modifications, or referenced as a source on pedestrian crosswalk selection. State DOTs mainly use standards and guidelines from the National MUTCD, Part 3 and NCHRP Report 672 for roundabout crosswalk markings. In general, there are no clear warrants for grade separation treatment. In addition, there is a need for a national and comprehensive study to develop practical guidelines on pedestrian crossing treatments, especially on multilane roadways, complex intersections, and when the speed is 45 mph or more. This study proposed guidelines on crosswalk markings and treatment selection of pedestrian crossings based on a synthesis of federal and state reports, guidelines, design manuals, polices, and other relevant publications. It is recommended to adopt these guidelines as a reference for pedestrian treatment selection at INDOT. The results of a survey on pedestrian crossing treatments indicate that the most effective and most frequently used treatments by the different states represented in the survey are advanced signs, crosswalk signs and pavement markings, countdown displays at signalized intersections, curb extensions, high?visibility signs and markings, and median refuge islands. The least effective and least frequently used treatments are automated detection, in?roadway warning lights, overhead flashing beacons (passive), pedestrian crossing flags, pedestrian railings, and split midblock signals. In addition, the main recommendation on high?speed divided highway pedestrian crossings is to provide enough time for pedestrian to cross the entire width of the intersection without a median whenever there is a demand.