Gap Acceptance and Traffic Interaction in the Freeway Merging Process. Volume I. A Nationwide Study of Freeway Merging Operations

摘要

Volume 1 of the final report, which consists of seven volumes and a summary report, introduces the research contract entitled 'Gap Acceptance and Traffic Interaction in the Freeway Merging Process.' Field studies for the collection of data were carried out at thirty-two entrance ramps located in eight of the major metropolitan areas in six states. Data were collected using aerial photography. The films were analyzed using time oriented techniques. The report discusses in detail the aerial photographic technique used, the data reduction methods and the study sites selected. Data editing routines for removing errors made during the film analysis and punching of the data cards are discussed. The analysis of the data for basic traffic parameters are discussed and some of these parameters such as speed, volume, and density are used to illustrate the merging operation at each study site. The qualitative effect of various geometric elements such as acceleration lane length and shape, angle of convergence and grades on merging as mirrored by the traffic parameters of volume, density, speed, and acceleration noise are discussed. No conclusions are presented in this report; however, the report serves to demonstrate not only the nature of the data available, but also the vast quantity of the data involved. (Author)