Author : Hansel Hon Chung Wang
Publisher : Unknown
Page : 0 pages
File Size : 44,6 Mb
Release : 1979
Category : Lane lines (Roads)
ISBN : OCLC:1433241769
Evaluation of Pavement Marking at Merging and Diverging Areas by Hansel Hon Chung Wang Pdf
The purpose of this thesis is to evaluate the pavement marking at merging and diverging areas from the views of safety and capacity. Two non-accident methods of evaluation were utilized - the Critical Incident Survey and the Vehicle Trajectory Survey, with the application of the before-and-after principle. The Critical Incident Survey involved a manual traffic counting technique. It began with the identification of the types of critical incident at each test location- The number of critical incidents by type were recorded for each test marking pattern during its peak periods. Assuming that the effectiveness of each test marking pattern decreases with increasing number of critical incidents experienced at the test locations and vice versa, the number of critical incidents and the number of critical incidents per unit volume were used as parameters for evaluation of the test marking patterns. The former was tested statistically for significance while the latter was presented visually in the form of a profile- The Vehicle Trajectory Survey involved a filming technique. The behaviour of traffic passing through the critical areas of merging and diverging were recorded by a 16 mm movie camera. By tracing the travel paths of vehicles, vehicle dynamics were readily derived. Assuming that lateral displacement and longitudinal velocity were able to reflect some differences in drivers' response to the test marking patterns and thus their effectiveness, in terms of safety and capacity, they were selected as measures- The variances of the parameters and the means of the longitudinal velocity were used as measures of comparison- conclusions were arrived at independently through these two surveys. The principal findings include : 1. For the continuity lines at merging and diverging areas, a wider marking pattern (20/30 cm) is more effective than that of the current Canadian Standard. 2- Patterns with the merging and diverging areas closed by the continuity lines are more effective than those with these critical areas opened.
