Visual Vulnerability of Streetscapes to Elevated Structures

Abstract

Overhead expressways have damaged streetscapes in some countries, and new transportation system structures will possibly repeat the same failure. To prevent this, transportation planners must know which streetscapes are vulnerable to elevated structures and which are resistant to them. Hence, the relationship between streetscape type and visual vulnerability to an overhead guideway and an elevated station of new transportation systems was studied experimentally. Images of elevated structures were superimposed upon selected photographs of urban and suburban street scenes and presented to respondents. Using respondents' rating scores, the separate effects of guideway, station, and background scene were analyzed. We found that the major determinant of visual vulnerability is not visual quality of streetscapes but visual type; therefore, it is possible to judge visual vulnerability of streetscapes from visual type.