Click for next page ( 24


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 23
23 Figure 21. Alternative D3--coping with protruding surface in contrasting color. are placed in only some or a few of the concrete barrier sec- VIEWER PREFERENCE SURVEY tions through the length of the entire installation. Fewer aes- thetic sections permit costs to be lower. An example of this The viewer preference survey was performed in preparation approach is to use key aesthetic elements to highlight the for establishing the design guidelines for aesthetic concrete beginning and end of a bridge only and use a standard barrier barriers and see-through bridge rails. The barriers selected for shape between the aesthetic elements. the study met fundamental aesthetic principles of attractive An underlying premise about this approach is that barriers form, line, balance, and proportion and were studied in differ- do not have to be a repeatable cross section. This opens other ent background settings (i.e., rural and urban). options for creating balance, uniqueness, and innovation into It was noted in the study that most people respond favorably the design. This application may be most appropriate for to a rail aesthetic if it is different than what they are used to shorter spans where the driver sees the entire length at once, seeing. Of course, this does not provide suitable guidance to such as spans found in urban areas. designers in how to design an aesthetically pleasing rail. The Figure 22. Alternative D4--coping with lengthened protruding surface.

OCR for page 23
24 Figure 23. Alternative D5--coping with lengthened protruding surface in contrasting color. experience gained by the researchers indicates that most aes- To what degree does barrier design determine how a thetic rail designs will meet with the favor of the general pub- viewer feels about a scene? lic. If it can be assumed that people will like a particular Is barrier design likely to change the way a viewer feels design, the questions, then, are "will people even notice the about a scene? rail?" and "is there a preference for a particular rail or barrier Is there a preference for a particular barrier design? design?" The researchers performed a viewer preference sur- vey using a controlled photographic evaluation process to aid Barrier rails are perceived in a distance/time/setting frame- in answering these questions. The goals of the survey were to work. Modeling all these conditions to achieve a real-time test assess the following: condition is economically prohibitive. The researchers believed that sufficient insight into viewer preferences could be gained Will people notice changes to a scene due to barrier through a static image survey. The survey attempts to identify design? the gross characteristics of rail design that are noticed and/or Figure 24. Alternative E--open metal rail.

OCR for page 23
25 Figure 25. Alternative F--open tube rail. preferred. The gross characteristics incorporated are the pre- sion (2 to 3 seconds per scene) and then asked to rank viously discussed design techniques that modify rhythm and the scenes in terms of their visual quality, from mem- sequence impressions. The viewer preference photographic ory. A descriptor term was provided to aid the respon- survey was structured as follows: dent in describing the feeling or emotion sensed when the photograph of the barrier/rail and scene were Five barrier/rail designs, shown in Figure 27, were used. viewed together. Sets of three different descriptors Three of these were concrete, and two were steel see- were used depending on the scene. The descriptor sets through bridge rails. A plain, single-slope concrete bar- were: rier and W-beam guardrail were used as a control. Com- Photograph Set 1--Rural 1 (Figure 28) puter models of the rails were created and then inserted Architectural feeling into photographs of rural and urban background scenes. Rural feeling This resulted in 30 scenes. Interesting feeling Two hundred and fifty randomly selected individuals Photograph Set 2--Urban bridge (Figure 29) were shown a series of three scenes in rapid succes- Upscale feeling Figure 26. Alternative G--concrete post and beam.

OCR for page 23
26 Figure 27. Barrier/rail designs used in viewer preference survey. Figure 28. Photo Set 1--rural 1.

OCR for page 23
27 Figure 29. Photo Set 2--urban bridge. Busy feeling Results of the Viewer Preference Survey Historic feeling Photograph Sets 3 and 6--Rural and urban control The researchers found a preference among the respondents sets, respectively (Figure 30) for the alternative designs over the common rail or barrier in Scenic feeling all settings, but perhaps less so in complex urban backgrounds. High-speed feeling Additionally, the researchers found smaller differences in pref- Boring feeling erences between the new alternatives themselves. It is hypo- Congested feeling thesized that much of the difference is due to the character of Typical feeling background influence. Regardless of the barrier or rail used, the Stressful feeling urban setting consistently elicited a busy or cluttered response. Photograph Set 4--Urban at grade (Figure 31) In urban environments, with enormous amounts of background Historic feeling clutter, the barrier or rail had very little effect on the respon- Common feeling dents, which suggests that providing an aesthetic application to Cluttered feeling the barrier is unwarranted. Responses were more positive to Photograph Set 5--Rural 2 (Figure 32) changing the aesthetics of the barrier in the rural settings, Country feeling where the barriers were more prominent in the scene and did City feeling not compete for the viewer's attention with other background Anywhere feeling images. With the exception of the W-beam guardrail, all the barrier designs had nearly the same effect on the rating of the The three scenes each contained different barrier/rail designs scene. The aesthetic preference produced two components: in different settings. The process of presenting photographic the quality of the beauty and the quality of the experience. scenes to the respondent was repeated five times. Each time a A significant bias regarding a particular alternative design different design and setting combination was presented to the may reflect a subjective bias on the part of the viewer or may respondent. Each design was tracked for its ranking in differ- be simply due to the barrier's visual prominence (i.e., contrast) ent settings and against different rail choices. Additionally, the in a given setting. Designing for individual subjectivity will participants were asked to rank the barriers and rails as to "best" most probably be inconsistent in most cases. Of more value to and "worst" designs. the engineer or designer will be the question of how much

OCR for page 23
28 Figure 30. Photo Sets 3 and 6--rural and urban control images. Figure 31. Photo Set 4--urban at grade.