Acoustic Vitality Evaluation in Urban Public Spaces (Case Study: Darvazeh Isfahan, Shiraz, Iran)

Document Type : Original Research

Authors
P. Najafi
S. Lotfi
A. Soltani
M. Sholeh
Urban Planning & Design Department, School of Art & Architecture, Shiraz University, Shiraz, Iran
Abstract
Aims: The present study aims to measure the perceptual quality of sound in the case study of “Darvazeh Isfahan” of Shiraz (a public urban space) in two objective and subjective dimensions.

Participants & Methods: The study method in objective analysis is using acoustic simulation software and measurement of five acoustic components and characteristics of sound including sound pressure level (SPL), sound clarity (C), and sound transmission index (STI). Mental dimension analysis was conducted through direct interviews with people in the space during the day, at three intervals in the morning, noon and afternoon. In the interview process, interviewees were asked to respond to the three components of voice information, voice perception, and auditory rating. Simultaneously, the audio content of the study area was recorded using a calibrated voice recorder.

Findings: The results of the analysis in objective dimension indicate the lack of space acoustic transparency in the contextual and background noise measurement components. Although the audio quality of the sound is normal at all three intervals, in some cases the sound intensity level is poor. The direct sound transmission index is in normal condition. On the subjective side, different audio content was heard over three intervals. In the morning, interviewees identified the buzzing, motorcycling, walking and talking. At noon, in addition to the audio content mentioned, the sound of music was also heard. In the afternoon, motorcycles, cars, and people’s conversations were the main audio content of the space.

Conclusion: Through overlaying the objective and subjective analysis, it has identified the subareas of the study space that have difficulty in perceiving the quality of sound. In summary, location-based urban design solutions for improving perceptual sound quality under problem areas are presented. Despite the fact that the present study might be restricted to a urban space in Shiraz, the findings could impart fruitful information for implicating appropriate acoustic vitality guidelines in urban public spaces.

Keywords

Subjects

[1] Regional Office for Europe. Data and statistics [Internet]. World Health Organization. 2019 [cited 2019 Aug 27]. Available from: http://www.euro.who.int/en/health-topics/environment-and-health/noise/data-and-statistics
[2] Faizi M, Monam A, Ghazizadeh N. Evaluation Users Acoustic Comfort in Urban Parks Case study: Tehran Urban Parks. Journal of Environmental Science and Technology. 2015;16(1):503–14.
[3] Carles JL, Barrio IL, de Lucio JV. Sound influence on landscape values. Landscape and Urban Planning. 1999 Jan 25;43(4):191–200.
[4] Yamada Y. Soundscape-based forest planning for recreational and therapeutic activities. Urban Forestry & Urban Greening. 2006 Oct 2;5(3):131–139.
[5] Attenborough K, Wright M, Umnova O. Mathematics summer schools for acoustics research training. The Journal of the Acoustical Society of America. 2012 Mar 1;131(3):2532–2538.
[6] Rieper A. The Architectural Manipulation of Sound: Architecturally Articulating Urban Space to Protect and Enhance the Outdoor Acoustic Environment. 2013 [cited 2019 Aug 27]; Available from: http://researcharchive.vuw.ac.nz/handle/10063/2682
[7] Hedblom M, Knez I, Ode Sang Å, Gunnarsson B. Evaluation of natural sounds in urban greenery: potential impact for urban nature preservation. R Soc Open Sci. 2017 Feb;4(2):170037.
[8] Bahram Soltani K. Application of Acoustic Comfort Criteria in Urban Planning and Design. Tehran: Iran Center for Urban Studies and Architecture; 1995.
[9] Academy of Persian Language and Literature. Searching the Academy Approved Words [Internet]. [cited 2019 Aug 27]. Available from: https://tools.wmflabs.org/farhangestan/results
[10] The Assiciation of Australian Acoustical Consultants. Acoustical Terminology [Internet]. [cited 2019 Aug 27]. Available from: https://aaac.org.au/Terminology
[11] Aletta F, Kang J, Axelsson Ö. Soundscape descriptors and a conceptual framework for developing predictive soundscape models. Landscape and Urban Planning. 2016 May;149:65–74.
[12] Westerkamp H. Exploring Balance & Focus in Acoustic Ecology. Journal of Acoustic Ecology. 2011;11(1):7–13.
[13] Levitin DJ. This Is Your Brain on Music: The Science of a Human Obsession. Reprint edition. New York, N.Y: Plume/Penguin; 2007. 322 p.
[14] Everest FA, Pohlmann KC. Master handbook of acoustics. 5th ed. New York: McGraw-Hill; 2009. 510 p.
[15] Rossing TD, Moore FR, Wheeler PA. The Science of Sound, 3rd Edition. 3rd edition. San Francisco: Pearson; 2001. 680 p.
[16] K. C. Pohlmann, Principles of digital audio, 4th ed. New York : McGraw-Hill, 2000.
[17] Zhang M, Kang J. Towards the Evaluation, Description, and Creation of Soundscapes in Urban Open Spaces. Environ Plann B Plann Des. 2007 Feb 1;34(1):68–86.
[18] Davis D, Patronis E. Sound System Engineering, Third Edition. 3 edition. Amsterdam ; Boston: Focal Press; 2006. 504 p.
[19] Qiabaklou Z. Fundamentals of Building Physics 1: Acoustic. Tehran: Jahad Daneshgahi (Amirkabir University of Technology); 2015.
[20] Featherstone M. The Flâneur, the City and Virtual Public Life. Urban Studies. 1998 May 1;35(5):909–925.
[21] Mohsen Haghighi N, Ghaleehnoee M, Ghaffari A. Assessing the Effective Elements of Acoustic Comfort and Soundscape Imageability of Users in the Naghsh-e-Jahan Square, Isfahan. Journal of Architecture and Urban Planning. 2018;10(19):133–52.
[22] Acun V, Yilmazer S. A grounded theory approach to investigate the perceived soundscape of open-plan offices. Applied Acoustics. 2018 Feb 1;131:28–37.
[23] Jeon JY, Hong JY, Lavandier C, Lafon J, Axelsson Ö, Hurtig M. A cross-national comparison in assessment of urban park soundscapes in France, Korea, and Sweden through laboratory experiments. Applied Acoustics. 2018 Apr 1;133:107–117.
[24] Yu L, Kang J. Modeling subjective evaluation of soundscape quality in urban open spaces: An artificial neural network approach. J Acoust Soc Am. 2009 Sep;126(3):1163–1174.
[25] A. J. Torija, D. P. Ruiz, and A. F. Ramos-Ridao, “Application of a methodology for categorizing and differentiating urban soundscapes using acoustical descriptors and semantic-differential attributes,” J. Acoust. Soc. Am., vol. 134, no. 1, pp. 791–802, Jul. 2013.
[26] Yang W, Kang J. Soundscape and Sound Preferences in Urban Squares: A Case Study in Sheffield. Journal of Urban Design. 2005 Feb;10(1):61–80.
[27] Acoustic Bulletin. Room acoustic descriptors [Internet]. [cited 2019 Aug 27]. Available from: https://www.acousticbulletin.com/room-acoustic-descriptors-rt-c50-and-gain
[28] Hornsby B. The Speech Intelligibility Index: What is it and what’s it good for? Hearing Journal. 57(10):10–7.
Naqshejahan- Basic studies and New Technologies of Architecture and Planning
Volume 9, Issue 4 - Serial Number 28
Winter 2020
Pages 287-304