Islamic- Iranian Cities
Abbas Ghaffari; Morteza Mirgholami; Bita Shafaei
Abstract
Highlights- Spaces such as Rasteh-Bazaars, which are identical in form and material, exhibit consistent acoustical behavior.- By decreasing sound intensity, sonic comfort does not necessarily increase.- In tranquil urban spaces, with the occurrence of "Difference in SPL", the tranquility and quality ...
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Highlights- Spaces such as Rasteh-Bazaars, which are identical in form and material, exhibit consistent acoustical behavior.- By decreasing sound intensity, sonic comfort does not necessarily increase.- In tranquil urban spaces, with the occurrence of "Difference in SPL", the tranquility and quality of the soundscape decreases.- Simply following the standard values of SPL and RT is not enough for sonic comfort.- The environmental characteristics and qualities of spaces such as geometric proportions have a direct effect on pleasantness of the soundscape. IntroductionSoundscape is a subfield of urban studies that deals with the quality of sound heard and perceived in urban spaces. Numerous characteristics affect the quality of urban space soundscapes, and the acoustic behavior of the space is thus an influential factor which depends on its environmental characteristics. The acoustic behavior of the space indicates that the physical body of any environment amplifies or attenuates sound waves in the face of sound. As the environment body intensifies sound once created in space, sound waves stay in the environment longer, and increase sound intensity. Conversely, when the acoustic behavior of space attenuates, sound waves are destroyed in space shortly after created by sound sources. In this case, the intensity of the sound heard in the environment can be relatively stable, provided that the audio sources are constant.Theoretical FrameworkThe amount of time it takes sound to drop to 60 decibels after created by a sound source is called Reverberation Time (RT), which is measured in seconds. In soundscape studies, Sound Pressure Level (SPL) is also a physical component in decibels, which is used to measure sound loudness. Thus, Sound Pressure Level and Reverberation Time are two components that can specify the acoustic behavior of a space. In addition to acoustic assessments, soundscape studies address how people perceive the sounds around them and how desirable and pleasant they are. In fact, acoustic measurements are a tool that can help to create the desired soundscape, because sonic comfort depends to a large extent on the SPL. However, what greatly matters in soundscape studies is the perceptual loudness and subjective sonic comfort. Therefore, it is necessary to clarify the factors affecting these subjective components. The perceptual quality of urban soundscape is specified through subjective assessments.MethodologyThis research discussed the effect of environmental features on the acoustic behavior of Rasteh-Bazaars, in Tabriz Grand Bazaar, and on the quality of the soundscape therein. Based on the objective evaluations, the acoustic behavior of the Rasteh-Bazaars and the factors affecting it were specified, and the desirability of the Rasteh-Bazaars soundscape was clarified using subjective evaluations. Objective assessments were made to specify the acoustic behavior of the Rasteh-Bazaars based on the measurements of SPL and RT. The B&K 2260 set of equipment and ACAM100 acoustic camera were used to measure RT and SPL. Both of these values were evaluated in frequency spectra. Subjective assessments were made based on a descriptive soundscape questionnaire, where a total of 165 people answered the questions. The questionnaire assessed sound loudness, sonic comfort, sound preferences, and soundscape descriptors through the Likert scale. Based on the results, it could be found how the people present in the Rasteh-Bazaars of Tabriz Bazaar felt about and perceived the space soundscapes.Results and DiscussionThe findings demonstrated that spaces such as Rasteh-Bazaars, which are identical in form and material, exhibited consistent acoustic behavior. If accompanied by physical changes such as ones in the space axis and spatial integration as cavities, this homogeneity could change the acoustic behavior and the heard sound. This finding could add a new concept called homogeneous spaces to the field of soundscape design. This means that homogeneous urban paths can be designed so that the soundscape is perceived almost uniformly along them, and diversity and distinction can be provided through physical changes in the urban soundscape that can be perceived during movement. The findings also indicated that sonic comfort did not necessarily increase as sound intensity decreased. Even in tranquil urban spaces with low SPLs, the tranquility and quality of the soundscape decreased as the phenomenon of difference in SPL occurred. This important finding demonstrated that a new component called urban soundscape clarity should be evaluated in the study of soundscapes in tranquil urban spaces to investigate the occurrence of difference in SPL in tranquil urban spaces.ConclusionBased on the comparison of the objective and subjective findings of the research, it was found that it was not sufficient for provision of sonic comfort to simply follow the standard values of SPL and RT. This is because the phenomenon of difference in SPL could have a negative effect on environmental and sonic calmness, as mentioned earlier, in a silent space. The subjective perception of the soundscape depended on factors other than the physical quantity of the sound. In fact, the values of SPL and RT, which indicate the acoustic behavior of the space, could not serve as the sole basis for assessment of the quality of the soundscape although somehow involved in people’s perceptions thereof. The environmental characteristics and qualities of spaces, such as lighting and congestion and supplied goods appeal at the Rasteh-Bazaar were found to have direct effects on the favorability of the soundscape.AcknowledgmentThis article was extracted from Bita Shafaei’s doctoral thesis under the supervision of Dr. Abbas Ghaffari and Dr. Morteza Mirgholami at Tabriz Islamic Art University.
Urban Design
masoumeh ayashm; morteza mirgholami
Volume 5, Issue 19 , August 2016, , Pages 69-80
Abstract
Abstract
The concepts of place and sense of place have attracted many contemporary researchers in the field of urban design and planning. In the past, cities had a higher ability to establish connection between humans and space. Today, however, cities consist of many spaces without identity and meaning ...
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Abstract
The concepts of place and sense of place have attracted many contemporary researchers in the field of urban design and planning. In the past, cities had a higher ability to establish connection between humans and space. Today, however, cities consist of many spaces without identity and meaning which are produced through a process of homogenization emerging from capitalist urbanization. The production of non-places and identical spaces has marginalized the identity of local places and cultures. By using inconsistent pattern with the site context, only human's temporary needs will be resolved and regardless of place concept and a sense of place, urban spaces are formed in cities. Promotion of placelessness is the only feature of this kind of urban spaces making.
This research, by studying the fundamentals of place and the sense of place, examines the question of whether an integrated urban street has a unique sense of place in all its small parts such as its sequences. Through a critical review of different place features and models for evaluation of sense of place, a new model was synthesized. This model was then been used to analyze a case study in Urmia city (different sections of Imam Khomeini Street). Division of Emam Khomeini Street to different parts are based on people’s mental images and perception of this street. Three methods were used for analyzing this urban space. In the first method, according to the writer's field observation and final model ( presented in this study), Emam Khomeini street was analyzed. In the second method, results of the questionnaire based on some spatial words that describe the quality of urban spaces were presented. In the third method, parts of Emam Khomeini Street were analyzed using land use maps and land use distribution patterns. According to the findings, different parts of Imam Khomeini Street have different identities and thus create different senses of places. in addition, the amount of land use vitality in these parts of Emam Khomeini Street supported this fact.based on the results of this study, the amount of contribution of each parts are determined according to four factors (perceptual, physical, social and functional) presented in the model. Using this item can identify which aspect needs to be upgraded or modified in each section. In other words, the overall framework for improving urban spaces is clarified. In the third sequence, perceptual, physical and social factors and in first sequence, functional factor should be modified, and these amendments can improve spatial integration.
The research method used was descriptive-analytical using various methods such as library study, documentation and presence in the environment and questionnaire for data collection (field observations and questionnaire design and interviewing). The results of the study confirm the hypothesis that different sections of Emam Khomeini Axis have different impacts on people’s sense of place and meanings of the street.
