Sezione I – Il tema
spaces that integrate the elevated highway and their surrounding environments [Irizarry, 2003; Akinci et al., 2016]. In the recent decade, more studies and urban planning projects have incorporated the revitalization and redevelopment of urban spaces under the elevated structures [Jaffe, 2017; Anuar et al., 2017a]
especially in landscape architecture and urban design and planning [Bauer et al., 2011]. These subjects are mostly included in redevelopment, revival, and regeneration urban planning studies [Irizarry, 2003;
Akinci et al., 2016].
A comprehensive review of the related literature shows that there are some points that require more investigation. For example, the qualities of lost spaces under urban highways have not been fully addressed, especially in terms of focusing on citizens’ preferences and perceptions [Anuar et al., 2017b].
Most studies are instead focused on the experts’
opinions. Moreover, although many environmental designers are addressing lost urban spaces, current literature does not include an effective body of research focused on developing countries, which have more complicated issues regarding this problem. Therefore, It is necessary to investigate the environmental qualities of such urban places with a focus on local preferences and opinions [Trancik, 1986; Anuar et al., 2017a]. In this regard, this paper responds to the need for running more empirical-based studies in this field. The findings of such studies could lead to an improvement of the existing situation, and also help devise guidelines for future developments.
Additionally, construction of elevated urban free-ways and the multi-level bridges in Iran have been on an increase, while not enough studies are run as to identify their effects on urban fabrics and the surrounding spaces thereof. This calls for running more sample-driven studies in this field to diagnose the existing situation and assess the consequences. The findings of such studies not only would lead to improving the existing situation but also devise guidelines for future developments. As such spaces have great potential of being retrieved to alive urban areas. Moreover, with
respect to the essence of the public domain and its effect on different dimensions of urban life, the urban space quality of mega-cities like Tehran is on a rapid degradation. In cities which spaces under the elevated roads have caused complex issues in urban areas, addressing this problem is more important. Urban studies should consider reclamation and revival strategies toward conquered cities based on the values and traditions of their own cities and priorities of their contemporary users.
The modern urban constructions change the traditional city space configuration or result in inefficiency and distance them from the routine urban city life cycle [Razaghi Asl et al., 2014]. Among all the urban spaces the intermediate abandoned spaces under urban highways and bridges are of major concern which has been converted into neglected spaces in the urban area.
This research aims to analyze the problem of leftover spaces of elevated highways in public urban spaces of Iran. According to the question, what peoples’
preferences should be considered in order to reclaim the urban elevated highway to places with high levels of satisfaction? The findings will result in a list of qualities for designers to consider for improving environmental qualities in places under elevated highways. The research is done in a public urban space under Niayesh highway in Tehran, the capital city of Iran. Therefore, the objective of the study is to assess the characteristics of spaces underneath elevated highways based on available literature as well as to explore the proposed solutions for planning approaches.
This research is done in 3 sections as follows; (1) In the first section the characteristics of places under elevated highways and people’s preferences for environmental qualities are identified through reviewing literature; (2) A qualitative method is used to analyze the environmental qualities based on peoples’ preferences. In this regard, the quality of spaces underneath the elevated highway is measured by desk study. Then, users’ perception is analyzed by
Fig. 1. These figures are some samples of lost urban spaces under bridges and elevated highways (Carmona 2010).
applying a qualitative method to create vital spaces enhancing the social interaction of residents in lost spaces. Investigating the users’ preferences and public opinions highlighted some qualities such as safety and security, physical coherence, visibility, vitality, richness, sense of appropriation and comfort.
Incorporating these qualities in the planning process provides opportunities to have a better use for spaces under the elevated highways and bring some new ideas to explore the utilization of leftover spaces; (3) Finally, in the third part, design principles related to extracted dimensions are discussed in more detail for improving the quality of these urban spaces.
Lost Spaces
Public life and public space were historically treated as a cohesive unit in comparison to rapid modernism’s large-scale planning.Industrialization and modernization of cities have resulted in dysfunctional public spaces and an emphasis on pedestrian scale and residential communities at the expense of city life.
Gehl believes it is critical to develop contemporary tools that can be used analytically to improve the quality of life between buildings and megastructures [Gehl et al., 2013].
Trancik [1986] coined the term “lost space” to describe public spaces that need to be redesigned, anti-spaces that have no positive impact on their surroundings or users. He argues that the blame for leaving lost spaces is related to cars, urban renewal, privatization of public space, functional separation of uses, and finally the Modern Movement [Trancik, 1986].
Carmona mentions two types of organizations in the classification of contemporary urban spaces: (1) over- managed spaces, leading to space calibration and homogenization, (2) the under-managed spaces increasing the poor designing [Carmona, 2010].
According to Carmona, spaces under the urban bridges and elevated highways are considered as an under-management type of urban spaces. He believes that under-management urban spaces lead to neglected, invaded, exclusionary, segregated spaces which require improvement of environmental quality [Carmona, 2010].
In order to improve the quality of the environment, Tibbalds advocated the use of good design as a means to solve the problems of declining the quality of public space across the world. He also argued that public space is too often littered, piled with rotting rubbish, covered in graffiti, polluted, congested and choked by traffic, full of mediocre and ugly poorly
maintained buildings, unsafe, populated at night by homeless people living in cardboard boxes, doorways and subways and during the day by many of the same people begging in the streets [Tibbalds, 2012].
Besides, the Project for Public Spaces (PPS) claims four basic factors for measuring the appropriateness of public spaces including access and linkage, comfort and image, uses and activities, and sociability [PPS, 2017]. PPS is an American organization which describes successful, or high quality, spaces as those that address issues of accessibility, activity and use, comfort and image, and sociability. That is, they are easy to access and connected to the surrounding community; contain a range of activities for a variety of users; feel safe, clean, and attractive, with adequate seating; and most importantly, act as venues for people to interact socially [De Girolamo, 2012; PPS, 2017].
Gehl emphasizes that life between buildings and urban structures is a dimension of architecture that requires more careful treatment. These places are locations where social interaction and perception, urban recreation, and the sensory experience of city life take place. Social interaction comprises the entire spectrum of human activities in public space including the necessary, the optional and the social types of behaviors [Gehl, 2011].
The contemporary approach tries to design how the leftover spaces have been transformed into vibrant spaces [Hauck et al., 2011]. For instance, to reclaim the lost space under highways and bridges, Souma conducted a thorough analysis of the impact of elevated highways in the urban areas. Her findings revealed six impact types: (1) Symbol of progression, increasing accessibility and mobility; (2) Dominant structure in urban fabric; (3) Segregating community or neighborhood, becoming physical and psychological barrier and visual intrusion; (4) Producing undefined space often misused; (5) Allowing minimum natural lighting and poor ventilation at space under the elevated structure and (6) Generating negative spaces or lost spaces which always been neglected [Souma, 2008]. Moreover, the poor physical condition of this type of space highlights this fact that it is rarely obvious as who should manage these spaces after they are built [Hajer, 2001].
An initiative in New York City titled “under the elevated”
created an innovative program to manage and enhance space under elevated structures. After noticing that there are over 700 miles of elevated structures in New York that often offer mobility to people riding vehicles and darkness to streets below them, the project reintroduced the spaces under the elevated structures
into community assets [Caroline et al., 2015].
Redesigning and revitalizing spaces under the elevated highways with activities can increase property values, offer better access to retails and shops, eliminate informal uses, increase safety and offer long term amenities for the communities. These assets are defined as buildings or other land which are mainly in actual use for the social, well-being or social interests of the local community which include parks and open green spaces; sports and leisure centers;
libraries; theatres; museums or heritage site and other similar public spaces serving to the community [OSS, 2019]. The project focused on local markets to revive economic activities and increase community assets and values. In this case, galleries and public spaces, sound-absorbing panels and vertical gardens are used to reduce noise, air pollution and other environmental impacts [Caroline et al., 2015].
Irizarry stated that highways have different effects on surrounding urban areas including physical, social and psychological, visual environmental, land use, economic conditions, displacements, and safety [Irizarry, 2003]. He ultimately considered factors such as identity, land use, architecture, and landscape in redesigning these lost spaces [Irizarry, 2003]. In another study, prominent strategies were introduced to basic design elements of the under-highway places as access, safety, lighting, management, programming, physical connection to the adjacent communities, visual complexity, nature, noise and air pollution, use of the structure and openness of the site [Biesecker, 2015].
The study of Razaghi and Onsori in Iran identifies the problem of places under urban bridges, and points out the potential of spaciousness of overpass bridges through three main parameters: (1) Location, important for presence and participation of people especially encountered when located at the intersection of important urban streets; (2) Physical form, defined by elements such as ceiling, floor, wall, shelter for stopping, and (3) Land use. In addition, they addressed the environmental impacts of air pollution and noises by suggesting two strategies of applying absorbing materials and green space planting [Razaghi Asl et al., 2014].
As a result, some theorists believe that the disappearance of the role of public spaces and lack of paying attention to the role of pedestrians is the product of the modern city and the need to redesign lost urban spaces is one of the crucial needs of the contemporary city. However, urban planners and designers have played an essential role in creating such unmanaged
spaces. In other words, the lack of proper functioning of a space is the result of a lack of paying attention to designers and planners to its users when designing.
The question in this regard is whether it is possible to revive the lost urban spaces with special attention to the environmental preferences of the users of a space and use the potential of these spaces to promote the social dimension of the city or not.
Users’ preferences
This study has been carried out using a qualitative method in order to explore the users’ preferences.
Therefore two main techniques of in-depth interviews and visual quality assessment method (Q-Sort) were used. Because of the complex interactions between people’s preferences and the growing body of design knowledge, more studies have focused on environmental psychology [Larson et al., 2015; Lak et al., 2018]. The results of this qualitative technique for analyzing the residents’ perception can be useful for designing urban spaces under elevated highways and bridges [Fig. 2].
Niayesh Highway of Tehran, Iran
This study assesses the effects of the development of the Niayesh elevated highway. This highway is
Fig. 2. The diagram illustrates the methodology of the study.
claimed as one of the most important highways in Tehran [Urban Planning and Architecture Department of Tehran, 2017]. Niayesh highway is a new-built expressway for connecting the northern-central part of Tehran to the west part. It starts from ValiAsr Street and is recognizes as Abshenasan expressway after an interchange with Ashrafi Esfahani expressway. In fact, Niayesh highway was constructed to facilitate mobility in a west to the east axis. However, these developments adversely affected the travelling demand in Niayesh highway and made it fully congested [Urban Planning and Architecture Department of Tehran, 2017] [Fig. 3].
Niayesh highway has caused extra challenges for adjacent residential neighborhoods. Noise nuisance, air pollution, undesirable views, and reduction in resident’s safety and security are some of the instants, and socio-economic challenges are some of the
long-term negative impacts of elevated highways. These spaces require designing projects to address these issues and transforming to active and vibrant urban spaces.
The diversity of these urban spaces, the important location of the highway in the main part of the city, the considerable length and different residential neighborhoods around it are important factors to attract more attention to this highway [Fig. 4].
Interview and visual qualities classification methods
A qualitative study has been conducted to understand people’s preferences to reclaim lost spaces by in-depth interviews and Q-Sort from August to November 2016.
The method of visual qualities classification (Q-Sort)
Fig. 3. Tehran, Niayesh Highway.
Fig. 4. Tehran, Niayesh Highway as a main horizontal transportation axis.
was first used by Stephenson [1953] in psychological science [Brown, 1996]. Today, this technique is used as one of the most common measurement techniques in various studies, such as measuring people’s opinions, planning, and environmental design.
n the Q-sort method, the judge or evaluator is given a set of statements or items previously developed or fixed upon [Zube et al.,1974]. In Q-sort or the method of visual quality classification, questions are asked to survey the preferences of people, such as completing the sentence “what I like...” [Kaplan, 1977]. This method stands in its own right as a valuable scaling technique, with no necessary relation to factor analysis or other similar statistical analysis [Block, 1961].
The simple random sampling is applied for interviewing with 50 people for maximum diversity in aging and gender until data saturation. We have used data saturation measures for the validity and reliability of the sampling procedure for interviews with residents.
Saturation of data is a term in qualitative research, mostly used in the grounded theory approach or other data extraction methods [Mason, 2010].
Theoretical saturation in this research is used means that researchers reach a point in their analysis of data that sampling more data will not lead to more information related to their research questions. These people have been living and working in neighborhoods near a newly-built highway called Niayesh in Tehran.
The socio-demographic status of all participants is represented in Table 1 [Fig. 5].
The Niayesh highway has created a lot of leftover and lost spaces in adjacent neighborhoods. In-depth interviews began with a general question of “what would you like to have under the elevated highways in order to use this space? And then it has been addressed to their needs and expectations. Interviews ranged in length from 20 to 35 minutes, with an average
duration of 25 minutes. Raised questions during these interviews have been presented in Table 2 [Fig. 6].
(Q-Sort) was used to validate the results of in-depth interviews. So, four sets of photographs – taking into account different qualities of designed spaces on A4 pages – were shown to identify the expectations of the people for desirable spaces under the elevated highway and bridges (Table 3) [Fig. 7].
The participants were asked to arrange the photos from their highest priority to lowest preferences, according to their daily or weekly space use. Interviews were transcribed and extracted into thematic categories by the members of the research team. Interviews carried out by two urban design partners, have been analyzed to enhance the validity and reliability of the qualitative research. The extracted data from the Q-Sort technique were grouped into seven categories providing the content of the questionnaire as the survey instrument. Ethical consideration has also been observed in writing without mentioning the names of the individuals with their consent.
Fig. 6. (Table 2) In-depth interview questions in qualitative research phase.
Fig. 5. (Table 1) Socio-demographic characteristics of the interviewees.
Content Analysis: People Preferences
The content analysis revealed that the most important feature that the majority of people mentioned was the lack of safety and security especially at night, due to the absence of adequate lighting, existing dark and hidden corners and fear of street harassment and cars. The second issue is the lack of attention to the visual aesthetics. For instance, concrete materials in the construction of elevated highways have led to impassable spaciousness. In most cases, after the construction process, the structure has been abandoned without any arrangements for aesthetics aspects for pedestrians.
By applying the Q-sort technique, the visual preferences of people were extracted. As shown in table 4 [Fig. 8], four groups of photos were chosen and shown to the participants to prioritize their preferences and expectations. These preferences were analyzed and then categorized in different urban design qualities (Table 4) [Fig. 8].
In case of expectations, participants have emphasized on lighting and public art strategies such as bright
colors, colored tiles, and planting. People are asked why no design principles are considered for enjoying the waiting time, although spaces under elevated highways have been sometimes used as public transit stations for high-speed buses or other transportation systems. Finally, the results of in-depth interview and Q-Sort methods are summarized in terms of design preferences (Table 5) [Fig. 9].
Rigor
The results of the content analysis studies should be trustworthy and processes used to obtain the results should be evaluated. Therefore, several methods are used to increase the credibility of data.
The prolonged engagement of the researchers with data gathering and the research process helped the researchers to be aware of participants’ culture and living conditions.
The researchers asked one expert who concurrently was involved in a qualitative project to analyze some parts of data as peer check, the resulting analysis showed that there are not any major differences
Fig. 7. (Table 3) Q-sort technique to explore residents’ preferences of under elevated highways spaces.
between this analysis and the researchers’ process (peer check) [Glass et al., 2009].
The data and their interpretations were checked and confirmed by participants (member check) [Graneheim et al., 2004].
Moreover, this study has been approved by the ethical committee of the Tehran Municipality House.
In addition, participants were informed that they could leave the study at any time. Recording interviews were conducted only with the consent of the participants.
Participants’ information was anonymous and marked with the code.
Discussion
The focus of this research is on the lost spaces under
The focus of this research is on the lost spaces under