Type Of Urban Form Research Articles

What kind of cities are more conducive to haze reduction: Agglomeration or expansion?

The realization of high-quality development in the future in China would depend on whether cities, the carriers of China's economic transformation, can create a “win-win” situation in which economic agglomeration and green emission reduction policies are achieved. From the perspective of agglomeration economy theory, this study identified three types of urban forms of 286 prefecture-level cities in China by using night light data, and systematically investigated the effect of urban forms on haze pollution and its influencing mechanism. The research obtained the following findings: (1) under the current level of economic development, higher economic density, a more compact urban form, and a more concentrated single-center mode could effectively reduce particulate matter (2.5) concentration; (2) the mechanism analysis showed that a high-density, single-center or compact urban form plays a role in “haze reduction” by optimizing industrial structure, improving traffic accessibility, and improving the innovation level of enterprises; and (3) further analysis showed that the larger the city size, the easier it would be to cluster the “haze reduction” effect, and it was easier to cluster the “haze reduction” effect in the case of eastern cities than central and western cities.

Energy Planning and Urban Form: Solar Energy as a Design Parameter in Ouargla, a Southern City in Algeria

Energy planning plays a crucial role in the built environment, particularly when aiming at reaching sustainable cities. Today, most researchers are focusing on exploring the accurate potential of renewable energies. However, few studies have explored the correlation between urban forms and renewable energy inputs. The objective of this paper is to examine the relationship between the incident solar irradiation, urban form and the potential of photovoltaic energy at a local level. The study focuses on the case of the city of Ouargla, which is located in southern Algeria. In terms of methodology, it adopts three main steps. Firstly, three different types of urban form have been identified according to three main criteria (morphology of streets and lot, buildings use and environment). Secondly, numerical simulations were performed based on 3D models of these urban forms, with the purpose of evaluating the distributions of solar irradiations on the different building roofs, which helps to determine the most appropriate urban form for solar energy use. The study demonstrates that urban form has an impact on solar energy potential, which means that the latter provides a significant increase in the photovoltaic energy production.

Effects of Urban Forms on Separate Drainage Systems: A Virtual City Perspective

The development of urban drainage systems is challenged by rapid urbanization; however, little attention is paid to the urban form and its effects on these systems. This study develops an integrated city-drainage model that configures typical urban forms and their associated drainage infrastructures, specifically domestic wastewater and rainwater systems, to analyze the relationship between them. Three typical types of urban forms were investigated: the square, the star, and the strip. Virtual cities were designed first, with the corresponding drainage systems generated automatically and then linked to a model herein called the Storm Water Management Model (SWMM). Evaluation was based on 200 random configurations of wastewater/rainwater systems with different structures or attributes. The results show that urban forms play more important roles on three dimensions of performance, namely economic efficiency, effectiveness, and adaptability, of the rainwater systems than of the wastewater systems. Cost is positively correlated to the effectiveness of rainwater systems among the different urban forms, while adaptability is negatively correlated to the other two performance dimensions. Regardless of the form, it is difficult for a city to make its drainage systems simultaneously cost-effective, efficient, and adaptable based on the virtual cities we investigated. This study could inspire the urban planning of both built-up and to-be-built areas to become more sustainable with their drainage infrastructure by recognizing the pros and cons of different macroscale urban forms.

Examining Trade-Offs between Social, Psychological, and Energy Potential of Urban Form

Urban planners are often challenged with the task of developing design solutions which must meet multiple, and often contradictory, criteria. In this paper, we investigated the trade-offs between social, psychological, and energy potential of the fundamental elements of urban form: the street network and the building massing. Since formal methods to evaluate urban form from the psychological and social point of view are not readily available, we developed a methodological framework to quantify these criteria as the first contribution in this paper. To evaluate the psychological potential, we conducted a three-tiered empirical study starting from real world environments and then abstracting them to virtual environments. In each context, the implicit (physiological) response and explicit (subjective) response of pedestrians were measured. To quantify the social potential, we developed a street network centrality-based measure of social accessibility. For the energy potential, we created an energy model to analyze the impact of pure geometric form on the energy demand of the building stock. The second contribution of this work is a method to identify distinct clusters of urban form and, for each, explore the trade-offs between the select design criteria. We applied this method to two case studies identifying nine types of urban form and their respective potential trade-offs, which are directly applicable for the assessment of strategic decisions regarding urban form during the early planning stages.

Future energy use and CO2 emissions of urban passenger transport in China: A travel behavior and urban form based approach

Work on comparing cities in terms of their transport energy consumption and CO2 emissions in the urban passenger transport sector has rarely been done using detailed travel activity data that takes into account city level differences in terms of economic development, population, and urban form. A personal activity based approach is necessary to better reflect travel behavior change results from different social, economic, urban form, technical, and transportation policy situations in the future. The present study extends the existing activity, modal share, energy intensity, fuel/carbon intensity (ASIF) modeling framework by disaggregating travel activity into key structural components and city-specific factors for 288 prefectural level cities in China. Testable econometric modeling systems were built to link mode split and mode specific travel distances with local economic and urban form characteristics in four different population sizes and two urban form types, based on 187 travel surveys in 108 Chinese cities in the past two decades. Scenarios of energy use and carbon emissions between 2010 (baseline) and 2050 were developed. Results showed that in 2010 urban passenger road transport in China generated 396 Mt CO2 emissions and per capita urban passenger transport energy use increased as city size expanded. By 2030, under business as usual scenario assumptions, energy use in the urban passenger transport sector comprised 23.2 Mt of gasoline, 1.72 Mt of diesel, 3.36 billion M3 of natural gas, and 0.62 billion kWh of electricity. While national policies targeting travel behavior change have been shown to mitigate emissions to some extent, urban transport policies targeted at specific spatial and temporal drivers of energy demand and emissions may be more effective in meeting policy goals. Short-term policies that promote car-pooling and ride sharing and medium-term policies that increase the cost of driving and promote public transport (such as transit oriented development, walkable neighborhood design, and parking pricing/restraint in city centers) help stabilize carbon emissions over the long term. However, the decision of building polycentric cities might have less significant impact on mitigating urban passenger transport in big cities. Moreover, large-scale promotion of electric vehicles should be designed from a long-term perspective rather than from a short-term one to achieve balanced carbon emissions in regard to the decarbonization process of electricity generation in China.

Adapting Design Principles of Traditional Courtyard Housing for Future Urban Design

Most cities in recent decades have copied the modern type of architecture and urban design of the western countries. Modern cities in different regions of the world have been relatively developed with similar urban form types. In this research, it has been suggested to investigate the traditional or vernacular architecture and to propose new design principles based on the historic shape of cities. Thus the paper has been concentrated on vernacular architecture of traditional Iranian cities. The research has been focused on analysing the vernacular architecture of this country and to define the main traditional design principles in scale of urban fabric particularly in residential neighbourhoods. These principles have been adapted to be applicable for the contemporary life style and condition of the Iranian cities. The design proposal has been assessed via an inquiry by design process in order to understand the feasibility and adequacy of the suggested design principles. This research can show the methodology of learning from the traditional architecture and urban design to make new distinctive urban forms. Such urban forms create distinguished local identity for Iranian residential urban fabrics.

Modeling of urban form against sand accumulation in the city of Gourara in southern Algeria

In our present research, we focus on the modeling of airflow related to extreme weather events and natural disasters, such as sand accumulation, with urban form studies. The objective is to find which urban form can promote sand passing and reduce as much as possible stagnation of sand in the built environment (streets, alleys, etc.). The urban form design is discussed through the numerical simulation of airflow. We simulate the airflow behavior, especially the wind velocity, which is responsible of sand stagnation in some specific configurations. Various configurations of buildings were considered and different airflow behaviors were thus observed. The method of modeling was verified by following some best practice guidelines. In this study, a correlation was made ​​between wind velocity and morphological parameters such as width of buildings and widths of the street that separates buildings, building height and building density. Results of our simulations show that some types of urban form can promote wind speed and help blow away the accumulated sand in the city.

Automobile-dependency as a barrier to vision zero, evidence from the states in the USA

With a traffic fatality rate of 10.6 per 100,000 as of 2013—more than triple that in the UK, the Netherlands, and Sweden—the United States has the worst traffic safety performance of all developed countries. Statewide variations are even more pronounced. North Dakota registers more than twice the national average and five times the rate of Massachusetts. We used panel models and annual data from 1997 to 2013 to capture the effect of seven separate sets of factors that influence traffic safety: exposure, travel behavior, socioeconomics, macroeconomics, safety policies, and mitigating factors such as health care. The results of our panel models and supplementary analysis of state effects show that two variables — Vehicle Miles Traveled and Vehicles per Capita—have the strongest impact on traffic fatality rates. This is closely followed by Infant Mortality Rates, the proxy that we used to represent the quality of health care. Policy levers such as Graduated Driver’s Licenses (GDL) have improved safety, but to a limited extent. We also found that states with higher urban density and more walking are associated with lower traffic fatality rates. Taken as a whole, our findings suggest that if additional progress is to be made in reducing traffic fatalities, emphasis needs to move beyond simply focusing on policies such as GDL and seat belt laws, which have already been adopted by almost all jurisdictions across the United States. We need to also consider factors that focus on the type of urban form that we are creating to ensure that we are fostering environments that encourage multi-modal transportation such as walking to reduce the VMT and Vehicles per Capita, the two strongest predictors of traffic fatalities.

Mapping urban form and function at city block level using spatial metrics

This paper focuses on the potential of urban metrics describing the presence and the configuration of built-up and open space areas for mapping distinct types of urban form and function at city block level. Next to traditional, patch-based metrics used in landscape ecology, alternative metrics are proposed, measuring the presence and the spatial arrangement of built-up and open space areas along a set of radial transects, along contours parallel to the urban block boundary and along the block's perimeter, as well as metrics describing the internal composition of the built-up area. Use of the proposed metrics for identifying different types of urban form and function was tested on the Brussels Capital Region. Large-scale vector data was used to define built-up structures and to analyse the morphological properties of the built-up area at block level. Decision tree classification was applied in conjunction with bootstrap aggregation to gain insight in the distinctive character of the defined metrics, and the robustness of land use and urban form classification based on these metrics. Our study points out the shortcomings of traditional landscape ecological metrics for mapping urban form and emphasizes the need for alternative approaches for analysing urban landscapes, more explicitly describing the morphological characteristics of the urban fabric.

Influence of urban forms on social sustainability: A case of Guwahati, Assam

In the last decade, the rapid growth of cities and exacerbated social problems have led to a great deal of inquiry on the extent to which the physical forms of cities can contribute towards achieving a just and sustainable future. Past investigations in the western context have remained less than satisfactory, further raising concerns about their applicability to the developing world cities which face essentially different urbanisation challenges and socio-cultural shifts. As India prepares itself to become an urban majority by 2050 and gives shape to its futuristic smart cities, there is clearly a pressing need to develop stronger empirical evidence about the influence of urban forms on social sustainability which links to sustainable design, policies and practices. This research therefore, tests the effects of urban forms on six aspects of social sustainability using both, qualitative and quantitative strategies, which are calibrated and validated for Guwahati, the dominant city of Assam in India. The quantitative findings for two urban form types using six case studies show that neighbourhood forms with connected and integrated street network, higher proportion of accessible open recreational spaces, higher mix of uses, higher densities and smaller compact urban blocks display higher levels of social sustainability amongst its residents, after controlling for intervening variables. Qualitative findings for four urban form types using twelve case studies further illuminate this complex relationship at the scale of block-segments. It highlights five key theories: (i) intervening variables, (ii) spatial proximity, (iii) favourable spatiality, (iv) complementing synergies and (v) tipping point.

Form and urban change – An urban morphometric study of five gentrified neighbourhoods in London

Research in Urban Morphology has long been exploring the form of cities and their changes over time, especially by establishing links with the parallel dynamics of these cities’ social, economic and political environments. The capacity of an adaptable and resilient urban form to provide a fertile environment for economic prosperity and social cohesion is at the forefront of discussion. Gentrification has emerged in the past few decades as an important topic of research in urban sociology, geography and economy, addressing the social impact of some forms of urban evolution. To some extent, these studies emphasize the form of the environment in which gentrification takes place. However, a systematic and quantitative method for a detailed characterization of this type of urban form is still far from being achieved. With this article, we make a first step towards the establishment of an approach based on ‘urban morphometrics’. To this end, we measure and compare key morphological features of five London neighbourhoods that have undergone a process of piecemeal gentrification. Findings suggest that these five case studies display similar and recognizable morphological patterns in terms of their built form, geographical location of main and local roads and physical relationships between street fronts and street types. These initial results, while not implying any causal or universal relationship between morphological and social dynamics, nevertheless contribute to (a) highlight the benefits of a rigorous quantitative approach towards interpreting urban form beyond the disciplinary boundaries of Urban Morphology and (b) define the statistical recurrence of a few, specific morphological features amongst the five cases of gentrified areas in London.

Evaluation of Compaction Index to Achieve Sustainable Urban Development Using AHP: Two Case Studies

The search for an ideal city, which can express both technological advantages and healthy spirit of rural life based on enlightening ideas of social justice, has long been the major concern of most philosophers, social reformers, writers, architects and urban planners. Urban form is known as a source of environmental problems. The emergence of "sustainable development" as a common term has raised many discussions on urban forms. Different types of urban forms (corridor, compact, marginal and edge) have been evaluated for sustainable urban development. It is revealed that compact city is more sustainable than other forms. There is disagreement on potential effects of compaction. Using archival studies, surveys and questionnaires, the author evaluates the environmental sustainability of Yousefabad as a dense neighborhood, compared to Garnet Hill, by AHP to prove that compaction alone cannot bring the expected advantages. To achieve advantages of compaction in urban design, the author emphasizes that four basic criteria of compact city, density, sustainable transportation, mixed land-use and diversity, should be interrelated.

The typology of the American metropolis: monocentricity, polycentricity, or generalized dispersion?

ABSTRACTAlthough the spatial structure of employment in large US metropolitan regions is a well-researched topic, few studies focus on medium-sized and small US metropolitan regions. Consequently, there is no overall typology relating small-to-medium urban form to employment distribution. We address this gap by investigating the spatial structure of employment in 356 metropolitan regions. We conceptualize six typologies based on three categories that have overlapping properties: “monocentricity,” “polycentricity,” and “generalized dispersion.” The study has three main findings. First, the three types of urban form that we identify as “hybrid” outnumber the three “pure” types by almost four to one. Second, job dispersion is a dominant characteristic in almost 70% of all metropolitan statistical areas (MSAs) (including the hybrid types), and polycentricity (56.7% of MSAs) is somewhat more common than monocentricity. Third, there is a strong relationship between population size and density. The population of medium-sized metropolitan areas is generally more dispersed than that of small and large metropolitan areas. Polycentricy emerges mostly in large metropolitan regions, while monocentrity is found in both small and large metropolitan regions.

The hutong urban development model compared with contemporary suburban development in Beijing

This paper assesses the traditional hutong street system and siheyuan courtyard house as an urban development model in contemporary Beijing by comparing it with the practiced alternative. Official government standards are used as criteria for measuring the performance of the urban form types. Criteria derived from government documents emphasise the efficiency and low-carbon emission of the transportation system and efficiency in land use, via higher densities. Minimum site areas devoted to green space are also specified. We compared the use of land resources in a sample of 9 hutong areas with those of a sample of 22 newly built communities. We collected traffic data and interviewed residents in these areas. We also examined transportation as a user of urban land, as well as the implications for land resources if the 2002 conservation plan is fully implemented. It was found that the hutong development models underperform with regard to building density depending on form type, but achieve much higher population densities than suburban housing. Motor traffic infrastructure in contemporary development takes up 3 times as much of the development area as the hutong do in their development area. The hutong outperform the rest of the urban fabric with regard to sustainable transport with 0.17 of the car mode proportion for all of Beijing. There is heavy dependency on three-wheeled vehicles for goods transport and high levels of walking. Moving the remaining population of the hutong as planned would require about 1800 ha of new residential land more than 30 km from the city centre.

Cities and Energy: Urban Morphology and Residential Heat-Energy Demand

Our aim is better understanding of the theoretical heat-energy demand of different types of urban form at a scale of 500 m × 500 m. The empirical basis of this study includes samples of dominant residential building typologies identified for Paris, London, Berlin, and Istanbul. In addition, archetypal idealised samples were created for each type through an analysis of their built form parameters and the removal of unwanted ‘invasive’ morphologies. The digital elevation models of these real and idealised samples were run through a simulation that modelled solar gains and building surface energy losses to estimate heat-energy demand. In addition to investigating the effect of macroscale morphological parameters, microscale design parameters, such as U-values and glazing ratios, as well as climatic effects were analysed. The theoretical results of this study suggest that urban-morphology-induced heat-energy efficiency is significant and can lead to a difference in heat-energy demand of up to a factor of six. Compact and tall building types were found to have the greatest heat-energy efficiency at the neighbourhood scale while detached housing was found to have the lowest.

A new type of urban form? Possible futures for fabric structures in urban contexts

This article explores possibilities for future uses of inflatable and fabric architecture in urban contexts. Such uses may serve regeneration or homeless sheltering purposes, drawing from the Bedouin and Traveller traditions. They may also build on the much more recent Western precedents offered by the “Occupy” movement and pop-up buildings, and arguably follow in the footsteps of Situationism.

Integrated irradiance modelling in the urban environment based on remotely sensed data

The complexity of built form and land cover has often limited detailed model estimates of solar irradiance in the urban canopy. These limitations arise largely from difficulties in generating contiguous detailed spatial representations of solar obstructing features such as buildings and trees. This study presents a method that integrates remotely sensed datasets across spatial scales for estimating irradiance in urban areas. The method draws largely on airborne Light Detection and Ranging (LiDAR) technology with specific focus on estimating radiation transmission through urban vegetation. The incoming irradiance above the urban canopy is determined using atmospheric transmission derived from geostationary satellite imagery to provide a long-term record of seasonal fluctuations in cloud cover, and the associated direct and diffuse irradiance. Individual model components are analyzed for three urban study areas to assess the interactions between input model parameters and patterns of different urban form. Results indicate that representations of trees as opaque objects substantially underestimate solar irradiance across urban form types, demonstrating up to a 18% underestimate of direct irradiance in treed residential areas. Both atmospheric transmittance and urban form are also shown to be critical model parameters, and are discussed with reference to unique considerations for generating estimates of urban irradiance.

Structure Analysis of Xuanfu in Ming Dynasty

This paper picks Xuanfu one of the military towns in the “Nine frontiers” as an example to research the defensive space along the Great Wall of Ming Dynasty. Analyzes space-defensiveness of Xuanfu town from some different points of view, such as the stratagem intention of location、function setting、urban form evolvement and spirit imago. Analyzes the historical causes of the town’s space, summarizes the space characteristic of military town a typical type of urban form and the influence of the special history background.

Land Use, Transport, and Carbon Futures: The Impact of Spatial Form Strategies in Three UK Urban Regions

Land-use and transport systems are an important determinant of carbon dioxide emissions from urban regions. It is often asserted that urban compaction is the spatial policy best able to constrain travel and emissions, but evidence supporting this assertion is limited, particularly with respect to the combined emission from transport and land use. Here, using land-use–transport interaction models, a residential dwelling type model, and transport and emission models, we forecast and assess carbon dioxide emissions from transport, dwellings, and commercial space to 2031 for a range of spatial strategies realistically investigated for three English regions of decreasing size (the Wider South East region, Tyne and Wear, and Cambridge). Our results reveal that compaction can reduce emission relative to other spatial scenarios but that the differences are small, about 5% between extremes, an order of magnitude less than emission growth observed over the trend period. Form has more influence for settlements where the pattern and proximity of employment, housing, and services can make cycling, walking, and public transport provision more feasible. We conclude that pricing and technology measures offer better prospects for combating the growth in carbon emissions of urban regions, but that the type of urban form delivered is likely to be a significant determinant in the type of clean energy technology that can be implemented.

Flows from early Modernism into the Interior Streets of Venturi, Rauch and Scott Brown

In 1972 the famous diagram of the ‘Decorated Shed’ was introduced into the architectural discourse; it implied a definition of ‘architecture as shelter with decoration on it’ [1]. The diagram was part of urban research into the commercial environment of Las Vegas that was interpreted by the researchers – Robert Venturi, Denise Scott Brown and Steven Izenour – as ‘a new type of urban form’ that they meant ‘to understand’ in order ‘to begin to evolve techniques for its handling’. Yet the critique on this and other research and designs by Venturi, Rauch and Scott Brown focused essentially on questions of form and more specifically of the image of architecture.