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Sprawled City; Lesson 15

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Urban Analysis
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URBAN
ANALYSIS
• This
refers to a process of
rationalizing urban planning and
design by investigating the form of
urban areas, theories of city
structure, and location as factors in
urban development.
• It
entails investigation of basic
urban frameworks, and concepts
and tools for analysing and
understanding urban problems.
• The scope of problems investigated
may include: economics (macro and
micro) and urban sociology.
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• Urban analysis may apply the following methods/data sources:
• Land use and density mapping;
• Data gathering survey methods;
• Geographic information systems;
• Journal/library sources.
• Urban analysis is interested in a complex and multi-layered
understanding of the city…’
• By
building a conceptual framework that acknowledges that
multiplicity through different pathways to sustainable development.
These pathways often co-exist and function concurrently within a
single city.
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KEY ISSUES AND RESPONSES IN URBAN ANALYSIS
• Urban Patterns/trends and their implication
• Zoning and the need for proximity
• Mobility/migration
• Compaction and the need for variety/richness of a place
• Suburbanization and the issue of urban sprawl
• Problems triggered by urban forms
• Unsustainable levels of resource use
• Inequitable lifestyles
• Ecological footprints: the catchment/amount of land necessarily
affected to enable everyday life of a city; the nature & extent of effects
of cities on land/environment.
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• a
measure of the share of
resources consumed by a city in
a region or a country……
• a basis of calculating allowances
for consumption and emissions
(ref. Global environmental space
calculation)
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1.
Shift from singular to multiple models of a sustainable city
• Questions the over-reliance and emphasis on compact city model as
a universal approach to achieving sustainability.
• Could constrain and blind efforts by researchers and policy-makers in
searching sustainable urban futures.
• Variety
in
choice
of
urban
form
based
on
local
situations….”Multiplicity”: a variety of approaches considered to suit
particular settlement types….of different scales and locations.
• Consider alternative scenarios and incremental change as opposed to
New Towns approach/wholesome change….consider constraints of
space, cost, and acceptability.
• (ref. to pros and cons of the compact city model)
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2.
Rejection of simplistic use of models, instead
develop competing pathways to sustainable cities
• Models not to be used as straightforward deterministic blue-prints to be
translated into reality through physical planning and design policies in a
series of linear stages
• Models to be used in a much softer, more flexible fashion: conceptual not
specific; to sensitize on different visions to a sustainable city
• Models to consider views and strategies of different urban actors with
competing social, political, and commercial interests.
• Actors views and strategies may resonate or dissonate with the visions of
particular models of development
• Need to understand how the changing social organization of urban
development may promote particular pathways towards distinct urban
futures.
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3. Co-existence of diverse sustainable urban futures within
a single city
• Charting
the multiplicity
sustainable urban futures
of
pathways
towards
different
• Examination of tensions and similarities between pathways:
different social assumptions and biases
• Broadening the range of determining factors of sustainability of
urban form: travel & fuel consumption; effects on ecology,
wildlife, and natural resources; effects on social conditions and
well-being etc.
• Adoption of inclusive approaches to avoid “islands” of success
stories amid “seas” of failures.
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4. Strengthening morphological studies
• Address size, mix of uses, block structures etc.
different scales of urban form – from the dwelling to
neighbourhood, zone, district, city, and region
• Explore
• Determine the key tangible and practical impacts of theoretical
models…achievable in real terms.
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• Urban form - Structure Analysis
• Character Analysis
• Spatial Analysis
• Socio-spatial analysis
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There are various classifications on this subject but generally all
taxonomies touch on key issues:
• Urban space efficiency;
• Typologies of built form;
• Transport and infrastructure efficiency;
• Environmental efficiency;
• Socio-economic and cultural considerations.
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• This looks at the alternative
shapes and structures of
cities that could guide desired
(sustainable)
development.
Analysis of urban form can
broadly be divided into macro
and micro scales.
• Macro-Urban Forms:
• The emphasis has mainly
been on functional qualities
that depend on overall form
and development pattern of
the city;
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• They will address at a larger scale:
• Different typologies of housing forms;
• Good environmental conditions;
• Access to open spaces for recreation and other functions;
• Adaptability to changing needs and socio-economic conditions;
• Access to country-side.
To classify city forms on the above accounts will require accurate data
on:
• Overall densities
• Total area required
• Minimum and maximum distances, etc.
• The data is generated using different theoretical city models e.g.
input-output model. Evaluation of models is done based on criteria,
standards, and performance values.
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THE KEY MACRO-URBAN FORMS:
• Dispersed City: portrays continued low-density suburban development
of population, housing, and jobs; infrastructure investment dominated
by road development. Encourages urban sprawl and loss of prime
agricultural and countryside land.
• Compact City: portrays increased population and density of an inner
group of suburbs, with associated investment in public transport
• Edge City: portrays increased population, housing densities, and
employment at selected nodes within the city; increased investment in
orbital freeways linking the edge cities.
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• Corridor City: focuses growth along linear corridor emanating from the
central business district (CBD), supported by upgraded public
transport infrastructure
• Fringe City: arises from additional growth predominantly on the fringe
of the city.
• The above macro-forms translate into various identifiable geometries;
these include:
• The core city/urban core
• The Star city/radial city
• The satellite city/Stellar pattern
• The Urban galaxy
• The Linear City
• The Polycentric City
• (ref. BUR 202 notes for definitions, merits and demerits of each of the
above)
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• These are based on interrelationship of people, transport
and amenities; they address the degree of user-friendliness
in terms of mobility and access to services and facilities
within walking and cycling distance and by public transport.
Micro-urban forms cover a number of component areas:
• Various neighbourhood types, including digital Sustainable
neighbourhoods, as envisioned in the Urban Villages
Movement, seek to rediscover the balance between housing
growth with the development of a strong and broad-based
local economy. The main features include:
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• A vibrant mix of uses: working
areas; higher density housing;
predominantly residential areas
• A hierarchy of open spaces:
neighbourhood central square;
pocket play parks; toddlers’
greens; riparian/canal corridors
• Integrated
transport system:
main bus/tram/light rail route;
local bus route; neighbourhood
street; local distributors; access
roads
• Local facilities: shops; primary
schools; places of
community facilities
worship;
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Various types of neighbourhoods include:
• Inner urban neighbourhoods: older suburbs with older housing
stock, mostly done by local authorities
• Modern
Suburbs: usually of mixed high- and low- rise
development mostly undertaken by private developers/building
societies or housing authorities e.g. NHC.
• Urban Extensions: new neighbourhood areas currently planned
on the edges of existing built-up areas.
• Brownfield Sites: Large sites of at least 20hectares in a single
ownership where the building structures have been identified for
clearing to pave way for new neighbourhood development.
Mostly where the original use has ceased e.g. disused railway
yards.
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• Digital villages address the needs of the society while taking
advantage of advancement in Information and communication
technologies (ICT)
• Neighbourhood Structure studies often address the following:
• Neighbourhood unit structure – overall, generalisation of key features
• Neighbourhood pattern e.g. transit system; home-work distribution
• Neighbourhood Elements:
 Street pattern types
 Block types
 Infrastructure types: lot scale; block scale; neighbourhood scale
 Frontage types
 Building types
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Transects
A transect is a system of classification deploying the rural-to-urban
continuum to arrange in useful order the typical elements of urbanism.
The elements may broadly be classified hierarchically as falling under:
• Urban core; urban centre; general urban; suburban; rural reserve; and
rural preserve.
• Clusters: These are agglomerations of neighbourhoods integrated by
shared infrastructure and amenities e.g. public transport system;
together they could form a regional urban centre. Cluster model
favours high density areas.
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Townscape And City Image
• Townscape refers to the collective view of the relationship of the
elements that create the town environment: buildings, trees, cars,
water, traffic, squares, advertisement and signage etc.…
• It is about optics, about places, and about content and their
weaving to create the overall town image. Townscape is about
underlying visual relationships that evoke a broad range of
human response.
• Image of the city is the mental picture a person constructs of the
parts of a town based on physical relationship between those
parts….it a collective picture of what people extract from the
physical reality of the town. …expressed in form of an “impression
map” or “image map”. Use is made of basic elements as
conceptualised by Kevin Lynch: path, edge, node, district,
landmark (ref. BUR 202 notes)
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Degree of containment of development
Population density relative to land needed
Viability of public transport
Dispersal of vehicular traffic
Viability of mixed uses
Access to facilities and services
Access to green open spaces
Environmental conditions 9noise, pollution, congestion)
Potential for local autonomy
Potential for self sufficiency
Degree of adaptability
Image ability of the city (physical entity) as a whole
Image ability of parts of the city (neighbourhoods, districts, towns)
Sense of place and centrality
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