Procedural urbanism Designing the Network City prof. J. Huang prof. R.Guargiani ass. G.Labelle
PDM 09-10 H. van Boetzelaer
postulate() The PDM firmly believes in the need for Architecture & city planning to design new means for spatial plannification. The presented project aims at proposing one type of alternative to masterplanning strategies whose central ambition is to [pre]-plan a [pre]-conceived final state of completion, deploying primarily two dimensional form of single-use urbanism.
thesis() the rise of the Network Society & the advent of the Information age
the network is the icon of the post-modern age. study object
As a starting point the study focused on one of the most perrenous element of cities and also the most vital one; the street network. Following the preliminary thesis, the focus of the study has been directed at the networks shaping the cities, as well as the flows animating them. The complexities of the latter has been reduced, by focusing on the most generic and spatial city shaper: the street network.
macro: increased connectivity & integration
micro: increased densification
centralised decentralisation
The socio-economical developments of the last century have seen the world develop in a networked infrastructure, with markets being tightly linked and integrated all over the world, leading the way for an extensive decentralisation of firms and good production. This has brought up new network of cities and
places, going beyond the geographical space. While on the global sacle the world networks has opted for a decentralised structure, on the micro scale, cities have emerged as key social attractors and reveal a very centralised organisation, in order to remain as competitive a
city.
Le Corbusier Plan Voisin for Paris - bringing suburbia to the
Vesnin brothers plan for the linear city - disurbanism and social condensers
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REX proposal for the SITRA low2no competition; two of the most important components of the strategy included a development guide book and a decision making toolkit.
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Recent city planning competition have seen the submitted proposals evolve into adaptive strategies and development guidelines rather than designed cities. Examples range from REX & ARUP plans for SITRA, ZHD architects plan for Kartal-Pendik, many of KCAP city planning projects and others.
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axis network
from design to strategy
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streets crossings OMA proposal for the Melun-Senart development, showcasing a strategy of the void by defining what should not be built rather than what should.
The resulting proposal usually takes the form of a guidebook showcasing potential applications of the conceived strategy. The latter are often presented more as a proof of concept than an actual “finished� design.
guideLines() As a response to the important changes (average building turnover, globalization) that have occurred during the past century, architecture and city planning have to search for new means of expression and planning.
focused on relationships reactive flexible
spaceSyntax() Space Syntax offers a theoretical frame, as well as a set of tools for the analysis of the role of spatial layout in shaping patterns of human behavior. It builds itself around Network analysis, considering the streets as the main elements rather than the each specific street corner. The emphasis is on the topological aspects of the Network’s graph, rather than it’s built typology.
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city map from city plan to axial map
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In order to use space syntax as an analytical tool, an axial map needs to be drawn by the analyst. This map is first and foremost already an interpretation of the city, a first analytical plan, if compared to “traditional� urban analysis method.
axial map
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streets crossings from crossings to axis network
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axis network
Space syntax is a methodology pioneered by Ben Hilier. It allows for the tures of a network’s graph, such as its depth, local integration, global integraevaluation of the city, by focusing on the street networks and the movement tion, connectivity. they create. One of the tools chosen for the study of the PAV is a further development of Hilier’s axial maps, developed by Lucas Figueiredo. This analytical method focuses on continuity maps rather than straight axis and allows for a better understanding of the network of given site, by outlining several key fea-
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Connectivity
Control
Depth
Global Integration
Local Integration
Fast Choice
The connectivity of a line ”i” is the number of lines “j” that directly intersect it
Control represents the degree to which a line “i” controls the access from and to the lines “j” directly connected to it.
Depth is the topological distance of a line “i” from a given line “j” through the shortest path between them. Each line in this path counts “one topological step”.
Integration is a measure of eccentricity, accessibility or centrality. It measures the topological accessibility of a line from the whole system. In other words, integrated lines are easily accessible from all other ones while segregated lines are poorly accessible.
The integration of a given line i can also be calculated for a subset of k’ lines which have depth from the given line less or equal to a given “radius” r. Note that the values for k’ and Dk’ may be different for each line in the system.
Choice is the number of times n that a line i is used in the set of all shortest paths from all lines to all other lines in the system. This measure is expressed as the probability of a line being present in this set of shortest paths.
Space Syntax allows for specific measure of a street network, by combining the analysis of it’s graph structure as well as its physical structure. The output is presented as several maps colouring each line according to their relative value. There’s one map for each measure, and their comparison and thorough lecture allow for an in depth and measurable analysis of a given site and street network.
Axial map of Barcelona, representing the local integration of each axis
syntax examples
Space Syntax allows for specific measure of a street network, by combining the analysis of it’s graph structure as well as its physical structure. The output is presented as several maps colouring each line according to their relative value. There’s one map for each measure, and their comparison and thorough lecture allow for an in depth and measurable analysis of a given site and street network.
Cities are places where information and material are integrated. cities as intation machines
This integration takes place on top of a changing infrastructure that is sometimes designed and sometimes organic. We can think of this infrastructure as a network, or, more accurately, as a set of overlapping networks, each with different distance measures between nodes. As a hypothesis, the project proposes, as a simplifying assumption, that city dwellers do have a common goal: the integration of information. Furthermore, that urban structures will tend to optimize this integration.
methodology() In order to be able to respond to the everchanging surroundings, economies and social needs, the project has been devised as a 2 steps growth strategy for evolving street patterns and built densities relating to the current state of the network.
connectivity
GI
depth
control
Connect (depth, control) Connect acts directly on the street network. The use of space syntax and a abstracted graph of the study network as indicators, a new street network is designed with the goals of increasing the system global integration and reducing the maximum control and depth.
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choice
FAR 1.0
FAR 3.0 FAR 1.5
FAR 2.0 FAR 2.0
FAR 0.5
GI 1.0 GI 1.2 GI1.5 GI 1.6
GI 1.75
GI 2.0
Densify (globalIntegration) The allowed built density is reworked, being defined by axis rather than by plot. Developing a diversified and constantly evolving built density, always related to their position in the system of the city.
GI 1.0 GI 1.5
GI 1.0
GI 2.0
Test(superSite, site) As a mean to test the validity of the methodology a site was chosen.
string superSite = «geneva»; A site in the city of Geneva was chosen to deploy the research, and framing the thesis in more specific issues in order to make emerge an open strategy. Geneva’s development has brought it to the tops of the world’s cities. However the lack of precise planning as to its expansion have led it to petrify itself, leading to an enormous housing crisis, as well as a lack of vision for its future.
connections long distance path network
connections territorial paths networks
connections settlement paths network 1
connections settlement paths network 2
social condensers
poulation per km2
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evolution of the amount of vacant housing
282,2 km2 surface
inhabitants
1847 inhabitants / km2 0
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453’439 467 vacant dwelling units
60 630 frontaliers per day
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the housing crisis
Geneva’s development was partly toggled by the implementation of the UN headquarters on the lake bank. The influx of capital, Governemental & non-Governemental Organisations have brought with them a steady immigration. This demographic growth was at first accompanied by a policy in building new housing. However, since the 80’s a severe housing crisis is hitting Geneva leaving the housing market with a mere 1% of vacant
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housing (for a market to be dynamic, 10% minimum are needed). Interestingly, the above map reveals most of the population is concentrated around the lake, leaving most of the Canton devoid of inhabitants, leading to massive daily exode.
Designing the Network City prof. J. Huang prof. R.Guargiani ass. G.Labelle
PDM 09-10 H. van Boetzelaer
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string site = «pav»; A site in the city of Geneva was chosen to deploy the research, and framing the thesis in more specific issues in order to make emerge an open strategy. Geneva’s development has brought it to the tops of the world’s cities. However the lack of precise planning as to its expansion have led it to petrify itself, leading to an enormous housing crisis, as well as a lack of vision for its future.
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THE SITE
The sector of the PAV was chosen, as it has been at the center of many questions regarding the development of Geneva’s city. Its status has remained vague from its inception in the 1900s. Its position on the city edge and its current very low density allow to build the hypothesis it could be a potential extension area for Geneva.
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THE SITE
The sector of the PAV was chosen, as it has been at the center of many questions regarding the development of Geneva’s city. Its status has remained vague from its inception in the 1900s. Its position on the city edge and its current very low density allow to build the hypothesis it could be a potential extension area for Geneva.
pav connections settlement
The current infrastructure network distributes the PAV in an uneven way, create discontinuities in the urban fabric, as well as too big city blocks to be experienced on foot, leading to very little to no pedestrian activity. The presence of the highway entrance/exit, divides the site vertically, and although it is lifted above the ground, the poor accessiblity of the space it covers attracts very little appropriation.
Its current form is mainly the result of the railway network rather than a true actor of the dynamics of the PAV.
pav connections long distance
pav connections territorial
pav connections settlement
topography
Until the 1900s, the PAV was relatively isolated due to the its floodable nature and the relative lack of hydraulic features: the Arve, the Drize and the Aire. It’s only with the drying up and redirecting of the latters that the site became constructible. Its topography also prevented the easy access to the plateau de Bernex and Lancy, thus defining the PAV as the “end” of the city. Hardly unveiling it as potential extension area of Geneva.
natural context
The late adjunction of the PAV to the rest of Geneva has only been well as determining where the future route des acacias was to be built. made possible with the canalisation of two affluents of the Aire as well as the regulation of the flow of the river, as before that, the area was regularily flooded and inhabitable, as well as unusable. The canalisation works, hand-built by workless men after the second world war in order to occupy them. The result have had a highly structural impact, resulting in a south-north axis : the route des Jeunes, as
construction date
80-09 60-80 40-60 20-40 xx-20
historical development
Although the train station was built before most of the present area. constructions on the PAV, the built growth was directed from the city to the station, as it normally happens with the introduction of a new hub. Rather it is as if the built mass grew from the train station to the city. First according to the axis generated by the rails in the lower part of the railway U-turn. Secondly in a patchwork way in the upper of the unfinished rail tracks above the route des Acacias, allowing for the apparition of a sport
bus depot
la B창tie woods Firmenich center ethnographic museum Firmenich center
TSR
Rolex headquarters bank Pictet de Rochemont
Vernets sport center bank UBS
GLOBAL
Uni Mail
Uni Mail
Rolex headquarters
free port free port
TSR
bank Pictet de Rochemont
Vernets barracks
Etoile parking goods train station
bank UBS
Uni Mail
REGIONAL
Etoile parking
Migros center
goods train station
bus / tram depot la B창tie woods Vernets sport center ethnographic museum
CITY (LOCAL)
shopping center la Praille
Migros center
bus / tram depot
Uni Mail
shopping center la Praille
bus / tram depot
social condensers
Some important element structure the site and its dynamic. Mainly oriented to mass market, they offer an existing infrastructure to the site, and participate to its current identity. However because of their client base, they do not offer any proximity opportunities, as they all connect to place much further away. Resulting in an increased traffic around them.
Vernets barracks
courtyard building
warehouses
rawhouses
single housing built context
The PAV surroundings offer a wide diversity in built typolgies very remote from one another and with out defined transitions. This allows for little readability of the site as an entity or made of mutlitple ones.. Witin the PAV, a very clear segmentation is revealed, with clearly sparated typological zones showcasing little diversity and no transition with its surroundings.
74% commercial activity
12% public
6% 4%
programatic distribution
mixed
housing
Although the train station was built before most of the present area. constructions on the PAV, the built growth was directed from the city to the station, as it normally happens with the introduction of a new hub. Rather it is as if the built mass grew from the train station to the city. First according to the axis generated by the rails in the lower part of the railway U-turn. Secondly in a patchwork way in the upper of the unfinished rail tracks above the route des Acacias, allowing for the apparition of a sport
density
34% 0.5-1.0
22% public domain 14% 0.0-0.5 44% 1.0-1.5 8% 1.5-2.0 8% 2.0-7.0
built density
The current built density of the PAV is a clear result of the master plan, allowing mostly industrial activites and aiming at selling the biggest plot possible, to accommodate the bigger industry buildings. The site reveals an avrage density of 1, which clearly opens up the possibility for intensivly densifying the area,.
Diagnostic:
CORNAVIN LES BAINS
PLAINPALAIS
QUARTIER DES BANQUES LANCY
CAROUGE
FRANCE
CONNECTIVITY
PLAN-LES-OUATES
to / from FRANCE / LAUSANNE globally connected
locally disconnected
The pav area situation as a left-over of the city is mainly due to the following points:
weaknesses: - globally connected but locally disconnected - monofunctional - loose built tissue - no typological diversity potentials: - city center extension - re-appropriation of Arve borders - densification
OCCUPATION
DENSITY
diagnostic round-up
no typological diversity lack of built cohesion
monofunctionnal
very low density loose urban tissue
GEOGRAPHY
clearly delimited by the Arve & the Lancy plateau & Carouge
physical proximity with current city centers
spaceSyntax(geneva)
geneva axial map
Runing the Mindwalk software on Geneva’s street network, several away in Bernex’s direction. key features emerge, highlighting Geneva’s main axis, it’s most lively areas, which propose an intrinsic network of both highly connected streets and vers local ones. One striking element also does emerge from the analytical continuity map, that is the potential axis running from one of Geneva’s main hub; Rive, all the way to the route des Acacias and through Lancy and further
geneva syntaxed global integration
more globally integrated
geneva syntaxed local integration
more locally integrated
geneva syntaxed connectivity
more connnectivity
geneva syntaxed depth
less deep
geneva syntaxed fast choice
more used
geneva syntaxed control
more control
geneva syntaxed length
longer length
spaceSyntax(pav)
pav syntaxed axial map
pav syntaxed global integration
more globally integrated
pav syntaxed local integration
more locally integrated
pav syntaxed connectivity
more connnectivity
pav syntaxed depth
less deep
pav syntaxed fast choice
more used
pav syntaxed control
more control
onSiteApplication()
makeModel(applet)
pav radial graph
In order to understand the hierarchy of the PAV network. This abstract model was built, inverting the realinonship of nodes and streets. It does so by showing each street as a node and all it’s direct connection (street crossing). The space syntax method basically works with the same graph model, although it replaces the evaluated data on the plan.
ID|X0|Y0|X1|Y1|NAME|CONNECTIVITY|CONTROL|DEPTH|FAST CHOICE|GLOBAL INTEGRATION|LENGTH|LOCAL INTEGRATION R2|LOCAL INTEGRATION R3|RADIUSRADIUS INTEGRATION|SINUOSITY 0|-43.70950809193618|1121.238078673227|519.43610186999|637.8866714971564||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|519.43610186999|637.8866714971564|770.1695538948788|422.6801377699248||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|770.1695538948788|422.6801377699248|943.9904176191204|-142.4465577960627||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|943.9904176191204|-142.4465577960627|1019.863412681264|-256.0361219999786||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|1019.863412681264|-256.0361219999786|1033.395924634369|-314.6470919223266||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|1033.395924634369|-314.6470919223266|1044.39829500397|-358.5867672783206||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|1044.39829500397|-358.5867672783206|1018.872935003063|-426.9833660062795||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|1018.872935003063|-426.9833660062795|997.7138407208313|-591.3606783397008||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|997.7138407208313|-591.3606783397008|948.6494374270396|-658.2640196196539||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|948.6494374270396|-658.2640196196539|902.0850794310674|-874.7277813232917||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|902.0850794310674|-874.7277813232917|900.5689382564169|-883.3800481035078||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|900.5689382564169|-883.3800481035078|890.375139092881|-904.6257858465791||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|890.375139092881|-904.6257858465791|869.9869952187864|-930.269475587096||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|869.9869952187864|-930.269475587096|848.513194191095|-954.7603756202184||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|848.513194191095|-954.7603756202184|785.7072304639022|-999.5761064373013||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|785.7072304639022|-999.5761064373013|724.5792518489479|-1031.495308678842||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|724.5792518489479|-1031.495308678842|-1.926863628980754|-1648.09402853176||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 0|-1.926863628980754|-1648.09402853176|-415.364338297235|-1945.64306919191||33.0|6.2596|0.0|0.3286|3.768|1.0|6.0446|4.6113|6.0446|4.2483 1|-129.2594903806939|-2240.874147531425|-111.462248585507|-2027.065054684313||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|-111.462248585507|-2027.065054684313|-50.24475669117691|-1779.39355653952||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|-50.24475669117691|-1779.39355653952|-21.95340078031313|-1665.505951158465||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|-21.95340078031313|-1665.505951158465|-43.63763424113767|-459.7965969862807||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|-43.63763424113767|-459.7965969862807|-74.79707460712687|-180.4900266158047||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|-74.79707460712687|-180.4900266158047|-55.96449438903528|841.0943475583207||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|-55.96449438903528|841.0943475583207|-56.73903527601123|866.4599158538093||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|-56.73903527601123|866.4599158538093|-72.14457736878649|922.1413748037558||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|-72.14457736878649|922.1413748037558|-63.73531770056615|1028.141222193681||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|-63.73531770056615|1028.141222193681|-42.36044090342057|1127.512315664445||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|-42.36044090342057|1127.512315664445|113.1204622365712|1356.879524840396||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|113.1204622365712|1356.879524840396|187.626870990638|1458.747541151601||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|187.626870990638|1458.747541151601|211.2647869414213|1490.400155694889||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175 1|211.2647869414213|1490.400155694889|220.1128704702478|1508.301106877209||18.0|6.2019|2.0|0.1776|2.6444|0.9423|4.9808|3.111|4.9808|2.1175
mindwalk xml output
After performing the analysis, Mindwalk allows for the export of an .xml file. The data in the xml contains all points of the axial map, as well as each value per continuity line. Unfortunately, it doesn’t allow for being called from another program, making a potential feedback loop highly painstaking.
connection parameters: distMax = new Param(50, 20, 2000).tag(«distMax»); Param distMin = new Param(50, 0, 2000).tag(«distMin»); Param minConnectivityParam = new Param(1, 1, 20, 1).tag(«minConnectivity»); Param
connectivity = new Param(25, 1, 25, 1).tag(«connectivity»); Param control = new Param(9, 0, 9).tag(«control»); Param depth = new Param(6, 0, 6, 1).tag(«depth»); Param length = new Param(1, 0, 1).tag(«length»); Param localIntegration = new Param(0, 0, 4).tag(«localIntegrationR3»); Param globalIntegration = new Param(3, 0, 3).tag(«globalIntegration»); Param
The meat of the project is about how one connect the dots of the evaluit’s about how ated system. Several questions arise as to how does one lead the evolution of a network. Towards what should it develop? we connect The software has as of now been developed to explore the different the dots meanings of the measures and their relationships in developing a new network pattern.
sameRouteCheck(currentNode, targetNode)) { if (distanceCheck(currentNode, targetNode) && connectivityCheck(currentNode, targetNode) && controlCheck(currentNode, targetNode) && depthCheck(currentNode, targetNode) && lengthCheck(currentNode, targetNode) && localIntegrationCheck(currentNode, targetNode) && globalIntegrationCheck(currentNode, targetNode)) { currentConnection.add(new Pts(currentNode, targetNode) if (
re-processing
.stroke(255, 0, 0));
model growth tendencies: Each street aims at being as globally integrated as possible with the minimum effort. by connecting to the closest streets that will allow the formation of the longest element. by connecting to the closest highly globally integrated street.
possibleGrowthScenario()
global integration
local integration
connectivity
global integration
depth
built hight per axis according to route global integration
potential step 1
local integration
control
choice
global integration
local integration
connectivity
global integration
depth
built hight per axis according to route global integration
potential step 2
local integration
control
choice
global integration
local integration
connectivity
global integration
depth
built hight per axis according to route global integration
potential step 3
The meat of the project is about how one connect the dots of the evaluated system. Several questions arise as to how does one lead the evolution of a network. Towards what should it develop? The software has as of now been developed to explore the different meanings of the measures and their relationships in developing a new network pattern.
local integration
control
choice
global integration
local integration
connectivity
global integration
depth
built hight per axis according to route global integration
potential step 4
The meat of the project is about how one connect the dots of the evaluated system. Several questions arise as to how does one lead the evolution of a network. Towards what should it develop? The software has as of now been developed to explore the different meanings of the measures and their relationships in developing a new network pattern.
local integration
control
choice
global integration
local integration
connectivity
global integration
depth
built hight per axis according to route global integration
potential step 5
The meat of the project is about how one connect the dots of the evaluated system. Several questions arise as to how does one lead the evolution of a network. Towards what should it develop? The software has as of now been developed to explore the different meanings of the measures and their relationships in developing a new network pattern.
local integration
control
choice
existing
projected streets
projected built heights
overlay
lastWords()
achieved learnings(): intuition as the main driving force computation is a tool not a project machine congestion == integration the city as a topological system? communication process the code is a project
further research(): path growth research such as frei otto’s work further investigation and refinement of space syntax communication process