Maryh
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Network Analysis of Streets
Analysis Stage prepared by, Berkay Gebitekin, Emma Poulton, Jakub Fraczek & Shinjini Basu Urban Design Studies Unit University of Strathclyde Glasgow
Booklet No.5
Introduc on For these 5 weeks, Group 5 have worked on the “Network Analysis of Streets� for Shawlands (Kilmarnock Road) in the South and Maryhill (Maryhill Road) to the North of Glasgow. Detailed study maps of the street networks for both the regions were generated by the help of computer so ware, Mompey and QGIS. These maps show the Betweenness, Closeness and Straightness Centrality of the two areas. The study of centrality has helped us understand how a city network func ons and to iden fy specific areas needing regenera on and redevelopment. With the help of this analysis, we aim to propose an altered scenario for each street that carefully shapes the growth of Greater Glasgow.
Authors Berkay Gebitekin
MSc in Urban Design, University of Strathclyde
Emma Poulton
Master of Architecture, University of Strathclyde
Jakub Fraczek
Master of Architecture, University of Strathclyde
Shinjini Basu
Master of Architecture, University of Strathclyde
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Network Analysis of Streets
Contents 01
Introduc on
02
Objec ves
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Methodology
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Technical Notes
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Network
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Centrality
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Modelling the Exis ng High Street Exis ng Layout
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Betweenness
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Closeness
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Straightness
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Depriva on
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03
Scenarios Overviews
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Scenario 1: Link
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Scenario 2: Bridge
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Scenario 3: Develop
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Conclusion Conclusion
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Bibliography
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01
Introduc on
This chapter will introduce city networks, centrality, and the so ware Momepy. 1.1 Objec ves 1.2 Methodology 1.3 Network 1.4 Centrality
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1.1 Objec ves
1.Using the density of centrality of the study area rela ve to the surrounding areas in the system to analyse the exis ng network poten al to sustain an ac ve and varied local life. 2.To develop alterna ve scenarios with the aim of understanding the impact of proposed changes to the network on the study area and its surroundings.
1.2 Methodology A er being introduced to the concept of mul ple centrality analysis (MCA) by our tutors, the first step was to understand the underlying ideas of the analysis by researching the papers wri en on the said subject. Impor ng the Greater Glasgow areas network map from h ps://digimap.edina.ac.uk, we performed 6 MCA analyses using the so ware “momepy� which are as follows; - Global / Local Betweenness - Global / Local Closeness - Global / Local Straightness The tests are performed by the so ware Mompy on the basis of edges and nodes of the network. The results are then assigned to each node and averaged onto edges from the two end nodes that define them. The resul ng map was then loaded into qGIS and given a color legend to be er visualise as; - Red = High - Orange = Medium/High - Yellow = Medium - Green = Medium/Low - Blue = Low From these results we determined mul ple areas for interven on and tested a variety of scenarios by making changes to the exis ng network and re-tes ng the modified maps. The results that showed the biggest improvement and impact were chosen to be presented as alterna ve scenarios for the network of the study area and its surroundings.
1.3 Technical Notes The Glasgow Area tests were performed with a map radius of 12km and were then clipped to a 10km radius to alleviate the unwanted edge eect. The study area tests were performed with a map radius of 5km and were clipped down to 4km for the same reason. The analysis radius parameter used in the local betweenness and straightness variants of the test were 1000 steps and in the closeness variant it was 400 steps.
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Booklet No.5
1.3 Networks The city connec vity can be easily analysed when presented as a network, which deals with the rela onship between the “nodes” and the “links/edges”. The nodes represent the street intersec ons and links represent the streets. The network of streets show how well or poorly a city is connected . An efficient network helps in shaping a well accessed city. This efficiency is determined by the centrality of the space.Centrality is associated with the movement of people in a certain area and it is determined by its three indices: Betweenness, Closeness and Straightness. Porta, S., Cruci , P., & Latora, V. 2008)
1.4 Centrality Betweenness Centrality: This is measured by how likely a par cular space in a city is probable to be passed through while travelling between the start point and the des na on (Porta, S., Strano, E., Iacoviello, V., et al. 2009)..
Closeness Centrality: This represents the shortest or the actual distance between two nodes. Closeness may be explained as proximity as well as how accessible a place is. The closer a place is to the other, the more accessible it is ( Porta, S., Latora, V., & Strano, E. 2010).
Straightness Centrality: This is derived from the idea that less deriva on of the shortest path between to nodes increases the efficiency of their communica on. In other words, it expains that, the straighter the path easier it gets to find places (Porta, S., Latora, V., Wang, F., et al. 2011).
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Global (Authors’ own, 2019)
Local (Authors’ own, 2019)
“Global” and “Local” are important terms in the street network analysis (Porta, S., Latora, V., Wang, F., et al. 2011). In the global scale, the mompey so ware considers every node within the system, which means each node is assessed with every other node with the en re map. For the local scale, a certain radius is fed to the so ware so that it works on assessing each and every node present with the radius. For example, in a 400 mm radius, every node in that par cular radius is assessed with every other by the system. Any distance can be set for the radius. Both these Global and Local maps represent closeness centrality.
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02
Exis ng Road Analysis
This chapter will introduce Kilmarnock Road and it’s exis ng centrality 2.1 Exis ng Layout 2.2 Betweenness 2.3 Closeness 2.4 Straightness 2.5 Depriva on
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2.1 Exis ng Layout
(Digimap,2019)
This map shows Maryhill Road as exis ng in the north of Glasgow. The study area stretches from the train sta on down to Tesco and is indicated above with a black line. The pink oval shows a 400 meter radius around the study area. The high street is lined with a variety of building typologies, heights, ages, and architectural styles. Shops, takeaways, empty plots, and a police sta on can be found along the high street. The 400 meter radius is home to residen al buildings, schools, churches, gyms, a library, and other ameni es. The street is poorly connected to some of the neighbouring areas due to the canal.
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2.2 Betweenness
Global (Authors’ own, 2019) As Maryhill road is surrounded by development areas that are ineec vely connected to itself and to each other, the results of the Global Betweenness map marks it on the higher end of the scale meaning it must be used for movement on its general axis (NW-SE) in the area.
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Local (Authors’ own, 2019)
The Local betweenness analysis demonstrates that there are a small number of main roads for the purpose of outside connec ons marked in red. There is also a lack of inner travel paths in the area as most developments are closed o to transit traďŹƒc.
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2.3 Closeness
Global (Authors’ own, 2019) The global closeness analysis demonstrates that the main city and human ac vity lies towards the southern direc on of the study area.
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Local (Authors’ own, 2019) The lack of areas marked in red (high closeness) throughout the study area, this analysis shows that this area has a deficiency of a well connected and dense street network. It can also be pointed out that for the en re length of Maryhill road itself there is only 1 area on the higher end of the scale, which is counterintui ve to the idea of a “High Street”.
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2.4 Straightness
Global (Authors’ own, 2019) As Maryhill Road used to be a connec ng road between Glasgow town center and Bearsden village, the global straightness map reflects this fact in the high straightness it assigns to the main road.
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Local (Authors’ own, 2019) The local straightness analysis shows that while the prevalent use of dead-ends and cul de sacks decreases the straightness of the area surrounding the study area, Maryhill Road itself is rela vely high on the scale in most parts.
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2.5 Depriva on
Map showing depriva on (Authors’ own, 2019)
Depriva on is measured using four dimensions to classify housing in the UK: educa on, health and disability, employment, and household overcrowding (Nomisweb,2019). A household may be deprived in non or one to four of these dimensions in any combina on. The map above uses these dimensions to asses the depriva on in areas around Maryhill, with dark blue represen ng areas with the least number of deprived households, and red represen ng areas with the most number of deprived households. This map shows a strong correla on between household depriva on and centrality as seen in the maps in the previous chapter. The areas of Maryhill around Maryhill Road and to the East show high household depriva on and also have low centrality, whereas the more central and be er connected southern area of the West End around Great Western Road show low levels of household depriva on (Scotland Datashine, 2019). While more factors would need to be assessed to determine how much of a connec on lies between household depriva on and centrality, the correla on between the two seen in this map helped to determine areas needing interven on and would suggest that a more central network around Maryhill Road could help improve the area in more ways than just access.
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03
Scenarios
This chapter will analysis alterna ve scenarios aiming to improve centrality 3.1 Overview 3.2 Scenario 1: Link 3.3 Scenario 2: Join 3.4 Scenario 3: Connect
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3.1 Overview Link: Maryhill has good link to Glasgow’s city centre, however there is no direct route to the West End to the south. Therefore such a link is proposed, to increase movement between those areas. It is also extended to the north and east. This scenario tries to exploit exis ng street network to the maximum, doing li le changes to current layout, introducing new links, bridges and intersec ons, to create con nuous link across the city.
(Authors’ own, 2019)
Bridge: There are several dis nc ve neighbourhoods on both sides of Maryhill Road, however they usually only have a single connec on with the high street and are not connected with each other. New bridge connec on proposed in this scenario aims to improve connec vity and therefore centrality of two of such neighbourhoods, opening them to the main road and centre of the area.
(Authors’ own, 2019)
Develop: The marked area is a large unused plot of land, separa ng other neighbourhoods and ac ng as a barrier to the high street character of Maryhill Road. This scenario will inves gate a situa on in which the area is developed with a regular network of streets.
(Authors’ own, 2019)
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3.2 Scenario 1: Link Betweenness
Global: Exis ng (Authors’ own, 2019)
Global: Alterna ve (Authors’ own, 2019)
Betweenness - lobal: The link introduced in this scenario turns several separated sec ons of hi h betweenness streets into a con nuous stretch. Maryhill’s central housin area near the intersec on of Maryhill Road and proposed cross-link has improved centrality as well.
Local: Exis ng (Authors’ own, 2019)
Local: Alterna ve (Authors’ own, 2019)
Betweenness - local: On local scale, proposed change brought moderate improvement in Maryhill area, but also posi vely affected area south of Kelvin River.
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Closeness
Global: Exis ng (Authors’ own, 2019)
Global: Alterna ve (Authors’ own, 2019)
Closeness - lobal: Althou h a sec on of proposed link to the north of Maryhill Road has lower centrality value, it has increased for the area west from it.
Local: Exis ng (Authors’ own, 2019)
Local: Alterna ve (Authors’ own, 2019)
Closeness - local: The alterna ve scenario shows no change compared to current case in Maryhill area, however closeness of certain area south of Great Western Road has improved significantly.
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Straightness
Global: Exis ng (Authors’ own, 2019)
Global: Alterna ve (Authors’ own, 2019)
Strai htness - lobal: Proposed link increased only sli htly strai htness of few secondary streets in Maryhill centre, however it had posi ve impact on roads on the eastern ed e of study area and to the south of Great Western Road.
Local: Exis ng (Authors’ own, 2019)
Local: Alterna ve (Authors’ own, 2019)
Straightness - local: On the contrary to the aim, alterna ve scenario has visibly lower local straightness on Maryhill Road and in Maryhill area than original case.
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3.3 Scenario 2: Bridge Betweenness
Global: Exis ng (Authors’ own, 2019)
Global: Alterna ve (Authors’ own, 2019)
Betweenness - lobal: Introduc on of the brid e and intersec on with Maryhill Road created a link of hi hest centrality score oin throu h the areas that were previously disconnected.
Local: Exis ng (Authors’ own, 2019)
Local: Alterna ve (Authors’ own, 2019)
Betweenness - local: On a local scale, the implementa on took away centrality from the high street and distributed it to nearby streets.
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Closeness
Global: Exis ng (Authors’ own, 2019)
Global: Alterna ve (Authors’ own, 2019)
Closeness - lobal: The nei hbourhood to the east of the canal ained the hi hest centrality score over the exis n case, as the hi hest lobal closeness zone extended.
Local: Exis ng (Authors’ own, 2019)
Local: Alterna ve (Authors’ own, 2019)
Closeness - local: On a local scale, proposed link had only a slight impact on nearest streets, as it connects areas of low original closeness.
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Straightness
Global: Exis ng (Authors’ own, 2019)
Global: Alterna ve (Authors’ own, 2019)
Strai htness - lobal: The nei hbourhood to the east of the canal has overall improved from least central to second-to-least, however at the cost of a sec on of Maryhill Road north-west from the intersec on loosin one de ree of centrality, therefore makin the outcome ques onable.
Local: Exis ng (Authors’ own, 2019)
Local: Alterna ve (Authors’ own, 2019)
Straightness - local: Impact of the proposed change on local straightness is negligible, with only some shortest sec ons of streets to the south and north of the intersec on showing any change.
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3.4 Scenario 3: Develop Betweenness
Global: Exis ng (Authors’ own, 2019)
Global: Alterna ve (Authors’ own, 2019)
Betweenness - lobal: Proposed development shows a network of hi h betweenness. The link to the south over Kelvin River also created an important way throu h.
Local: Exis ng (Authors’ own, 2019)
Local: Alterna ve(Authors’ own, 2019)
Betweenness - local: On a local scale, proposed development has a medium score on betweenness. It also affects the area to the east, which has sec ons of lower centrality in the alterna ve scenario.
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Closeness
Global: Exis ng (Authors’ own, 2019)
Global: Alterna ve (Authors’ own, 2019)
Closeness - lobal: The area inves ated in this scenario lies ri ht between lower and hi her lobal closeness zones, however in the alterna ve case those zones are extended sli htly to the north.
Local: Exis ng (Authors’ own, 2019)
Local: Alterna ve (Authors’ own, 2019)
Closeness - local: In local closeness analysis, the development that was introduced remains at low centrality. This may be due to the street network having much lower density than areas of West End that were included in wider simula on area.
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Straightness
Global: Exis ng (Authors’ own, 2019)
Global: Alterna ve (Authors’ own, 2019)
Strai htness - lobal: This alterna ve development scenario improved visibly lobal strai htness of wider area around the interven on, with hi her centrality scores appearin on streets to the north-west, south-west, south east, and in the interven on area itself.
Local: Exis ng (Authors’ own, 2019)
Local: Alterna ve (Authors’ own, 2019)
Straightness - local: On a local scale, the straightness of proposed development scheme ranges from above average to high. Also sec on of Maryhill Road next to it and to the south gained a score compared to the exis ng scenario.
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Conclusion
While the altera ons made in the previous chapter do not obviously improve the centrality of Maryhill road, they do improve the surrounding network and connec vity to neighbouring areas. The decision to link Maryhill road down to Great Western Road and Argyle Street oers the people an easier way to travel south whereas before the best op on is to travel east to the city centre and then back again. By crea ng bridges from Maryhill road to the neighbouring areas over the canal, more op ons are given to encourage people on the other side of the canal to use the high street regularly and improve centrality to these areas. The development to the north of Maryhill Road has improved overall centrality in that area as well as giving a much needed makeover to the exis ng empty land by the high street. A con nua on of this study would most likely look at improving the centrality of Maryhill Road itself. As discussed above, the altera on scenarios used in the previous chapter have helped to improve the centrality of the overall neighbourhood network but had li le eect when looking just at the high street. Maryhill has had a diďŹƒcult city planning history consis ng of tearing down whole areas and rebuilding, so this study could be con nued by focusing on these areas where the networks created have li le harmony with the high street.
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Network Analysis of Streets
Bibliography Digimap. (2019). Retrieved November 16, 2019, from h ps://digimap.edina.ac.uk/? clid=IwAR2ybNIrH9uQI9aP_ rIxQQF1H5CH2JGrZ7gBdnCKEyl70BJpUFYrwfzwmZo Nomisweb. (2019). h ps://www.nomisweb.co.uk/census/2011 Porta, S., Cruci , P., & Latora, V. (2008). Mul ple centrality assessment in Parma: a network analysis of paths and open spaces. URBAN DESIGN Interna onal, 13(1), 41–50. h p://doi.org/10.1057/udi.2008.1 Porta, S., Latora, V., & Strano, E. (2010). Networks in Urban Design. Six Years of Research in Mul ple Centrality Assessment. Network Science, 107–129. h p://doi. org/10.1007/978-1-84996-396-1_6 Porta, S., Latora, V., Wang, F., et al. (2011). Street Centrality and the Loca on of Economic Ac vi es in Barcelona. Urban Studies, 49(7), 1471–1488. h p://doi. org/10.1177/0042098011422570 Porta, S., Strano, E., Iacoviello, V., et al. (2009). Street Centrality and Densi es of Retail and Services in Bologna, Italy. Environment and Planning B: Planning and Design, 36(3), 450–465. h p://doi.org/10.1068/b34098 Scotland Datashine. (2019). h ps://scotland.datashine.org.uk/#table =QS108SC&col=QS108SC0007&ramp=RdYlBu&layers=BTTT&zoom=12&lon=4.2407&lat=55.8559 All Mompey Maps have been generated by
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