During the last decades, our view of cities has been deeply transformed by new approaches combining engineering and complexity sciences. Network theory is playing a central role, facilitating the quantitative analysis of crucial urban dynamics, such as mobility, city growth or URLanization . In this framework, betweenness, a well-known centrality measure, represents a fundamental tool, standing out as a proxy of traffic density and congestion , among others . In this work, we focus on the spatial aspects of congestion.  To help unveiling such relationship , we introduce a simple model composed of a grid connected to a set of trees . This structure, coined as the GT-model, allows us to analytically describe in terms of betweenness, how and why congestion emerges in particular geographical areas , and more importantly, how it may co-evolve with city growth and mobility pattern shifts. We observe the emergence of several congestion regimes, with abrupt transitions betwenn them, related to the entanglement of arterial and urban local roads. The existence of these transitions is corroborated in a large amount of real city networks, thus representing an important step towards the understanding and optimization of traffic dynamics over coupled transportation networks.
During the last decades, the study of cities has been transformed by new approaches combining engineering and complexity sciences. Network theory is playing a central role, facilitating the quantitative analysis of crucial urban dynamics, such as mobility, city growth or urban planning . In this framework, betweenness, a well-known centrality measure, represents a fundamental tool, standing out as a proxy of traffic density and congestion . In this work, we focus on the spatial aspects of congestion. Analyzing a large amount of real city networks, we show that most cities present a set of congestion regimes, separated by abrupt transitions. To help unveiling this spatial dependence of the betweenness , we introduce a simple model composed of a grid connected to a set of tree graphs . This structure, coined as the GT-model, allows us to analytically describe in terms of betweenness, how and why congestion emerges in particular geographical areas of monocentric cities. The model predicts the emergence of several congestion regimes, with abrupt transitions between them, related to the entanglement of arterial and urban local roads. The existence of these regimes and transitions is in agreement with the multiple abrupt phase transitions found for real cities, and represents an important step towards the understanding and optimization of traffic dynamics over coupled road networks.
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our view
the study
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deeply
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URLanization
urban planning
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, among others
A
Analyzing a large amount of real city networks, we show that most cities present a set of congestion regimes, separated by abrupt transitions.
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such relationship
this spatial dependence of the betweenness
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trees
tree graphs
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, and more importantly, how it may co-evolve with city growth and mobility pattern shifts. We observe
of monocentric cities. The model predicts
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betwenn
between
R
transitions is corroborated in a large amount of real city networks, thus representing
regimes and transitions is in agreement with the multiple abrupt phase transitions found for real cities, and represents
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transportation
road