Compositional route types: Bridging configurational and urban tissue analysis

In the context of the ongoing debates about the effects of vehicular traffic on urban environments, interest in street networks has increased across a broadening range of disciplines. With that increasing interest, there has been a proliferation of analytical methods and measures. A potential solution is to combine measures with types of urban tissue, seen as a common point of reference. The issue then arises that the definition of urban tissue is no less prone to proliferation of methods and attributes to consider. This paper proposes a general-purpose set of route and route aggregate types as a basis for the differentiation of street networks to facilitate comparative analysis, including correlations between network and urban tissue analysis as well as correlations with other aspects and attributes of human settlements. The method used starts with the abstraction of minimum topological attributes of streets, set within the mereological framework of the compositional hierarchy of built form, to arrive at a set of minimum elements. Possible combinations of the elements are then explored to identify distinct types at three levels: wide area inter-settlement routes, local area routes and local area route aggregates. The result is a consistent and coherent set of type families defined by their mereotopological attributes. The attributes in turn provide the basis for ordering the types and establishing the connection between network configurations and urban tissue. The types are applied in an analysis of the town of Leighton-Linslade to demonstrate the resulting differentiation of the street network and the relation between the route type and urban tissue. The paper concludes by assessing the potential for application of the types as well as further research.