An approach to built-form connectivity at an urban scale: system description and its representation

This paper, the first of a sequence, defines built forms as quasi-mathematical models and uses graph-theoretic representation in order to express how buildings are connected and packed over an area of land. Buildings are represented by points called built forms; external walls and partitions (party walls between buildings) by lines. The connected subgraphs made up of built forms and partitions are called arrays of built forms. This constitutes a simplified view of the built-form subsystem which, together with the channel network, gives rise to an urban graph.Twelve measures representing either the connectivity amongst the elements of the built-form subsystem or of the adjacency between built forms and the external environment are defined in order to provide a numerical scale for the properties under study. The majority of these are ratio measures which will be evaluated in a subsequent paper by use of actual data.