Prospecting the fine morphological characteristics of urban streets: how constitutedness and permeability can sustain opposite edges case study approach, Baghdad, Iraq

The primary benefit of studying urban morphology is to identify more precise criteria for analysing various street edge levels. A fundamental policy is to characterise urban form through its components, such as plot, block, building, and street pattern. Nonetheless, the arrangement of these components and their interconnections remains a complex and significant issue. This paper primarily aims to perform a micro-scale morphological assessment at the street level. The street features two contrasting edges that create an enclosure for its users. These two edges largely manage and regulate the varying demands and desires of people. This paper discusses the parameters of street edges through two concepts: constitutedness and permeability. The research methodology focuses on the street edge and uses a case study approach to explore a specific neighbourhood. The case study is located within the oldest and most traditional pattern of the urban context of Baghdad city, Iraq, and examines the micro characteristics and parameters of its street edges. The study quantifies and measures a number of variables to determine the potential of the street to formulate the two opposite edges, and its ability to attract people for different reasons. To trace its characteristics, micromorphological techniques of analysing the street edge are applied as key research methods, which include Multiple Centrality Assessment (MCA) and plot(s)-based analysis. The street edge is then examined according to two measures (equations): constitutedness and permeability. The result of applying these equations will be discussed and correlated with constitutedness and permeability and with the value of centrality (MCA). A key contribution to this paper is its emphasis on the quantitative characteristics of the neighbouring street edge, as well as the betweenness centrality. It is a significant approach to address the street-level edge, where most people tend to benefit from the adjacent edge for various demands and purposes.