Effect of visibility on multilevel movement: a study of the high-density compact built environment in Hong Kong

Hong Kong's built environment is characterized by compact urban form with vertical distribution of land uses. The large mixed-use urban complexes, accessed through multilevel spatial structure, have various types of movement spaces like square, atrium, podium, footbridges, etc. This variety of spatial expression induces a varied pattern of movement that in turn has implications for the extreme high-density urban living. Using visibility graph analysis, this study investigates the effect of visual dimensions on the patterns of multilevel pedestrian movement. Owing to the prominence of local urban design parameters such as the mass transit railway, level variation, and vertical transitional spaces, this study develops an integrated model that includes the visibility variables and variables to take into account the effects of these key urban design parameters in a single statistical model. Findings of the study reveal that the visibility properties seem to have significant effects on the patterns of multilevel movement. The study outcome suggests that notwithstanding the strong influence of the local urban design parameters, the visual dimension of the multilevel space system may prove to be an important parameter for the description of pedestrian movement in other highly complex but comparable built environments. URBAN DESIGN Intenrnational (2008) 13,169-181. doi:10.1057/udi.2008.22