Evaluation of existing underground public space supply based on the Node-Place-Experience model

Abstract

The development of underground public space is considered to be a major contributor to urban sustainability. However due to the lack of customized tools for identification and assessment the effective or ineffective supply of existing underground public space has yet to receive sufficient attention resulting in frequent problems such as its undersupply and underutilization of space. Therefore this study proposes three assessment frameworks for existing underground public spaces namely traffic supply (Node) land use and activity diversity (Place) and user experience (Experience) to judge the effectiveness of the supply in 13 cases in the main urban area of Chongqing by the degree of balance of the three dimensions, and to categorize the results of the evaluation through hierarchical clustering. The study confirms that except for Nanping the other cases suffer from under-provision especially in terms of transport provision such as the low connectivity of the existing underground public space to other urban spaces. Afterward we classified the evaluated cases into four clusters: “unsustainable place with potential to be balanced,” “developing balanced with promising potential to be balanced,” “developing balanced with potential to be balanced,” “developing balanced with lower potential to be balanced” and proposed corresponding optimization paths. Our method can be used as an effective tool to identify and measure the effectiveness of existing underground public space supply and to provide a database and decision support for the optimization of future renovation of the project.