Post-occupancy evaluation of the urban underground complex: A case study of Chengdu Tianfu Square in China

The urban underground complex (UUC) is an important approach in the utilization of urban underground spaces in high-density Asian cities. Presently, UUCs in China are large in scale and in quantity, which makes it necessary to assess the condition of UUCs and evaluate whether they meet users' requirements. This can serve as feedback and optimize the design and construction of UUCs. This research employs post-occupancy evaluations (POEs) to determine the major problems and concerns among UUC users and assess their satisfaction levels, taking the Chengdu Tianfu Square UUC as an example. Field interviews and online and field questionnaire surveys were used to establish an index set. The results revealed that transport convenience and transfer efficiency were the most frequently mentioned issues by users. They were less satisfied with the UUC's walking accessibility, internal physical environment, and orientation. The spatial morphology and texture, space proportions, color, decoration, materials, and overall planning had a higher correlation coefficient with the overall user satisfaction results. Eight main factors were identified through factor analysis, which represents the eight key aspects that the design of UUCs should focus on.