Urban underground space (UUS) has been playing an important role in the urban development in recent years. The evaluation for its potential becomes essential for urban spatial planning. Previous research emphasized the fundamental data, while this paper not only emphasized the data provided by related departments, but also took into consideration the gap and relation between UUS and urban spatial planning. To provide theoretical support for urban spatial planning, this paper studied a method for evaluating UUS. In this method, an index system for UUS resource evaluation was put forward and its analytical process was based on the Geographic Information System (GIS) and some mathematical tools, such as the analytic hierarchy process (AHP), the most unfavorable grading method (MUGM) and the exclusive method (EM). Then this method was applied to UUS Master Plans and Detailed Regulatory Planning in Chinese cities, and proved to be relatively practicable. The research outcomes are presented in the form of two papers, each with a different focus. Part 1 aims to introduce the evaluation methodology, including construction suitability evaluation & potential value evaluation & volume estimation. Part 2 reports on applications of the method to Chinese cities of Tongren and Changzhou.Part 2 demonstrated the UUS resource evaluation methodology for Tongren city and Changzhou city in China. In Tongren, the UUS construction suitability and resource’s comprehensive quality (RCQ) evaluation was implemented on an urban scale. Firstly, factors influencing the potential for UUS, including the area’s landforms, engineering geology, hydrogeology, site stability, existing subsurface construction conditions, urban location, and land use were collected and analyzed based on GIS. Furthermore, a combination of AHP, MUGM and EM techniques were used in the analysis. Then the UUS construction suitability and RCQ distribution were got. The UUS layout structure was finally obtained based on RCQ distribution figure. Meanwhile, this case study shows that the area used for UUS accounts for only 2% of the effective utilization area of the whole city based on the volume estimation model. While for Changzhou, existing construction evaluation at the parcel scale was implemented for one downtown area. A “four steps” method was proposed to calculate the influence depth of building foundations based on the geographical statistical analysis module of GIS with an interpolation method. Flexible application of the method, with the addition of local project experience, can make the planners definitely determine which part of the area can be exploited. A flow chart of existing construction evaluation is finally presented.
Read full abstract