System dynamics: A new approach for the evaluation of urban underground resource integrated development

Abstract The current scale and intensity of urban underground resources (UUR) are greater than ever, and the integrated development of UUR is of considerable significance for urban sustainable development. However, insights on the characteristics of UUR interactions are limited, and thus a quantitative evaluation method is lacking. In this study, we determined UUR interactions to have the following characteristics: spatiotemporal dynamics; multiple influencing factors; chain reactions and synergetic and conflicting coexistence. Based on these characteristics, the system dynamics (SD) method was presented as a new approach to evaluate UUR interactions. Compared with existing methods, SD is not only highly consistent with the interaction characteristics of UUR, but can also quantitatively analyze UUR. Furthermore, by taking the integrated development of geomaterial and urban underground space as a case study, the integrated development impacts were quantitatively evaluated via an integrated two-stage dynamic SD model through Vensim®. The simulation results demonstrate that the GM production of the newly built Beijing subway (991 km, 531 stations) during 2018–2023 can be reduced from 2.07 × 107m3 to 1.33 × 107m3 by integrated development. Moreover, the integrated development achieved favourable environmental impacts, including reductions in the energy consumption from 4.07 × 107kgce to 2.62 × 107 kgce; greenhouse gas emissions from 3.59 × 107kg to 2.31 × 107kg; and landfill space occupation from 9.24 × 106 m3 to 5.95 × 106 m3. This study provides an SD tool for planners interested in the integrated development of UUR and acts as a reference for the assessment of the integrated development impacts.