Suitability Evaluation of Underground Space Development by Considering Socio-Economic Factors—An Empirical Study from Longgang Region of China

Underground space is considered a critical urban resource that can significantly promote sustainable development under rational planning. This study, taking the Longgang region in SE China as an example, comprehensively considers the dual influences of geological environmental factors and socio-economic factors, incorporating socio-economic factors as key cost indicators. Following the principle of “stratification and classification”, a detailed assessment framework was developed to evaluate the suitability of underground space for development across various depths, and a systematic analysis of development suitability was conducted. Specifically, we employed a fuzzy comprehensive evaluation method to assess the suitability of underground space. During this process, an analytic hierarchy process (AHP) was used to determine the weights of geological environmental indicators, and the group judgment matrix approach was applied to assign weights to the socio-economic factors. The results indicated that, for shallow spaces, areas with high resource potential accounted for approximately 10.0% of the region, while areas with relatively high resource potential accounted for 28.5%. For medium-depth spaces, areas with high resource potential comprised 19.9% of the region, and areas with relatively high resource potential accounted for about 35.1%. These findings suggest that the study area demonstrated promising prospects for the development and utilization of underground space. The proposed approaches ensured that the evaluation results were both scientific and reasonable. By integrating the impact of socio-economic factors into suitability evaluation, the outputs provided more scientifically grounded guidance for urban planning.