| Urbanization has led to an increasingly acute conflict between supply and demand for urban construction land. The development and utilization of urban underground space (UUS) have become an extremely significant way to solve city problems, enhence urban resilience and create a low-carbon society. The direct carrier of UUS is the geological environment, coupled with its own three-dimensional (3D) spatial properties, making 3D geological modeling essential for underground space, especially urban underground space planning (UUSP). UUSP is not limited to the 2D level but is a 3D control covering both vertical depth and horizontal extent, aligning with the concept of 3D geology. However, the current application of 3D geological modeling in UUSP remains unclear. In this study, a selected area in Beijing city was chosen as the study area, and a 3D geological model of the shallow underground space was constructed through data collection and data analysis combined with 3D modeling technology, by utilizing 1041 engineering boreholes and 34 cross-sections. The specific application of 3D geological modeling in UUSP was then discussed from three aspects: 3D stratigraphic structures, key geological layers, and the combination with evaluation results. By integrating 3D geological model with geological suitability assessment results, geological support was provided for UUSP in the study area from the perspectives of both vertical depth and horizontal extent, also offering a reference for future regional-level underground space planning in Beijing. |