Abstract:Urban geological coring drilling serves as a critical method for acquiring subsurface geological information. The complex subsurface geological conditions in Beijing impose higher requirements on core quality， while current drilling operations face challenges such as a lack of standardized procedures and inconsistent core quality. To establish a coring drilling specification system tailored to the urban geological work in the capital， this study reviews the current development status and core challenges of urban geological coring drilling in Beijing. It analyzes the application characteristics and applicable scopes of various techniques， including percussion drilling， conventional rotary drilling， shallow rotary drilling， multi-functional direct-push drilling， and sonic vibration drilling. Based on different scenarios-such as urban land and groundwater environmental investigation， underground space development condition survey， geological hazard investigation， and geo-environmental monitoring-the study defines refined requirements for cores in terms of undisturbed property， cleanliness， representativeness， and information correlation. Furthermore， it proposes core technical solutions including stratified differentiated core recovery rate standards， disturbance and cleanliness level classification systems， a "target-stratum-technique" adaptation matrix， and a full-lifecycle information traceability mechanism， thereby establishing a comprehensive and highly targeted normative framework with strong operability. The research outcomes provide technical support for improving the quality of urban geological coring in Beijing and serve as a reference for other megacities in China undertaking similar work， which are of great significance for consolidating the geological guarantee foundation for urban safe development.
