Digital twins (DTs) offer promising benefits to address several inherent problems in underground construction, yet confusion surrounds the concept due to its context-specific nature which hinders more widespread adoption. This paper seeks to clarify DT-related terminologies from a built environment perspective and define the features and maturity levels of DTs for underground spaces, considering their unique challenges. A layered architecture for constructing DTs is proposed, offering various options based on functionality, technological advancement, and expected value. Additionally, a comprehensive literature review of technologies enabling the development of digital twins for underground spaces is presented, including data-driven ground modelling, site investigation and design process integration with BIM, computational BIM, and advanced sensing and instrumentation. The paper identifies synergies between DTs and the observational method in geotechnical engineering, highlights research gaps, and proposes a transition to a prescriptive, knowledge-based DT. Furthermore, exemplar use cases of underground DTs throughout their lifecycle are explored, demonstrating their potential value.

中文翻译：

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城市地下空间的数字孪生


数字孪生 （DT） 为解决地下施工中的几个固有问题提供了有希望的好处，但由于其特定于环境的性质，阻碍了更广泛的采用，因此围绕该概念存在混淆。本文试图从建筑环境的角度阐明与 DT 相关的术语，并考虑到其独特的挑战，定义地下空间 DT 的特点和成熟度。提出了一种用于构建 DT 的分层架构，根据功能、技术进步和预期价值提供各种选择。此外，还对能够为地下空间开发数字孪生的技术进行了全面的文献综述，包括数据驱动的地面建模、现场调查和与 BIM 的设计过程集成、计算 BIM 以及先进的传感和仪器。本文确定了岩土工程中 DT 与观测方法之间的协同作用，强调了研究差距，并提出了向规范性、基于知识的 DT 的过渡。此外，还探讨了地下 DT 在其整个生命周期中的示例用例，展示了它们的潜在价值。