BarrierDT: A Digital Twin of Rigid Debris-Resisting Barriers for Geohazard Event Monitoring and Risk Assessment

Rigid debris-resisting barriers are one of the most commonly adopted structural countermeasures for landslides and debris flows from natural terrain slope failures on natural hillsides in Hong Kong[1]. As urban development gradually encroaches toward natural hillsides and weather patterns become erratic from climate change effects, the risks associated with landslide debris hazards will undoubtedly increase. It is therefore essential that the barriers are designed, constructed and maintained with an adaptation to changing conditions of geohazard events driven by climate change. One emerging area of research which focuses on addressing this challenge is the creation of `digital twins' for rigid barriers. A digital twin serves as a virtual representation of the physical infrastructure (i.e. the physical twin), which can be updated in near real time as new data is collected, provide feedback into the physical twin and perform `what-if' scenarios for assessing asset risks and predicting asset performance.
This paper presents our exploratory study towards creating a digital twin of rigid barriers for geohazard event monitoring and risk assessment purposes. In particular, it is an interdisciplinary study involving modelling, monitoring and simulation, using rigid barriers in Hong Kong as case studies. Four areas of research were investigated: (i) 3D reconstruction of rigid barriers using UAVs and Structure-from-Motion (SfM) methods, (ii) BIM modelling of rigid barrier with Scan-to-BIM methods and parametric modelling, (iii) near-real-time monitoring of rigid barrier, and (iv) prompt landslide and debris flow event simulation with consideration of risk mitigation effects of rigid barriers in place using fast simulation approaches. The rigid barrier's performance of resisting large dynamic impact loads imposed by landslides and debris flows are simulated and evaluated with the BIM model modelled as-built of real site barrier structure, and real-time monitoring IoT sensor data. A new framework for creating a digital twin of rigid barriers for event monitoring and risk assessment, is proposed and briefly discussed. Since impacts of debris-resisting barriers by landslide debris are rare events in Hong Kong, this study also sets out a new outlook on assisting the implementation of the performance-based approach in the design of rigid debris-resisting barriers.

Keywords: Rigid barrier, Digital twin, Scan-to-BIM, Parametric modelling, Fast simulation.