Ahsan Ali

• Floods are a highly destructive natural hazard that results in severe social and economic impacts. Traditional hazard-based approaches to flood management necessitate urgent improvements. A paradigm shift has been observed toward adopting a flood risk management (FRM) framework. This framework entails a multi-tier risk analysis approach to identify and mitigate flood-related hazards in an integrated manner. By reducing the hazard levels and potential damages, FRM treats these risks at various levels. In FRM, the development of flood-resilient buildings and infrastructures constitutes a crucial measure. However, current building resilience strategies lack the incorporation of distinctive building characteristics and their unique behaviours in risk evaluation. The need for new approaches and technological tools is imperative for the accurate evaluation of flood risk and the development of resilient buildings and infrastructures. The fast-paced changes in today's world require the incorporation of innovative technologies in the FRM domain to achieve flood- resilient buildings. However, the integration of new technologies, especially big data, presents new challenges for FRM. To overcome these challenges, the potential of emerging technologies in the FRM domain was investigated, revealing that their integration could enhance FRM. The integration of Geographic Information Systems (GIS) and Building Information Modelling (BIM) has been identified as a promising approach to improve FRM by merging hydrodynamic flood and building information into a single geospatial environment. This study investigates how the integration of GIS and BIM can improve flood risk management by creating a 3D digital twin for flood-resilient buildings, and to assess its potential for supporting flood impact assessment on buildings. In this multidisciplinary study, a novel, multiphase model workflow has been developed to create a 3D digital twin environment in order to enhance FRM for flood-resilient buildings. The digital twin enables an automatic 3D assessment and calculation of flood-induced impacts on a building and its individual components. To validate the functionality of the developed model workflow, a prototype case was implemented to assess the feasibility of its different phases. The prototype case highlighted limitations in the developed model workflow, and the lessons learned from this exercise were used to improve the methodology. The revised methodology was then tested with real-world data in a subsequent case study, resulting in improved accuracy and effectiveness. Leveraging the 3D digital twin framework, numerous geospatial analyses were partially automated within the digital twin environment to evaluate the impact of flooding on diverse building components. The developed system enables thorough evaluation, computation, and identification of flooded building components, as well as the partially automated calculation of flood-induced actions, pressures, and forces on both structural and non-structural building components. The computed pressures and forces from various flood actions can be transferred to various material and structural analysis software for further analysis of building and component stability. Furthermore, the developed 3D digital twin enables more comprehensive data visualization, enhancing users' ability to perceive the interrelationships between building and flooding information. This facilitates the identification of potential risks and enables more effective communication with stakeholders involved in building design and flood management. By leveraging the same information system, better communication, effective planning, and improved outcomes can be achieved.