Progressive collapse: Past, present, future and beyond

The world has seen a surge in rigorous study efforts on the progressive collapse of structures in the past few decades. These events have led to new standards and provisions in building codes of practice, many of which are still being developed and updated today. Although there have been some excellent reviews covering different aspects of progressive collapse, the sheer volume of research performed in this area in recent years means that highly relevant investigation methods and research findings are not covered by them. To fill this void, this review article aims to provide an up-to-date and comprehensive overview of progressive collapse research on building structures. The review is organised into eight sections that cover: (1) essential background information; (2) prominent collapse cases; (3) progressive collapse typology; (4) design standards; (5) investigation methods; (6) prevention and mitigation strategies; (7) structural types and characteristics that require special consideration; and (8) future research needs. In addition to the fundamental concepts, this review encompasses recent advances, such as employing physics and game engines, and machine learning to study progressive collapse. It also explores the potential future applications of these new concepts in research. Furthermore, the review emphasises recent progress in improving the robustness of timber and modular structures. Therefore, this review provides a crucial resource to acquire a global overview of current state-of-the-art progressive collapse research and future requirements, making it valuable to both novice and experienced practitioners and researchers.