Arnold C. Y. Yong is a senior civil engineer at Sepakat Setia Perunding (SSP) in Malaysia. He earned his PhD degree at the University of Melbourne where he continued his research as a post-doctoral fellow. During his time at the university, his research primarily focused on collision actions on structures. He led a number of experimental programs involving large-scale dynamic testing funded by the Australian Research Council (ARC), and has provided expert advice to the Geotechnical Engineering Office (GEO) of the Government of the Hong Kong Special Administrative Region to assist developing design guides for protection against landslides and rockfalls on hillslopes in built-up areas. Nelson T. K. Lam is a professor and leader of the Structures and Buildings Discipline in the Department of Infrastructure Engineering at the University of Melbourne. He is editor of the Australian Journal of Structural Engineering, member of the Structural College Board of Engineers Australia and a member of the committee responsible for the Australian standard for seismic actions. Nelson has earned many awards for his research, including the Chapman Medal (1999, 2010, 2019) and Warren Medal (2006) from Engineers Australia. Scott J. Menegon is a consulting structural engineer and academic with expertise in reinforced concrete, earthquake engineering and collisions actions. Scott earned his PhD from the Swinburne University of Technology, where he was the joint inaugural recipient of the prestigious Dr William Piper Brown AM scholarship. Scott currently works in industry and maintains his affiliation with Swinburne as an Adjunct Industry Fellow. His achievement in research was recently recognised by the award of the Chapman Medal (2019) by Engineers Australia.