Stocahstic Approach to Human Structure Dynamic Interaction

Human-structure dynamic interaction is defined not only as the influence of humans on the dynamic properties of structures they occupy, but also as forces which excite these structures. Both of these issues are becoming increasingly important for all slender civil engineering structures occupied and dynamically excited by humans, such as footbridges, long-span floors, grandstands and staircases. The problems are typically caused by excessive vibrations of such structures due to normal activities of their human occupants, such as walking, running and jumping. The excessive lateral vibrations of the infamous Millennium Bridge in London is the best known example of this problem. The human involvement in the problem the key source of considerable randomness in the following three key types of human-structure dynamic interaction: (1) human-induced dynamic actions on structures,(2) changes of structural dynamic properties due to the presence of humans, and (3) perceptions of structural vibration responses. Although the concept that we are all different is quite understandable, there has been almost no effort to articulate it within a common probability based theoretical, analysis and design framework of the kind which exists for other random excitations of civil engineering structures such as wind and earthquakes. The provision of this framework would enhance tremendously understanding of human-structure dynamic interaction and enable easier application of its various aspects in practice, including a development of more reliable design codes in civil structural engineering. The development of this novel framework is the key aim of this Fellowship.