Previous research into the mitigation of vibrations in structures has mainly revolved around earthquake and wind induced vibrations (Nyawako, Reynolds, 2007). Human induced vibrations into modern structures is becoming an ever more important aspect in advanced building design. The advances in materials, computer modeling, and computer aided design is allowing for the design and construction of increasingly efficient and lightweight structures. This in combination with the modern architects vision for open plan concepts are making vibration control ever more difficult (Smith, et. al., 2007). As a result we are seeing increased spans, and decreased overall structural depth of floor systems to increase the useable space in buildings, which is driven by an increased aesthetic appeal. A good example are the ever more slender bridge decks being constructed today. This design philosophy is now yielding lower mass structures with lower stiffness, and hence lower modal frequencies that can be easily excited by low mass sources such as human movement or activity (Nyawako, Reynolds, 2007).
The rhythmical movements of everyday human activity can pose discomfort to the building inhabitant or users in these lightweight structures. It is estimated that 20 seconds or more of rhythmic body motion will lead to almost periodic dynamic forces. Typically human induced vibrations cause only a serviceability concern to structures, however in rare cases upgrades have been made to structures to avoid fatigue induced failure (Nyawako, Reynolds, 2007). It should be noted however that this human induced serviceability problem can also lead to loss of life even when fatigue failure is not considered. Excitation in a full concert hall or s...
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.... 39, No. 6, November 2007, Pages 465-493.
Smith, A. L., Hicks, S. J., Devine, P. J., SCI P354 Design of Floors for Vibration: A New Approach, The Steel Construction Institute, Silwood Park, Ascot, Berkshire, UK, 2007.
Stoyanoff, S., Hunter, M., Footbridges: Pedestrian Induced Vibrations, RWDI Tech Notes Issue No. 15, January 2006, Available Online: http://www.rwdi.com/cms/publications/34/t 15.pdf
Thambiratnam, D. P., Perera, N. J., Abeysinghe, C. M., Hunang, M., Human Activity-Induced Vibrations in Slender Structural Systems, Structural Engineering International 2/2012, Scientific Paper, Pages 238-245.
Unknown Author, Planning for Footfall Vibration in Steel-Framed Floors, RWDI Tech Notes Issue No. 35, November 2009, Available Online: http://www.rwdi.com/cms/publications /91/RWDI_Technote_-_Planning_for_footfall_vibration_on_steel-framed_floors_ print .pdf
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