Office footfall vibrations: a discussion on response factor for design and mitigation measures

Steel is an excellent construction material with a high strength-to-weight ratio. As such, it is gaining popularity in metropolitan Asian cities such as Singapore. Many modern office towers are of steel-composite construction – which is lightweight and achieves faster construction cycles compared to concrete construction. Savings on foundation costs may also be significant, especially for tall buildings, due to the lighter weight of steel compared to concrete. However, the lightweight nature of steel will also mean a lower modal mass generally; therefore, vibrations from active sources (e.g. footfall) will to need be considered carefully during the design stage. This article discusses vibration performance and mitigation based on recent experience in Singapore.