Temporary Works Toolkit. Part 19: An introduction to the demolition of large stuctures

Many modern office towers are of steel-composite constructione. However, the lightweight nature of steel means a lower modal mass – and vibrations from active sources (e.g. footfall) need be considered carefully during the design stage. This article discusses vibration performance and mitigation based on recent experience in Singapore.

Last month’s article in the series covered the theory and detailed methods recommended for calculating backpropping loads. This article continues by discussing some of the design issues and preconceptions related to backpropping, and gives worked examples.

Current highway bridge designs in the UK tend to favour either composite steel girders with a precast or in situ concrete deck for long spans, or precast concrete beams with an in situ concrete deck for spans of less than 40m. This article considers temporary works, in particular the use of temporary supports, to precast concrete bridge beams during deck construction.