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.

A structure in its permanent state cannot be ‘wished into place’. Appropriate consideration must be given to construction methodology so that permanent works can be optimised, temporary works minimised and trade interfaces simplified. This article presents a list of general, high-level considerations that relate to construction methodology and optimisation of temporary/permanent works, with a number of examples provided.

The permanent works designer (PWD) has a major influence on the temporary works and can, for example: eliminate temporary works, e.g. through the use of steel decking rather than timber falsework minimise the use of temporary works, e.g. by using the permanent capping beam as a waling in basement construction design the permanent works so that simple temporary works solutions can be used.