The University of Sheffield
Department of Civil and Structural Engineering

Ruirui Sun - Research Student

Telephone: 25726
Room: D120

email : Cip07rs@sheffield.ac.uk

Research Group

Research Project

Mechanisms of Progressive Collapse of Buildings Attacked by Fire and Explosion

Since the collapse of the World Trade Center twin towers on 11 September 2001 structural engineers and researchers face the challenge of preventing progressive collapse of tall buildings attacked by fire or explosion. It is important to understand how buildings perform in such events. The behaviour of buildings in fire or explosion is complex and full-scale tests are expensive. Thus the role of modelling to predict the sequence of behaviour of structures in fire or explosion will become increasingly important. If confidence can be generated in the techniques used, structural response to such accident scenarios could be investigated cheaply and improve the safe structural design of composite steel-framed buildings. The software Vulcan has been developed by Structural Fire Engineering Research Group at Sheffield for three-dimensional analysis of the structural behaviour of such buildings in fire, subject to quasi-static loading. The main objective of this research is to develop the software to full progressive collapse capability, by:

  1. Introducing explicit dynamics into Vulcan so that it can be used to model transient behaviour under explosive and impact loads, in addition to its present capability for large-deflection behaviour under elevated temperatures. This will allow all these effects to be modelled simultaneously, and will make the program a very powerful tool for modelling structural behaviour of buildings subject to earthquake, impact or explosion followed by fire.
  2. Performing intensive parametric studies, to increase the depth of understanding of the progressive collapse of buildings in such accidents. The main areas to be investigated initially are the rearrangement of internal load-paths due to the failure of key structural members; the significance of connection behaviour and the influence of different bracing systems.
  3. Producing guidance for designers which will improve the inherent robustness of buildings, in order to prevent collapse in extreme events, in cases where risk levels justify non-standard design concepts, which will also help to underpin the scientific basis of structural design decisions.