ENGINEERS AT BRE's Cardington research laboratory last week simulated the effects of a lorry knocking out a load bearing column at the corner of a seven-storey concrete framed building.
The test, funded by the Department of the Environment, Transport and the Regions, involved cutting out a section of a 400mm by 250mm high strength concrete corner column of BRE's European Concrete Building.
Steel support rigs mounted on hydraulic jacks were bolted to the column to take vertical loads.
Gradually reducing the pressure in the jacks to zero simulated the effects of column removal, while more than 200 sensors monitored the effects on the building.
With the corner of the building completely unsupported, the initial downward deflection was only 35mm, demonstrating the development of alternative load paths in the structure.
Only minor cracking was observed by the BRE team.
'It shows just how robust this form of construction is, and will give us a much better understanding of whole building behaviour of real structures, ' said Stuart Matthews, BRE centre for concrete construction director.
'We will also be able to calibrate our finite element modelling tools and demonstrate new monitoring technologies.'