Future EU skyscrapers to be built on anti-terror guidelines

Date: 10/01/02

By Peter Chapman

EUROPEAN standards experts are set to approve a design blueprint that would reduce the risk of new EU-built skyscrapers collapsing if they ever faced a World Trade Center-style terrorist attack.

The Brussels-based European Standardization Committee (CEN) has produced 58 design guidelines, known as 'eurocodes', for architects. The idea is to give office workers and apartment-block residents a better chance of survival if the worst was to happen.

Professor Haig Gulvanessian, head of the relevant CEN group, said the national standards bodies forming CEN's membership had already rubber-stamped a key section of the guidelines. These cover basic requirements such as buildings being designed to avoid being 'damaged by events such as explosions, impact and the consequences of human error' to an extent 'disproportionate to the original cause'.

Commission industry chief Erkki Liikanen - responsible for EU standards policy - said the Commission had supported the eurocodes since work began on their development back in 1975.

But he said there were no plans to make the standards - which cover mainly civil-safety issues such as the impact of earthquake, storm or floods on buildings and bridges - mandatory for member states. That is because they, not the EU, have the final say over construction laws.

Gulvanessian said it would be up to national regulators and clients commissioning buildings to interpret the extent to which they would apply, adding that the new standards, coupled with good engineering practice, could produce virtually indestructible buildings.

'But if you are going to design everything for a plane to hit it you would never build anything. It would be too expensive,' he admitted.

Instead, he said the key issue was the level of protection clients and regulators decided they wanted to guarantee - adding there could be little scope for guarding against 'guided missiles or nuclear attack'.

This meant regulators or clients could insist on reinforced floors at regular intervals so that a building would not fall, or say they wanted two hours to get out in the event of a fire.

'You cannot guarantee 24-hour fire resistance. But two or three hours is reasonable,' said Gulvanessian, who believes the catastrophic events on 11 September could have been mitigated had similar standards been used when the twin towers were erected.

'What you can argue is that if that building had not collapsed and that people had just died in the four or five floors where the planes hit, then it was not disproportionate. But the fact that it collapsed was disproportionate.'

French engineers have used eurocodes plus design data from the twin towers and the two crashing jets to model the time it took for the structure to collapse.

The towers were built with structural supports in a central core containing lift shafts, stairs and ventilation as well as in the façade.

Liikanen said there are no known examples of similar designs in high-rise EU cities, although he admitted 'very few civil engineering works are designed to resist an impact like the one suffered on 11 September'.

European standards experts are set to approve a design blueprint that would reduce the risk of new EU-built skyscrapers collapsing if they ever faced a World Trade Center-style terrorist attack. The European Standardization Committee (CEN) has produced 58 design guidelines known as 'eurocodes' for architects.

http://www.cen.eu/ http://www.cen.eu/

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