Goodbye BS 8110 and BS 5950. Hello EC2 and EC3. New structural Eurocodes will be in use in the UK by March next year and all national standards that conflict will be withdrawn by March 2010. But are consultants doing enough to make sure they're ready for the changeover?
Eurocodes have been a long time coming since the first discussions on a single European code kicked off in 1975. But they are now literally on our doorstep.
Austria and Denmark fully adopt structural Eurocodes next year, and in the UK major public authorities like the Highways Agency will start to accept Eurocode designs by next year (see News).
All 10 structural Eurocodes – EN 1990 to 1999 – with the exception of the towers and mast section of the steel code, have now been published and the time for liking or disliking Eurocodes is past. They are here to stay and we need to embrace them in the same
way that we changed from imperial to metric.
However, it's not all doom and gloom. The new Eurocodes are claimed to be the most technically advanced codes in the world. Eurocode rules have been developed in many cases from non-linear studies and the advanced analysis techniques should result in more economic structures.
For example, according to Atkins head of bridge design and technology Chris Hendy, speaking at last week's NCE conference on Eurocodes, a 55% reinforcement saving was made on piers for the Channel Tunnel Rail Link's Medway Bridge using a non-linear analysis in accordance with the draft EC2, compared to using BS5400 part 4.
The design of slender piers is a special case as BS 5400 is quite conservative. However, it is expected that there will be material cost savings up to 5% when designing in concrete to the new Eurocodes.
From the cost perspective, there will undoubtedly be more pressure from design and build contractors to adopt Eurocodes. A leaner structure has the added benefit of being more sustainable and should be finding favour with the green lobby. Either way, by adopting Eurocodes early, a competitive edge can be achieved.
Eurocodes are making headway in engineering design, enabling leaner design and providing a common ground for engineers in Europe and beyond. The reality is that engineers need to grab the opportunity with both hands or face being left behind.
The potential business opportunity is huge. Anecdotal evidence even suggests that engineers in other non-European countries such as Malaysia and South Africa are already gearing up for the switch in the knowledge that the introduction of Eurocodes and the effective levelling of the playing field will see the consultancy marketplace open up internationally.
But Eurocodes will, of course, also provide more opportunity for UK designers to work throughout Europe.
Yet while, in the short term, the transition will indeed cost money and bring disruption, it may not be as bad as people think. After all, the industry survived the change from service state to limit state design.
And besides, some of the money involved in retraining staff for the changeover would be spent as part of the training budget anyway. By making use of in-house experts, costs can be reduced further and by making use of a subscription-based online standards provider, which many consultants subscribe to as a matter of course, the extra materials required such as handbooks and codes have already been paid for.
The 10 structural Eurocodes are named EC0-9 (EN1990 – 1999 to be formal) and are listed in an order that relates to the original but long superseded publishing plan. The 10 are broken down into a further 58 parts.
EC0 (EN1990) is a key Eurocode that forms the basis of structural design and deals with issues such as structural safety, serviceability, robustness, fire, durability and design working life. EN 1(1991) covers action on structures like imposed, snow and wind loads.
EC2-9 (EN1992-1999) covers the design and detailing for different materials as well as geotechnical and seismic design.
Each of the 58 Eurocode parts has a corresponding national annex that contains country specific values. So far, just 14 national annexes have been published, with the remaining annexes in the pipeline.
However, all bridge-related national annexes are expected to be published by March next year, triggering the start of the Highways Agency's use of Eurocodes.
And once the national annex for the wind code is published at the end of July next year, we should also start to see more buildings being fully designed to Eurocodes.
All of the remaining national annexes will be in place by the end of December 2008.
At this point, there will be a period of coexistence where Eurocodes and British Standards sit side by side. However, by the end of March 2010 the British Standards will all have been withdrawn – and once withdrawn, the whole of the standard has to be taken out of use.
But some of the withdrawn information is not covered by Eurocodes – this information will be reissued to assist designers as non-contradictory complementary information (NCCI). Extra guidance will also be available from BSI.
The period of coexistence is likely to be a very useful time for the industry to get to grips with the new system. It will see a period of re-adjustment where materials, software and manuals can be resourced, tried out and tested.
And while designs to the old British Standards will still be accepted after 2010 by checking authorities, engineers should check their contracts to see whether they are contractually obliged to design to the new codes.
And the message is clear: don't wait too long to get up to speed on Eurocodes. It could start to impact your business sooner than you think.