HORIZONTAL MOTION readings taken during Monday morning's West Midlands earthquake are unlikely to affect the debate over seismic design codes, experts told NCE this week.
The quake was one of the largest felt in the UK for decades and measured 4.8 on the Richter scale. Houses and buildings were shaken over a wide area around its Dudley epicentre.
But horizontal accelerations measured by 'strong motion instruments', the nearest of which was 80km away in central Wales, were less than half the advisory threshold recommended in Eurocode 8, which is due to come into force in the UK within two years.
Seismic engineer and UK Eurocode 8 national technical contact Edmund Booth said that the government was still awaiting recommendations from the British Standards Institution on the benefits of applying recommended threshold values in the UK.
'This would affect just over a third of the UK, ' he said. 'But the government has the power to raise this threshold and effectively exclude the UK from Eurocode 8 completely.'
British Geological Survey seismologist Chris Browitt explained that there were only a dozen or so strong motion instruments scattered across the UK.
'Every earthquake adds to the database, but the data from this particular event isn't going to help resolve the debate over Eurocode 8 very much, ' he added.
Booth is seeking the views of UK engineers on whether or not the UK should adopt Eurocode 8.
He pointed out that even if it was adopted at existing threshold values, simplified design methods would be acceptable and no seismic detailing be required.