Call for new seismic code for high-rise towers

A leading structural engineer in Dubai believes it is time the UAE updated the safety regulations governing the seismic design of buildings following the earthquake tremors felt in the country.

But Alaa Sahawneh, design director for Dubai Civil Engineering, said on Thursday there was a low risk of major structural damage or collapse of tall buildings caused by earthquakes in the UAE.

On Wednesday thousands of people were evacuated from Sheikh Zayed Road in Dubai after tremors from a 6.2 earthquake in southern Iran were felt across the UAE.

According to the UAE Ministry of Public Work, tall buildings of five storeys in height or more, together with buildings considered important by the authorities such as hospitals, fire and police stations, electrical stations and government buildings must comply with the Zone 2A classification of the Uniform Building Code (UBC).

Under this regulation, a structure should be able to resist an earthquake measuring 5.5 on the Richter scale.

Sahawneh said the UAE still adopted the UBC code, despite it dating from 1997 and having since being replaced in the US where it was devised and elsewhere by the more up-to-date International Building Code (IBC).

“We think that using a better code or newer code will reduce the risk,” he said.

“We are trying to promote the possibility to update the code here as we believe the newer code is more updated and more accurate.

“But I don’t think there’s a high risk to the buildings here, especially new buildings.

“In case of a serious earthquake if it exceeds the moderate zone of 5.5 on the Richter scale there will be damage to the building such as the façade like glass but not structural damage and total collapse.

“The UAE area is a seismic stable zone and is a low risk but Dubai Municipality asks for buildings to be built to a moderate standard with Zone 2A.”

He said buildings over 300 metres in height were more at risk from strong winds than from earthquake damage.

“In higher towers like the Burj Dubai the seismic force will not be the governing force it will be the high wind so they are designed to resist high wind rather than earthquakes, “said Sahawneh, whose firm is working on the construction of the 300 metre Torch Tower in Dubai Marina.

Dubai Municipality said last year it was in the process of preparing a new set of seismic codes for Dubai based on data taken from four seismic monitoring stations located around the UAE. No one was available to comment from Dubai Municipality on Thursday.