Quake rules need review

Construction News

Many other provinces feature soft soil

The regulations issued in 2007 also should cover more provinces and types of construction projects, said Assoc Prof Dr Amorn Pimanmas, chairman of the project committee at the Engineering Institute of Thailand (EIT).

Five provinces are covered by the current ministerial regulations but 14 provinces sit on soft soil that poses risks for collapse of the property if a strong earthquake occurs, he said.

The regulations require tougher seismic design in buildings with a minimum height of 23 metres and total area of 10,000 square metres in Bangkok, Nonthaburi, Pathum Thani, Samut Prakan and Samut Sakhon.

“In fact, provinces such as Ayutthaya and Chachoengsao also sit on soft soil and there are industrial factories in these areas that may report serious damage if they are rocked by strong earthquakes,” said Dr Amorn, who also works at the Sirindhorn International Institute of Thammasat University.

The ministerial regulation focuses on buildings while public infrastructure such as bridges, elevated roads and expressways are not covered.

“The existing law should be amended to cover more provinces as well as other commercial properties such as boilers, cooling towers and piping systems, all of which could be dangerous if quakes cause cracks and leaks of chemical substances,” said Dr Amorn.

Japan, which sits on major faultlines like New Zealand, Taiwan, and the Philippines, has warning and crisis-response systems that are very well prepared and rehearsed regularly. However, the scale of last month’s 9-magnitude quake and tsunami was extraordinary.

“Thailand, on the contrary, like Mexico has a weak system but fortunately nature is not so cruel to us,” he said, referring to an 8.1-magnitude quake in Mexico in 1985 that caused 10,000 deaths in collapsed buildings.

The recent 6.8 magnitude earthquake centred not far from Chiang Rai in Burma shook Bangkok’s high-rises even though the epicentre was 770 kilometres away. However, Dr Amorn said there were faultlines in Kanchanaburi which are linked to the Sakang faultline in Burma, which has the potential to cause a major quake of 8 magnitude.

“Those faultlines in Kanchanaburi are only 350 to 400 kilometres away from Bangkok and they are in danger if quakes happen,” he said.

According to Dr Amorn, almost 10,000 buildings built before 2007 could be considered risky with uncertainty that their structures could withstand a strong quake.

The Bangkok Metropolitan Administration has been urged to regularly inspect bridges and important buildings such as hospitals and government offices to check whether they can withstand a strong quake, he added.

Source: http://www.bangkokpost.com/business/economics/232019/quake-rules-need-review