Safer buildings in the works



WE may not be in the Pacific Ring of Fire, but let’s face it – Malaysians are not immune to earthquakes.

Last month, a 5.6-magnitude earthquake struck near Medan, Indonesia. But its ripples reached Peninsular Malaysia where tremors were felt by residents in Penang and other areas.

In a more devastating event, a quake measuring 6.0 in magnitude rocked Ranau in Sabah, leading to the deaths of 18 people on June 5, 2015.

A year later in August, a three-second tremor sent residents, climbers and hotel guests scrambling when a 4.0-magnitude earthquake hit the area around Mount Kinabalu.

No major earthquakes have struck the peninsula so far but this doesn’t mean it is spared.

Few will remember but in 2009, eight minor quakes were recorded in Bukit Tinggi, Pahang.

More vividly perhaps, those here may recall the tremors felt from the catastrophic 2004 Indian Ocean earthquake near Sumatra, Indonesia, which brought upon the tsunami.

Some Klang Valley folks literally felt the earth moved under their feet while others watched in disbelief as frames on walls swayed on their own.

Our authorities are leaving little to chance now.

New buildings will soon be able to better resist earthquakes and tremors with a design code for buildings currently being drafted to raise safety standards of structures.

The code is expected to be ready by October this year, reveals the Department of Standards Malaysia (JSM), which comes under the Science, Technology and Innovation Ministry.

“It will be applicable to all buildings including houses, commercial areas, landed properties and high-rise buildings.

“But for now, the finer details of the code are currently being deliberated by a working group,” the JSM tells Sunday Star.

Such efforts are a timely development as more Malaysians are moving into condominiums and apartments, with about 30% of the urban population currently living in such high-rise buildings.

But while the code is a welcomed move to ensure the safety of the people, there is one downside – it could lead to more expensive properties.

“When the code is published, it isn’t mandatory for all buildings to follow as it is up to the local authorities to impose such standards.

“But there is likely to be additional costs to make buildings more earthquake-resistant in line with the code.

“This could possibly raise construction costs by about 5% to 10%,” the JSM estimates.

Among the features that can be incorporated to buildings to help it weather quakes are the use of reinforced concrete and seismic rubber bearings.

The group drafting the code comprises officials from relevant government agencies such as Malaysian Meteorological Department (MetMalaysia), Minerals and Geoscience Department, Public Works Department (JKR), Sabah Housing and Real Estate Developers Association, Institution of Engineers Malaysia (IEM), Association of Consulting Engineers Malaysia and other seismic experts.

One of the key points that needs to be ironed out is the Peak Ground Acceleration (PGA) value, which will ultimately determine how much ground movement a building can withstand in the event of a quake.

However, the JSM says determining the PGA value is quite a challenge as Malaysia lacks data on earthquakes, unlike its neighbours which have a longer history of such phenomena like the Philippines.

“With such limitations, it is tough for experts to come up with the value,” explains the JSM.

Calling the quake in Ranau “a wake-up call for everybody,” Science, Technology and Innovation Minister Datuk Seri Madius Tangau says he hopes to introduce the building code as soon as possible.

“Once we have an agreement among the experts, we can finalise the code. The code will have to be approved by the ministry first, just like all standards introduced in Malaysia.

“The only way consumers can feel safe is for us to have such standards.

“We have a job to do and we cannot compromise on safety,” he assures, adding that MetMalaysia is closely monitoring the country’s seismic activities.

Efforts to come up with the earthquake design code was reported by StarMetro in 2015, whereby the IEM had said the Eurocode 8 (EC8) is to be incorporated into Malaysian standards.

IEM president Tan Yean Chin says the design code is not to make buildings earthquake-proof as it would be very costly, but rather to increase resistance against tremors if it happens in future.

“Having earthquake-proof buildings is also unnecessary for a low seismic risk country like Malaysia,” he says.

He explains that IEM and others in the working group, are coming up with a Malaysian National Annex to support the EC8, with design recommendations especially for new building structures, which will suit a low seismic risk zone like Malaysia.

“When the code is approved, each state has its own jurisdiction to determine when to adopt it. Once it is adopted, then all new buildings will have to follow the code.

“As for existing buildings, it will be up to the owners’ discretion to seek advice from professional engineers to assess whether such structures need to be upgraded or retrofitted to comply with the code,” Tan explains.

Fortunately, he assures that owners of present buildings shouldn’t be overly concerned.

“To date, buildings in Malaysia, particularly in the peninsula and Sarawak are considered safe based on records over the past 100 years or more in terms of earthquakes,” he says.

Despite some high-rise structures in the Klang Valley experiencing “swaying” from the 9.1-magnitude Indian Ocean earthquake in 2004, no structural damages were reported.

“This means that existing buildings are still safe after the incident. Therefore, adopting the new code is just like an added measure to improve safety,” Tan says.

He says nobody can predict where and when the next earthquake will strike, even in a low seismic risk country like Malaysia.

Tan explains that tall buildings are more vulnerable to distant earthquakes because high rise structures have lower frequencies in vibration, resonating with the low frequency of seismic waves from distant earthquakes.

“As such, high rise buildings (exceeding 30m) in western Peninsular may be affected by tremors from distant earthquakes such as from Sumatra.

“On the other hand, such tall buildings can better withstand close-range earthquakes compared to shorter buildings.

“This is because the high frequency of vibration from the nearby quake will resonate closer with shorter buildings, causing more damage,” he says.

Concurring with Tan, JKR civil and structural engineering branch senior director Kamaluddin Abdul Rashid says past records show that magnitudes of local earthquakes in Peninsular Malaysia are relatively low.

“If this continues, buildings designed in accordance with the existing Uniform Building By-laws 1984 are considered safe.

“It has been generally accepted by local structural engineers that the impact of seismic tremors from earthquakes in neighbouring regions on Malaysian buildings is not likely to be catastrophic,” he says.

But in Sabah, Kamaluddin says, the local authorities are more cautious and have decided to include the requirements for seismic loads as a criteria before issuing planning permissions.

However, the issue of public safety in the event of earthquake is not confined to providing good building design alone.

“As building owners, we need to ensure that our buildings are well maintained and in good condition.

“A study by JKR found that the risk of building failure in an earthquake is significantly higher for ill-maintained buildings compared to well-maintained buildings that have not been designed according to seismic standards.

“Thus, it is money well spent to maintain buildings because they will better withstand earthquakes,” Kamaluddin adds.

Related stories:

We don’t mind a hike but keep it reasonable, say consumers

JSM: Better design standards to make buildings quake resilient


   

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