Thai Law On High-Rise Buildings Needs Updating

[webfact]

Law on high-rise buildings needs updating

By Nalin Viboonchart

The Nation

The government needs to amend its 2007 regulations on high-rise buildings by increasing the type of structures required by law to withstand earthquakes and expand the decree's coverage.

In photo: Officials from a Chiang Mai administrative body inspect the damage caused to a high-rise building in the city after an earthquake hit Burma earlier this month. There are 40 buildings more than 15 stories high in downtown Chiang Mai. The current law, under which buildings should be able to withstand tremors of up to 5 on the Richter scale, only covers structures that are over 23 metres in height.

Dr Amorn Pimanmas, chairman of a panel on structural and bridge engineering at the Engineering Institute of Thailand, said the amendment was necessary given that there are buildings like manufacturing plants, boilers and chemical plants that can be severely damaged in a quake, which take place more often now.

Amorn said the regulation issued in 2007 had not been updated and that its coverage of building types and areas as risk was not comprehensive. Under the current law only buildings that are more than 23 metres in height and built after 2007 are required to withstand earthquakes. The law does not cover structures like manufacturing plants both inside and outside industrial estates, boilers and commercial buildings.

Besides, the law only covers five provinces in Central Thailand, namely Bangkok, Nonthaburi, Pathum Thani, Samut Prakan and Samut Sakhon, and a few others in the North and West of the country. In reality, there are other provinces in the region that have soft soil and face added risk of earthquakes such as Ayutthaya, Chachoengsao, Nakhon Nayok, Prachin Buri and Phetchaburi.

"Industrial estates are located in many provinces that have soft soil. This is a concern because some of these areas also have chemical plants, which have boilers or cooling towers. The recent earthquake in Burma, which also destroyed many buildings in the North, is good evidence that high-rise buildings in risky areas are not safe anymore. Some buildings in the North might also collapse with the aftershocks. Therefore, the government should amend the law so these buildings are adjusted to comply with the regulations and people can be protected from the possible dangers earthquakes," he said.

Amorn said there were up to 8,000 high-rise buildings in Bangkok and nearby provinces, not including the ones that were constructed before 2007. Buildings that were built before the 2007 regulation was issued can withstand a 4-Richter earthquake, while those built after 2007 can withstand a 5.3-Richter scale quake. The 2004 9.1-magnitude earthquake in Indonesia delivered a 4.5-5-Richter scale tremor to Bangkok.

Although Bangkok and other provinces in Central Thailand are not in the "ring of fire" they might still be affected if the Sagaing fault in Burma gets activated. If a high-magnitude quake occurs in Burma, one that is at least 6-Richter scale in magnitude might hit Bangkok.

"The state should be alert to this possible risk. We can prevent damage in the future by investigating high-rise buildings in risky areas and modifying them. It would be a very good solution to amend the law and cover all risky buildings and areas," he said.

Amorn recommended that owners wanting to strengthen their buildings use wire mesh to wrap the structure's pillars and apply cement on the mesh. This solution will only cost about Bt2,000 to Bt3,000 per pillar and will strengthen the building to withstand a quake of up to 5-Richter scale.

-- The Nation 2011-04-15

[bushwacker]

And yet another GREAT reason not to buy a condo in Thailand!

[Sunderland]

Where did the Nation get that photo of Chiang Mai? It has changed a lot since I was last there. Where did the sea come from?

[trogers]

And yet another GREAT reason not to buy a condo in Thailand!

I am comfortable with a low-rise condo building in BKK. The western fault line is a few hundred km west of BKK and most earthquake waves making their way here will be medium to low frequencies, coinciding with the natural frequencies of mid-rise and high-rise buildings.

[crusader79]

Dr Amorn Pimanmas, chairman of a panel on structural and bridge

engineering at the Engineering Institute of Thailand, said the amendment

was necessary given that there are buildings like manufacturing plants,

boilers and chemical plants that can be severely damaged in a quake,

which take place more often now.

Which take place more often now? Is that actually true for Thailand, or has he simply been watching a lot of CNN?

Edited April 15, 2011 by crusader79

[trogers]

Dr Amorn Pimanmas, chairman of a panel on structural and bridge

engineering at the Engineering Institute of Thailand, said the amendment

was necessary given that there are buildings like manufacturing plants,

boilers and chemical plants that can be severely damaged in a quake,

which take place more often now.

Which take place more often now? Is that actually true for Thailand, or has he simply been watching a lot of CNN?

If the plants are located near to fault lines, then the doctor is correct. If they are far ( a few hundred km or more), then the doctor had forgotten about models for dissipation of seismic waves.

[crusader79]

Which take place more often now? Is that actually true for Thailand, or has he simply been watching a lot of CNN?

If the plants are located near to fault lines, then the doctor is correct. If they are far ( a few hundred km or more), then the doctor had forgotten about models for dissipation of seismic waves.

You missed the point, which is whether or not quakes close enough to affect Thailand are 'taking place more often now'. Are they?

Edited April 15, 2011 by crusader79

[whybother]

And yet another GREAT reason not to buy a condo in Thailand!

Under the current law only buildings that are more than 23 metres in height and built after 2007 are required to withstand earthquakes.

Actually, it sounds like a good reason to by new high rise condo.

[trogers]

Which take place more often now? Is that actually true for Thailand, or has he simply been watching a lot of CNN?

If the plants are located near to fault lines, then the doctor is correct. If they are far ( a few hundred km or more), then the doctor had forgotten about models for dissipation of seismic waves.

You missed the point, which is whether or not quakes close enough to affect Thailand are 'taking place more often now'. Are they?

You have missed the point. Quakes occurring more often will not cause more damage if their intensities remain the same over similar distances.

Singapore's high-rise city will not topple if Sumatran quakes occur every 3 months instead of every two years, unless a scale 10 quake occurs.

[crusader79]

You have missed the point. Quakes occurring more often will not cause more damage if their intensities remain the same over similar distances.

Singapore's high-rise city will not topple if Sumatran quakes occur every 3 months instead of every two years, unless a scale 10 quake occurs.

The doctor supposedly stated that quakes 'take place more often now'. I am simply asking whether there is data to support that statement.

That the intensity of quakes decreases with distance is a completely different issue. And not exactly an 'earthshattering' observation, I might add.

Edited April 16, 2011 by crusader79

[Sabre]

Apparently medium-rise buildings of two to 10 floors are at more risk of damage from earthquakes than taller buildings. This is supposedly because the shorter buildings have a natural frequency closer to the frequency of seismic ground motion.

[Sabre]

Where did the Nation get that photo of Chiang Mai? It has changed a lot since I was last there. Where did the sea come from?

I would also add that at least some of it looks to be artificial (i.e. rendered).

[trogers]

Apparently medium-rise buildings of two to 10 floors are at more risk of damage from earthquakes than taller buildings. This is supposedly because the shorter buildings have a natural frequency closer to the frequency of seismic ground motion.

Only when these buildings are tens to a hundred km from the point of the quake, like those in provinces bordering the fault lines in Burma. Short seismic (high frequency) waves will quickly dissipate into heat over distance. The same reason you hear the rumble of the jet engines of a plane passing a km overhead, but not the whine.

Long seismic waves can travel great distance (over a thousand km) and affect high-rise buildings. Recall the Four Seasons complex in Bangkok suffered cracks on their walls from the 2004 Indian Ocean quake that also resulted in a tsunami.

[whybother]

Only when these buildings are tens to a hundred km from the point of the quake, like those in provinces bordering the fault lines in Burma. Short seismic (high frequency) waves will quickly dissipate into heat over distance. The same reason you hear the rumble of the jet engines of a plane passing a km overhead, but not the whine.

Long seismic waves can travel great distance (over a thousand km) and affect high-rise buildings. Recall the Four Seasons complex in Bangkok suffered cracks on their walls from the 2004 Indian Ocean quake that also resulted in a tsunami.

I don't recall, and can not find, any reports of damage in Bangkok from the 2004 earthquake.

[trogers]

Only when these buildings are tens to a hundred km from the point of the quake, like those in provinces bordering the fault lines in Burma. Short seismic (high frequency) waves will quickly dissipate into heat over distance. The same reason you hear the rumble of the jet engines of a plane passing a km overhead, but not the whine.

Long seismic waves can travel great distance (over a thousand km) and affect high-rise buildings. Recall the Four Seasons complex in Bangkok suffered cracks on their walls from the 2004 Indian Ocean quake that also resulted in a tsunami.

I don't recall, and can not find, any reports of damage in Bangkok from the 2004 earthquake.

Perhaps this small incident was overshadowed by news on the resulting tsunami. A developer client posted this question to us consultants in a project meeting as to why only the Four Seasons complex at Wireless road suffered some cracks, but not other high-rise buildings in Bangkok.

[whybother]

Perhaps this small incident was overshadowed by news on the resulting tsunami. A developer client posted this question to us consultants in a project meeting as to why only the Four Seasons complex at Wireless road suffered some cracks, but not other high-rise buildings in Bangkok.

Maybe your developer client heard rumours that cracks at the Four Seasons were caused by the earthquake, but were maybe caused by shoddy building.

[trogers]

Perhaps this small incident was overshadowed by news on the resulting tsunami. A developer client posted this question to us consultants in a project meeting as to why only the Four Seasons complex at Wireless road suffered some cracks, but not other high-rise buildings in Bangkok.

Maybe your developer client heard rumours that cracks at the Four Seasons were caused by the earthquake, but were maybe caused by shoddy building.

Correction on name of building. It was the All-Seasons at Wireless road.

http://winterson.com/archives/2004_06_01_archive.html

Edited April 17, 2011 by trogers

[geriatrickid]

And yet another GREAT reason not to buy a condo in Thailand!

I am comfortable with a low-rise condo building in BKK. The western fault line is a few hundred km west of BKK and most earthquake waves making their way here will be medium to low frequencies, coinciding with the natural frequencies of mid-rise and high-rise buildings.

And what risk does liquifaction present? I make reference of course to the soggy ground that is Bangkok.

If I recall, and correct me if I am wrong, the the quake that leveled Kobe had three important damage characteristics;

1. The ground becoming soggy for lack of a btter term;

2. Ensuing fires;

3. Collapse of lowrise unreinforced masonry structures

And what of the fires due to downed power lines, and ruptured gas lines that will follow a mild quake? Walk along some of the side sois off of Suhkumvit and you see multiple unreinforced masonry buildings. These structures would simply crumble. The streets would be impassable for rescue vehicles.

I am particularly concerned by the potential for toxic chemical leaks. If one looks at the flood damage in the south, the amount of pertrochemicals, pesticides, herbicides and heavy metals that have spread out and now contaminate the soil and ground water is frightening. Of course, not a word of this aspect of the floods gets mentioned in the local media. Imagine if the chemical tanks at some of the Bangkok region's manufacturers ruptured. Is Bangok able to deal with massive releases of Chorine or ammonia gases? How about strong acids or caustic chemicals?

Mummy, I'm scared.

[whybother]

Correction on name of building. It was the All-Seasons at Wireless road.

I still can't find any reference to damage in Bangkok.

[trogers]

And yet another GREAT reason not to buy a condo in Thailand!

I am comfortable with a low-rise condo building in BKK. The western fault line is a few hundred km west of BKK and most earthquake waves making their way here will be medium to low frequencies, coinciding with the natural frequencies of mid-rise and high-rise buildings.

And what risk does liquifaction present? I make reference of course to the soggy ground that is Bangkok.

If I recall, and correct me if I am wrong, the the quake that leveled Kobe had three important damage characteristics;

1. The ground becoming soggy for lack of a btter term;

2. Ensuing fires;

3. Collapse of lowrise unreinforced masonry structures

And what of the fires due to downed power lines, and ruptured gas lines that will follow a mild quake? Walk along some of the side sois off of Suhkumvit and you see multiple unreinforced masonry buildings. These structures would simply crumble. The streets would be impassable for rescue vehicles.

I am particularly concerned by the potential for toxic chemical leaks. If one looks at the flood damage in the south, the amount of pertrochemicals, pesticides, herbicides and heavy metals that have spread out and now contaminate the soil and ground water is frightening. Of course, not a word of this aspect of the floods gets mentioned in the local media. Imagine if the chemical tanks at some of the Bangkok region's manufacturers ruptured. Is Bangok able to deal with massive releases of Chorine or ammonia gases? How about strong acids or caustic chemicals?

Mummy, I'm scared.

You are painting a scenario of a quake occurring not far from Bangkok. Like a volcano erupting near LA...lol

[ableguy]

Most Thai laws need updating but why bother ? nobody seems to care about laws.

[ableguy]

And yet another GREAT reason not to buy a condo in Thailand!

I am comfortable with a low-rise condo building in BKK. The western fault line is a few hundred km west of BKK and most earthquake waves making their way here will be medium to low frequencies, coinciding with the natural frequencies of mid-rise and high-rise buildings.

And what risk does liquifaction present? I make reference of course to the soggy ground that is Bangkok.

If I recall, and correct me if I am wrong, the the quake that leveled Kobe had three important damage characteristics;

1. The ground becoming soggy for lack of a btter term;

2. Ensuing fires;

3. Collapse of lowrise unreinforced masonry structures

And what of the fires due to downed power lines, and ruptured gas lines that will follow a mild quake? Walk along some of the side sois off of Suhkumvit and you see multiple unreinforced masonry buildings. These structures would simply crumble. The streets would be impassable for rescue vehicles.

I am particularly concerned by the potential for toxic chemical leaks. If one looks at the flood damage in the south, the amount of pertrochemicals, pesticides, herbicides and heavy metals that have spread out and now contaminate the soil and ground water is frightening. Of course, not a word of this aspect of the floods gets mentioned in the local media. Imagine if the chemical tanks at some of the Bangkok region's manufacturers ruptured. Is Bangok able to deal with massive releases of Chorine or ammonia gases? How about strong acids or caustic chemicals?

Mummy, I'm scared.

Go home pussy

[whybother]

And what risk does liquifaction present? I make reference of course to the soggy ground that is Bangkok.

If I recall, and correct me if I am wrong, the the quake that leveled Kobe had three important damage characteristics;

1. The ground becoming soggy for lack of a btter term;

2. Ensuing fires;

3. Collapse of lowrise unreinforced masonry structures

And what of the fires due to downed power lines, and ruptured gas lines that will follow a mild quake? Walk along some of the side sois off of Suhkumvit and you see multiple unreinforced masonry buildings. These structures would simply crumble. The streets would be impassable for rescue vehicles.

I am particularly concerned by the potential for toxic chemical leaks. If one looks at the flood damage in the south, the amount of pertrochemicals, pesticides, herbicides and heavy metals that have spread out and now contaminate the soil and ground water is frightening. Of course, not a word of this aspect of the floods gets mentioned in the local media. Imagine if the chemical tanks at some of the Bangkok region's manufacturers ruptured. Is Bangok able to deal with massive releases of Chorine or ammonia gases? How about strong acids or caustic chemicals?

Mummy, I'm scared.

What gas lines?

The quake that leveled Kobe occurred only 20 km away. That is not a likely occurrence in Bangkok.

[MaiChai]

Most Thai laws need updating but why bother ? nobody seems to care about laws.

Yup, not mention city planning and zoning of business/industrial and residential. Life is cheap in SE Asia and nothing should be in the way of profit. Example: those shops that store cooking gas cylinders.

[Sabre]

Apparently medium-rise buildings of two to 10 floors are at more risk of damage from earthquakes than taller buildings. This is supposedly because the shorter buildings have a natural frequency closer to the frequency of seismic ground motion.

Only when these buildings are tens to a hundred km from the point of the quake, like those in provinces bordering the fault lines in Burma. Short seismic (high frequency) waves will quickly dissipate into heat over distance. The same reason you hear the rumble of the jet engines of a plane passing a km overhead, but not the whine.

Long seismic waves can travel great distance (over a thousand km) and affect high-rise buildings. Recall the Four Seasons complex in Bangkok suffered cracks on their walls from the 2004 Indian Ocean quake that also resulted in a tsunami.

Ah, thanks for the clarification.

Yes I remember it ... at the time there was a great deal of concern ... I forget which tower it was though ....

[Sabre]

Most Thai laws need updating but why bother ? nobody seems to care about laws.

Exactly. But we've got to start somewhere ....

[geriatrickid]

What gas lines?

The quake that leveled Kobe occurred only 20 km away. That is not a likely occurrence in Bangkok.

How do you think most urban residents in the low end buildings or restaurants cook food?

You know all those portable gas cylinders that restaurants use? They are big and are not always properly secured, nor are they equipped with emergency shut off valves

Apparently there are 13 active faults across 22 provinces, with 308 districts, in Thailand. Bangkok is less than 200 kilometres from the Chedi Sam Ong fault line, and about 800km from the Mae Ta and Mae Chan fault lines are located. These are the most active fault lines in Thailand.Pennung Warnitchai, a seismologist from the Asian Institute of Technology, has stated that there is a high possibility a powerful earthquake of 6-7 magnitude will occur along the fault lines in Kanchanaburi and Chiang Mai provinces. He also states that a severe earthquake ion these fault lines would cause severe damage to Bangkok,

You think there is no risk because the fault lines are not close? Do you know what distinguishes Bangkok? Its soil. Its soft and in many parts clay.Mexico Ciy has similar soil. Do you remember what happened in Mexico City in 1985 when an earthquake 450km from the city occurred? 9000 people died and thousands of structures collapsed.

So, what's your point on the distance?

[trogers]

You think there is no risk because the fault lines are not close? Do you know what distinguishes Bangkok? Its soil. Its soft and in many parts clay.Mexico Ciy has similar soil. Do you remember what happened in Mexico City in 1985 when an earthquake 450km from the city occurred? 9000 people died and thousands of structures collapsed.

So, what's your point on the distance?

Seen the Discovery documentary video about 3 quakes: Frisco, Kobe and Mexico City. The main problem at Mexico City was the mid-rise buildings being built too close to each other and they hit during the swaying. Most low-rise did not crumble.

[whybother]

What gas lines?

The quake that leveled Kobe occurred only 20 km away. That is not a likely occurrence in Bangkok.

How do you think most urban residents in the low end buildings or restaurants cook food?

You know all those portable gas cylinders that restaurants use? They are big and are not always properly secured, nor are they equipped with emergency shut off valves

Apparently there are 13 active faults across 22 provinces, with 308 districts, in Thailand. Bangkok is less than 200 kilometres from the Chedi Sam Ong fault line, and about 800km from the Mae Ta and Mae Chan fault lines are located. These are the most active fault lines in Thailand.Pennung Warnitchai, a seismologist from the Asian Institute of Technology, has stated that there is a high possibility a powerful earthquake of 6-7 magnitude will occur along the fault lines in Kanchanaburi and Chiang Mai provinces. He also states that a severe earthquake ion these fault lines would cause severe damage to Bangkok,

You think there is no risk because the fault lines are not close? Do you know what distinguishes Bangkok? Its soil. Its soft and in many parts clay.Mexico Ciy has similar soil. Do you remember what happened in Mexico City in 1985 when an earthquake 450km from the city occurred? 9000 people died and thousands of structures collapsed.

So, what's your point on the distance?

You were comparing Kobe, where the earthquake happened 20 km away, to possible earthquake affecting Bangkok from more than 200km away.

You are also comparing Mexico City, where a magnitude 8.1 quake caused damage, to a high possibility 6-7 magnitude quake that might affect Bangkok. Compare the main recent Japan quake of 9.0, which caused a large amount of damage (not including the tsunami) to previous and following 6-7 quakes around the same location that caused very little damage.

Re: gas lines. I thought you were talking about major gas pipes running underground delivering gas to households and businesses, not gas bottles.

[trogers]

If I recall, and correct me if I am wrong, the the quake that leveled Kobe had three important damage characteristics;

1. The ground becoming soggy for lack of a btter term;

2. Ensuing fires;

3. Collapse of lowrise unreinforced masonry structures

A large loss of lives during the Kobe quake was due to collapses of single and double levels homes. The reason is the very heavy tiled japanese roofs used which were good resisting typhoons but deadly in an earthquake.