MEL1

... a degreed civil engineer here... structural ... don't know it all, but do know a good bit about the subject.

... without inspecting the damages, we can only speculate on causes of the Suvarnabhumi runway failures ... but, this does not sound favorable for the AOT and Thailand's reputation as a nation capable of achieving international standards.

... a few observations ... basics:

• Concrete does not flex well... it is designed to sustain tremendous compression loads, so dropping a fully loaded A380 at 200 knots onto its surface is no problem for properly designed and constructed concrete runways; however,
  
• When subject to significant flexural (bending) loads, concrete fractures ... rather easily, actually ... concrete failure is not a slow, plastic bending, but a sharp dramatic failure ... the steel reinforcing bars embedded in the concrete is placed there to sustain the bending loads, called 'moment loads', that concrete cannot resist.
  

... what is described in the article above is a 60cm x 60cm section subsiding 5cm ... it sounds as a "punching" failure ... this is not the slow subsiding we are witnessing throughout Thailand ... the article does not describe a smooth flexing, which concrete cannot do, as with pliant materials (wood, metal, plastic, etc.) ... the article describes a concrete slab that cracked, separated and dropped 5cm below the level of the surfaces around it ... nothing about this form of concrete "punching" failure (if that is what this is) is normal ... it is not maintenance related ... it would be a dramatic structural failure.

... but a runway failure of this type should not be misconstrued as the problem ... it is not ... the runway failure as this is a symptom of a much greater problem ... the symptom could be caused by a couple of most likely sources:

• The higher probability is that inferior foundations are the most likely symptom of the problem ... no matter how competently the runway slab is designed and built, it is predicated on having a firm foundation ... a failed foundation almost invariably results in failed structures that sit upon them ... because the compacted substrate, subsoil drainage system and pilings (which I presume they used in a swamp) cannot be 100% tested (only sampled), there is a huge exposure here;
  
• Less likely is an inferior runway slab itself ... slab design is fairly straight-forward ... very well-developed, proved construction technology, materials and design standards ... the key is the foundation.
  

... the greater problem of a runway failure as this, as opposed to the symptoms of the problem, could in my view include the following, in order of likelihood:

• Most likely, is inferior quality construction practices ... not installing materials in conformance to the design... this could be simple gross mismanagement, which I've heard is not so unheard of here in Thailand ('mai pen rai' ... 'do just enough'... 'aww, you tink too mutt') ... or, if a Thai contractor did have larceny in him, relatively few co-conspiritors would have to be recruited to get away with taking inferior short cuts ... this is particularly possible when a great deal of work is done in the cool of the night, as was I believe the case here;
  
• A bit less likely, is inferior construction materials ... low-strength concrete, or low-strength reinforcing steel ... in an environment of corruption and incompetence, substituting inferior construction materials is a distinct possibility ... however, the safety factors applied in the design of structures (to international design standards) are quite forgiving ... if inferior materials were substituted, they would be substituted to massive degrees to cause a failure as this;
  
• Least likely, is inferior design ... engineers in Thailand are personally liable (civilly and criminally) for damages and deaths caused by the failures of structures they design ... to protect themselves, Thai engineers are understandably notorious for overdesigning structures to account for the corrupt building practices indemic in Thailand ... and, as mentioned above, international design standards include significant factors of safety that will forgive a measure of inferior construction practices and materials.
  

... but, going back to the top, if this runway failure is as described in the article (a 'punching' failure), this failure could well be the harbinger of a chronic decay of the runway, now underway ... unlikely that it is an isolated failure, but representative of how the entire runway was constructed.

... open 6 years now, major deficiencies at Suvarnabhumi Airport continue to mount ... these are not the isolated sort of corrections expected at the opening of new projects ... these are deeply flawed, fundamental systems deficiencies reflective of a broader mentality ... that is a concern.

... the Thai government is trying to remedially correct them, which is always inferior to doing them correctly in the first place ... leaky roof ... insufficient air-conditioning ... fire safety violations ... too few bathrooms ... radar and air traffic control system failures ... back-up power system failures ... spalling runway concrete ... insufficiently drained, highly expansive subsoils ... under-designed passenger capacity ... forget the ongoing operational problems, this is just the hardware.

... the world's latest technology, most experienced consultants and best contractors and suppliers were available to Thailand in launching it's greatest public infrastructure achievement to date ... Thailand's front door and calling card to the world is suffering signs of obsolesence ... it is 5-1/2 years old.

... anything anyone needs to know about this nation, doing business or living here, is neatly packaged in the story of the building of Thailand's Suvarnabhumi International Airport ... a remarkable story, truly.

As a degreed civil engineer, why have you not gone into detail about subsidence, the causes of it - re building on swamp land, the dispersion of water from the supporting sub-strates (sand and limestone in this case), the causes of air pockets and sub-support ground failure when the water which supports those substrates is dispersed, tapped, drained, and so on as the list goes on.

I was hoping for some asertions from a 'civil' engineer to some of my previous posts and statements, which I sourced from general knowledge, and even quoted an internet source.

Would you care to go into detail about the subsidence happening below the concrete slabs, as I think most don't have a problem with the runway surface construction.

-mel.

Mel

Lets be fair, the post by swillowbee is quite awesome and full of excellent information. If he types like me it probably took 25 mins and a cup of coffee. The additional info you want would be great but give the guy a chance, only so many hours in the day eh!

I like you understand that the geology is the issue, What swampy does not want is very wet rainy seasons followed by prolonged periods of heat and drought. The subsequent fall in the level of the water table and the accompanied 'shrinkage' are the conditions that could see gaping holes appear, but in the nature that swillowbee describes, sudden, violent and dramatic, and enough to ruin your day if you are in the stages of a take off run or landing.

To give you an idea of how dramatic and sudden these things occur when the wrong geology is in place, check out the mother below that opened in Guatemala after a tropical storm!!! Photoshop not involved!

It was exactly this kind of extreme scenario and those in Florida that I wan't referring to though mate.

It's the constant smaller troughs that develop all over the place, roads sinking in BKK and everywhere as a result of poor substructure laying, and a non-undertsanding of sedimentary requirements below, in the first place, that's the worry. For this to be now happening below runways..... well... I have no words really to explain the catostrophes awating, nor the ignorance of the authorities to just cover them up with blind blankets of what they believe is crack filling as the ultimate answer.

Oh! and Edit: No disrespect to you swillowbee, I was looking for further evidence of the ground subsidence and not surface failure, from a qualified person.... thaz all folks!

... a degreed civil engineer here... structural ... don't know it all, but do know a good bit about the subject.

... without inspecting the damages, we can only speculate on causes of the Suvarnabhumi runway failures ... but, this does not sound favorable for the AOT and Thailand's reputation as a nation capable of achieving international standards.

... a few observations ... basics:

• Concrete does not flex well... it is designed to sustain tremendous compression loads, so dropping a fully loaded A380 at 200 knots onto its surface is no problem for properly designed and constructed concrete runways; however,
  
• When subject to significant flexural (bending) loads, concrete fractures ... rather easily, actually ... concrete failure is not a slow, plastic bending, but a sharp dramatic failure ... the steel reinforcing bars embedded in the concrete is placed there to sustain the bending loads, called 'moment loads', that concrete cannot resist.
  

... what is described in the article above is a 60cm x 60cm section subsiding 5cm ... it sounds as a "punching" failure ... this is not the slow subsiding we are witnessing throughout Thailand ... the article does not describe a smooth flexing, which concrete cannot do, as with pliant materials (wood, metal, plastic, etc.) ... the article describes a concrete slab that cracked, separated and dropped 5cm below the level of the surfaces around it ... nothing about this form of concrete "punching" failure (if that is what this is) is normal ... it is not maintenance related ... it would be a dramatic structural failure.

... but a runway failure of this type should not be misconstrued as the problem ... it is not ... the runway failure as this is a symptom of a much greater problem ... the symptom could be caused by a couple of most likely sources:

• The higher probability is that inferior foundations are the most likely symptom of the problem ... no matter how competently the runway slab is designed and built, it is predicated on having a firm foundation ... a failed foundation almost invariably results in failed structures that sit upon them ... because the compacted substrate, subsoil drainage system and pilings (which I presume they used in a swamp) cannot be 100% tested (only sampled), there is a huge exposure here;
  
• Less likely is an inferior runway slab itself ... slab design is fairly straight-forward ... very well-developed, proved construction technology, materials and design standards ... the key is the foundation.
  

... the greater problem of a runway failure as this, as opposed to the symptoms of the problem, could in my view include the following, in order of likelihood:

• Most likely, is inferior quality construction practices ... not installing materials in conformance to the design... this could be simple gross mismanagement, which I've heard is not so unheard of here in Thailand ('mai pen rai' ... 'do just enough'... 'aww, you tink too mutt') ... or, if a Thai contractor did have larceny in him, relatively few co-conspiritors would have to be recruited to get away with taking inferior short cuts ... this is particularly possible when a great deal of work is done in the cool of the night, as was I believe the case here;
  
• A bit less likely, is inferior construction materials ... low-strength concrete, or low-strength reinforcing steel ... in an environment of corruption and incompetence, substituting inferior construction materials is a distinct possibility ... however, the safety factors applied in the design of structures (to international design standards) are quite forgiving ... if inferior materials were substituted, they would be substituted to massive degrees to cause a failure as this;
  
• Least likely, is inferior design ... engineers in Thailand are personally liable (civilly and criminally) for damages and deaths caused by the failures of structures they design ... to protect themselves, Thai engineers are understandably notorious for overdesigning structures to account for the corrupt building practices indemic in Thailand ... and, as mentioned above, international design standards include significant factors of safety that will forgive a measure of inferior construction practices and materials.
  

... but, going back to the top, if this runway failure is as described in the article (a 'punching' failure), this failure could well be the harbinger of a chronic decay of the runway, now underway ... unlikely that it is an isolated failure, but representative of how the entire runway was constructed.

... open 6 years now, major deficiencies at Suvarnabhumi Airport continue to mount ... these are not the isolated sort of corrections expected at the opening of new projects ... these are deeply flawed, fundamental systems deficiencies reflective of a broader mentality ... that is a concern.

... the Thai government is trying to remedially correct them, which is always inferior to doing them correctly in the first place ... leaky roof ... insufficient air-conditioning ... fire safety violations ... too few bathrooms ... radar and air traffic control system failures ... back-up power system failures ... spalling runway concrete ... insufficiently drained, highly expansive subsoils ... under-designed passenger capacity ... forget the ongoing operational problems, this is just the hardware.

... the world's latest technology, most experienced consultants and best contractors and suppliers were available to Thailand in launching it's greatest public infrastructure achievement to date ... Thailand's front door and calling card to the world is suffering signs of obsolesence ... it is 5-1/2 years old.

... anything anyone needs to know about this nation, doing business or living here, is neatly packaged in the story of the building of Thailand's Suvarnabhumi International Airport ... a remarkable story, truly.

As a degreed civil engineer, why have you not gone into detail about subsidence, the causes of it - re building on swamp land, the dispersion of water from the supporting sub-strates (sand and limestone in this case), the causes of air pockets and sub-support ground failure when the water which supports those substrates is dispersed, tapped, drained, and so on as the list goes on.

I was hoping for some asertions from a 'civil' engineer to some of my previous posts and statements, which I sourced from general knowledge, and even quoted an internet source.

Would you care to go into detail about the subsidence happening below the concrete slabs, as I think most don't have a problem with the runway surface construction.

-mel.

Let us build a F1- circuit!!!!

We have one it go's all the way around the moat. Exiting to watch during songkrahn. Does any one know what Tsongkhapa is? I got that on my spell checker when I checked Songkhran.

-mel.

MEL 1

The sub-surface will get worse, if water dispersion continues. The sub-waters are actually an asset at the moment, as they hold the supporting the supporting materials, and in this case a lot of sand. Once the waters start to disperse that's when the supporting materials develeop major holes, and holes in them disappear. This is all a normal part of subsidence. It's not a normal function to use limestone and sand as supporting matter for an airport runway, on a swamp. The virginal pressures of when built, to now, will have been dispersed and we are just seeing the initial results of that over the last years. There is the propensity for sinkholes the size of football fields and 40m deep to occur at any time if a large water dispersion occurs. You only have to look at the major sinkholes that have occured in Florida, with houses and pools disappearing, in one case a sink hole 100m deep occured and took a building block to get an idea.

-mel.

Or it could be a bitumen surface problem.

Well I agree what you say has some merit. How ever is not the whole area (Bangkok) sinking to below the sea level and would not each little bit of sinking make the chances of the water leaving the area and creating huge sink holes less likely to happen.

With my experience in road building I would not have even attempted to build a airport of that size there as there is no way of getting proper compaction on a area that big.

But the one thing I did learn was that engineers had ways to work around some difficulties that would not occur to the normal person.

Don't get me wrong I have had my differences of opinion with them and been right on occasion but not all the time.

Just found this very short interesting study, which also mentions BKK.

http://wwwrcamnl.wr.usgs.gov/rgws/Unesco/PDF-Chapters/Chapter1.pdf

-mel.

And Swampy gets 200 times more heavy traffic than Utapao every day, maybe even more. Oh and yes the US built it

And traffic is not necessarily the cause of sink holes, poor design and forethought is. At that time, B-52's fully loaded are 'heavy' and daily traffic was high but still nothing happened.

True, it is just heavy, regular repeated traffic may make the problem become apparent sooner. The sink holes are caused by the effectiveness (or lack of) of the sub surface drainage. I have been told that the subsurface composition in the area experiences quite severe extremes of shrinkage then water logging depending on seasonal conditions. If the US/US military had been contracted to build the runway at swampy, I doubt there would be any issues at all. One poster has rightly said that the sinkhole issues should not really be appearing within 5 years of runway use. Wait for another 5-10 years to see the state of the sub surface then.

And yes, airports world-wide resurface and repair their runways, but generally those problems are superficial and not involving major sub surface problems like those rumored to exist at swampy.

I see no reason for the state of the sub surface to be any different in 5 to 10 years than it is now. That is providing we don't get a major flood every year.

The sub-surface will get worse, if water dispersion continues. The sub-waters are actually an asset at the moment, as they hold the supporting the supporting materials, and in this case a lot of sand. Once the waters start to disperse that's when the supporting materials develeop major holes, and holes in them disappear. This is all a normal part of subsidence. It's not a normal function to use limestone and sand as supporting matter for an airport runway, on a swamp. The virginal pressures of when built, to now, will have been dispersed and we are just seeing the initial results of that over the last years. There is the propensity for sinkholes the size of football fields and 40m deep to occur at any time if a large water dispersion occurs. You only have to look at the major sinkholes that have occured in Florida, with houses and pools disappearing, in one case a sink hole 100m deep occured and took a building block to get an idea.

-mel.

Or it could be a bitumen surface problem.

So much rubbish posted in response to this story. The problem of cracking and stripping (where the bitumen comes away from the concrete below) is common. The issue here is the maintenance schedule. The sky is not falling. It is not the end of the world. Once the maintenance schedule is sorted everything will be fine. It is normal to have runways closed for resurfacing and repair work. I believe Sydney airport had a runway closed for nearly a year with maintenance and repair works taking place.

It's April fools right? You're having a larff? Surely?

-mel.

Well, actually, the worst mistake he made was to publicly announce that he had manipulated Thaksin!

Big mistake...

-mel.

Thaksin is a key, and a gateway, to Chinese negotiations and information about insider Asian business deals.

I'm sure that is of some interest to US intelligence, or some intelligence that exists in politics.

-mel.

Interflora operates here in Thailand, as much as anywhere else....

-mel.

I didn't actually see any useful prizes. A truck wash, when I own a car??

150 Baht towards a meal at the golf club, where a meal is prob 500 Baht up..., and a place I wouldn't frequent.

I certainly didn't see an iphone 4S on the redeemable prizes page...... is there a special link to that prize?

If there were physical things to collect or win then I'd be a lot more interested... but the bits and bobs that are currently listed as prizes don't really warrant any effort to collect points at this moment in time. IMHO

-mel.

The opposition just needs to make a few diagonals, turn this into a Queen's gambit, and see how long it is before she retires and the real endgame begins!

-mel.

So where are these people going to get 100m Baht from?

Oh, yes. Put them back on duty, once they've been tried.... and let them rake up their dosh from other illegal pursuits, such as fining the innocent etc...

Just not funny!

-mel.

Nothing to worry about yet. If it gets to be a real problem send for Chalerm and he'll have it eradicated in 90 days, even if he has to shoot every bird himself.

dam_n it, eradicating on chewing birds was a Chuwit thingy-ma-jig. I hope Chalerm doesn't shoot all of Chuwit's birds, as some were tasty.... and never gave a night fever. However, Chuwit's adverts against pigs, and swine-yoo-fool-flu is on the right track, isn't it? A tissue, a tissue, we all fell down, said dek Chalerm..... the gun with no name.

-mel.

Health Minister Witthaya Buranasirin doesn't look too well, does he?

Fever, headache, tiredness.... I wonder if he ate 'gai' whilst visiting the so called egg infected areas of puying BKK?

-mel.

Does this mean the government is going to get on with working for the people now?

You know who the people 'IS', don't you?

Yes, by all means, it will carry on working for the 'people'.

-mel.

PTP are about as patient as an Isuzu 4x4 driver at a set of lights in second place behind a songtao!

-mel.

Wifey hates them, I can't se what the problem is.

Anyway, my wife went along to one of the garden supply shops and bought some kind of liquid that she mixed with water and sprayed on the tiles all around the outside of the house.

The millipedes were dieing for a couple of weeks after that so I hate to think what was in the stuff.

Sent from my GT-I9003 using Thaivisa Connect App

where did your wife bought the solution????

can you be so kind as to take a photo of it????

thanks!!!!

.

Wifey says it is a general bug killer and comes in a flask type metal bottle painted silver.

Sent from my GT-I9003 using Thaivisa Connect App

A metal bottle painted silver? Please find the manufacturer, as I can save them a production cost fortune.

-mel.

10/1 on that nothing gets done!

-mel.

15 witnesses to testify in the two-day inquiry on the charter amendment bill. Seven witnesses are allowed to testify against charter change.

Eight witnesses to testify for the charter?

If so, it looks like an already done deal...

Ever seen an expected penalty shoot-out go wrong?

-mel.

RT @191Thailand: The BKK-Koh Pha Ngan tour bus left Bangkok at 7:30pm last night. There were 24 passengers & 3 bus staff.

RT @191Thailand: Latest news on 10 dead in bus crash: 5 foreign tourists (1 male and 4 female), 4 Thai tourists (4 male) and the driver.

Post Today reporting that 6 of the dead are foreign tourists (1 male & 5 female). The rest are Thai including the driver

Tragic, but 10 people and an indian ? Really !

It's relevant, because that's two Indians suffering in the news this week.

sent from my new Galaxy S3.

-mel.

As an ex-automobile interior design expert, and crash expert, I am amazed at how many experts are here at TV giving qualified opinion.

There is nothing to indicate that the bus was travelling at high speed, despite what many see as carnage.

Get a grip, and stop giving inadequate analysis, yet again, about thesis and guesses.

Farang have died here, and that is relative to our posting. Otherwise, you'd be posting about every van and bus crash every day.

May their families cope with their loss/es, and some hope of true events as to the cause of the crash be disclosed.

-mel.

I travel in vip buses a lot, and I'm always the only person wearing a seatbelt. It amazes me how nobody else buckles up. These buses go pretty darn fast!

BTW, what's the safest seat in one of those buses?

-mel.

Plop-dra-soup is having a whacko-jacko moment.

What scares me is all these continous weekly hundrdeds of millions, with no end to the soup dragon's depth of bowl, with her gnashing teeth on a back-hander, and she approves and approves team after team - cos she aint got a clue!

Little achieved, with false results left, right and centre; and a government fast approaching an empty wallet, little can they see that far past their own wallets.

There's gonna be a cruch time sooner than later...

-mel.

(NASA to pick up the pieces?)