Paris CDG Roof Collapse (merged)

[Airbubba]

Looks like the rest of the terminal may be razed...

_____________________________________________

May 24, 2004

Cracking Sounds Heard at Paris Airport
By THE ASSOCIATED PRESS

Filed at 12:32 p.m. ET

ROISSY, France (AP) -- A day after a deadly roof collapse, new cracking sounds were heard Monday inside a terminal at Paris' Charles de Gaulle airport, and dozens of workers there were evacuated.

The scare came as officials said they were considering scrapping the entire Air France Terminal 2E after a 98-foot section of the steel, concrete and glass roof caved in at about 7 a.m. Sunday, killing four people. The terminal is closed indefinitely.

More than 30 people in airport offices and a nearby restaurant were evacuated Monday when the new cracking sounds were heard, airport director Rene Brun said. Airport staff will not be allowed inside until an analysis is completed, Brun said.

Cracking and puffs of dust minutes before Sunday's accident had proved a warning sign.

The area evacuated Monday is a separate structure from the tube-shaped boarding and waiting area where the roof partially collapsed. It is joined by small walkways. A third structure in the complex is reserved for checking in.

``We feared that there would be another problem,'' said Corinne Bokobza, spokeswoman for the airport authority, known as ADP. ``We're taking no risks.''

The $890 million terminal was touted as a jewel of design, safety and comfort when it opened 11 months ago after several delays that the French TV network LCI said were due to safety issues.

Officials initially believed five were killed in the collapse, but lowered the death toll after searching through rubble. Two of the dead were Chinese travelers on a stopover at Charles de Gaulle on route from Shanghai to Mexico via Paris, the Chinese government said.

Three people were slightly injured -- all police officers or security personnel called to the scene when cracking appeared minutes before the collapse of a portion of the terminal's roof. They began evacuating people from the area minutes before the accident, perhaps sparing lives.

The collapse has been an embarrassment for French authorities.

The building, the pride of the airport, could be razed if investigations prove it cannot be made safe, the head of the airport authority said.

``If all these rings that make up this terminal are irrecoverable, we'll tear it all down, of course,'' Pierre Graff was quoted in daily Le Parisien daily as saying, referring to steel rings that form a spine in the building. ``We will take no risks when it comes to security.''

The futuristic building is a tube-like structure of concrete, steel and glass, hundreds of feet long, that stands on pylons above the ground. The ceiling is honeycombed with hundreds of square windows that flood it with light. With slots for 17 aircraft, the terminal was designed to handle 10 million passengers a year.

The collapse involved a 100-foot section of the roof, preceded by several loud cracking sounds. As the roof fell onto a waiting area, it pulled down walls and crashed through a boarding ramp onto several parked cars below.

``We are very touched by the cruelty of this collapse,'' Prime Minister Jean-Pierre Raffarin said as he examined the site. Investigations ``will bring out the truth,'' he added.

Two investigations, administrative and judicial, were underway, and experts from some of the 400 companies that participated in the terminal's construction went to the scene.

One hypothesis being studied is whether the ground underneath the terminal had settled, LCI television reported.

Paul Andreu, the terminal's architect, was returning to Paris from Beijing, where he is working on a project to build the National Theater of China, said an assistant, Patricia Casse.

``I am completely stunned,'' Andreu was quoted as saying in Monday's edition of the French Communist daily L'Humanite. ``I cannot explain what happened. I don't understand.''

Francois Charrita, assistant director of operations at ADP, told France-Info radio, that ``without a doubt'' the investigations would focus on potential problems with construction.

A fault in design would, on the other hand, be unlikely because of multiple controls by experts, including independent ones, he said.

[BahrainLad]

In the same way as some doctors carry malpractice insurance, do architects/contractors carry the same?

Even if, would such a policy cover (gulp) €750 million??

[FOZ]

If you look closely at the pictures so far, it appears that the concrete elipses are still generally intact but now at ground level. It also appears that the concrete joist that ran between the pillars supporting the structure is no longer present. Could this be a catastrophic failure of that prestressed concrete joist?

[Flightmapping]

Yes, architects would carry insurance, as would all the other contractors. I have to admit to being shocked when I first heard about this.

Building collapses caused by structural defects, as opposed to earthquakes, fire or acts of terrorism are extremely rare.

I was just telling someone about Ronan Point, which was perhaps the last serious structural failure in the UK? (AFAIK)

Of course, lessons will be learnt from this tragic occurence, but to put it in perspective I was always taught (at Architecture school) that to make staying indoors as risky as going outside, you'd have to slow all traffic down to 3mph.

So, those unfortunate souls who were trapped by this collapse were indeed very, very unlucky.

[ATC Watcher]

Very sad indeed . As a regular ( and frequent ) user of Terminal 2, I have used the walkway many times and never thought about its possible collapse .
According one news speculator in French TV, the terminal was evacuated just prior the collapse, thus limited the number od casualties...who were mostly chinese apparently.
According the same news speculator , The pillars that support the structure are n likely to be the cause, as some of them were showing cracks , and were reinforced by carbon rings , during the construction .

Condoleances to the famillies.

[OFBSLF]

n the same way as some doctors carry malpractice insurance, do architects/contractors carry the same?

Yes, architects, contractors, and engineers carry errors and omissions insurance. Their contracts often limit try to limit their liability, however. Here in the colonies, contract language typically limits their liability to their fee. Whether or not those limits hold in court is well beyond my expertise.

While press are talking about the architect, it is the engineering and construction that are more likely to be the issue. The structural and geotechnical engineers are responsible for ensuring that the structure will stand up (provided it is constructed as designed and with proper materials). The job of the engineers is often made more difficult due to the architect's whims, but it is still their job to ensure that the design is sound, no matter what monstrosity the architect sold to the client.

The cause of the failure could have been:

- bad structural design
- bad foundation design
- faulty construction (i.e., not built to the design)
- faulty materials

We'll have to wait for the investigation to determine just what the problem was.

OFBSLF (used to be a Geotechnical Engineer in a previous life)

[pdalla]

I have spent many an hour gazing out of the east (maybe SE) facing window of the AF FF lounge in the bowels of 2E looking at the construction work happening adjacent to the new terminal (no perverse pleasure here, just long transits due to missed connections).

Thought crosses my mind whether all that work digging away at nearby ground, and if I recall correctly some of it was concrete apron, affected the new structure. Bit like causing a local earthquake maybe. I have a friend here in ATL whose house was similarly affected by adjacent building work on a neighbour's foundations, causing damage to his house as if a major earthquake had rocked his house. He was lucky though, his house was mostly built of wood and it only got a little bent out of shape. Concrete however would not be so forgiving.. Didn't ADP also build a tunnel round there somewhere ?

[Evening Star]

I have a friend here in ATL whose house was similarly affected by adjacent building work on a neighbour's foundations, causing damage to his house

Back in the days when ES was a student surveyor learning all aspects of the science, one regular task was to carry out schedules of condition on buildings adjacent to proposed building work. Very boring work that was, but one became quite an expert at spotting even the smallest crack. Quite common in the UK, and if anything does move it provides evidence for any claim to reinstate the damaged property.

In the same way as some doctors carry malpractice insurance, do architects/contractors carry the same?

Even if, would such a policy cover (gulp) €750 million??

To reiterate the answer about insurance, yes. It is compulsory requirement by my professional organisation and bloody expensive it is as well. After the mortgage, it is the second most expensive outgoing in the ES family budget, and that is for my modest needs in the relatively safe area of hydrology.

As for how much cover, it is possible that the organisations involved in projects of this size will have that level of cover. In any case, any claim will be spread between the various parties (architect, engineer, contractor), so any individual organisation will not have to carry the full 750m.

Ronan Point, which was perhaps the last serious structural failure in the UK? (AFAIK)

There have been a few serious failures since then, although all that I can recall were the result of a fire or explosion rather than a simple structural failure. However, even Ronan Point was not a simple building collapse, but a gas explosion exposing substandard design and construction.

Point is that these things rarely have a single cause and it is worth waiting for the investigation.

[airhead10]

Architects, Engineers and Contractors have PI Insurance, (Professional Indemnity). Usually this is a statutory requirement built into their contract. this insurance will, (to certain limits) cover the cost of the damage arising from professional error/incompetence, however I can tell you from experience that the excess will likely be in the millions so whoever is ultimately found responsible will face a hefty bill.
Incidentally, it is the Architect, not the contractor, who is involved with the Olympic Stadium in Beijing.
Very tragic event, thoughts go out to all affected, some of them were from Hong Kong, so big news here.

[Notso Fantastic]

Looking at the pictures, some of the concrete pillars are still standing. The whole roof section appears to have come down in one piece. From what I could see, the roof section, in side profile fairly circular concrete, is attached on either side of the walkway at a point below the widest horizontal diameter. It appears to have 'slipped' off the walkway and come crashing down. The pillars look substantial- I think the failure was at the attachment between the roof and the walkway. or the joist along the walkway between the pillars. Someone certainly got their stressing horrendously wrong- without wind or snow it overstressed.

[max6462]

DXB

I flew to dubai about 3 weeks ago.
There is a long terminal in a sausage shape that looks very similar to 2E in Paris.
Was it similary designed?
They look alike to me , though I don t know much about architecture .

[411A]

Many years ago the old Kenelworth Hotel (Arthur Godfrey used to broadcast from here in the winter) in Miami was demolished, to make way for a newer structure.
Engineers got quite a surprise when they examined the concrete and steel used.
The rebar was far too small and beach sand was extensively used in the concrete mix.
One mentioned at the time that if a force 5 hurricane had happened by, the whole building would likely have collapsed like a house of cards.

Godfrey had quite a few exploits as a pilot, perhaps the most notable was his buzzing of the control tower, with his DC3, in New York. His flying license was suspended for six months after the incident, and when it was restored, he sold the DC3 and bought a Convair 340...later on a Gulfstream one, with what was absolutely new to private flying at the time...a Collins PVD.

[BahrainLad]

Originally Posted by max6462

I flew to dubai about 3 weeks ago.
There is a long terminal in a sausage shape that looks very similar to 2E in Paris.
Was it similary designed?
They look alike to me , though I don t know much about architecture .

They look similar, but Dubai is glass and steel whereas 2E used a lot more concrete. And I mean a lot more.....

[Lemurian]

Max6462,Bahrainlad,
Dubai airport and terminal 2E share the same design,the same architect (Andreu),the same design office (ADP).But not the same contractors -I think_.
In fact they're quite interchangeable.

[MarkD]

Obviously this is a tragedy for the families of those involved but the AP is reporting here that 2E represents 15pc of CDG capacity. Will CDG be able to accommodate all traffic in summer without 2E?

[pdalla]

Lemurian - FYI Dubai's terminal was built by Bechtel not ADP

[BahrainLad]

....that's what I thought, with ADP involved in the new, still under-construction, Terminal 3 and Concourse 2/3.

[Lemurian]

pdalla,
ADP 's role stops at the blue printing workshop.
The construction is the contractors'affair.
That's what I said.
P Andreu and the ADP design office have done the R&D work for more than 40 terminals worldwide.

[DeepC]

ADP 's role stops at the blue printing workshop.

Not if you have anything like CDM (Construction, Design and Management) regulations in France.

The designer has a duty of care to design for safe construction, use and maintenance of any structure he designs.

DeepC

[Lemurian]

Deep C,
Agree.
What I meant was that the design is ADP.the construction itself (the realisation) is awarded to contractors.
It didn't mean the designer had no responsibility whatsoever in the safety of the building,and I suspect a lot of questions are going to be asked about the design itself,the structure computations,the monitoring of the designers' specifications....the role of independant surveys during construction etc...etc.