Montreal Precast Failure

[dik]

From Toronto Globe and Mail:

"Léa Guilbeault didn't have a chance. What began as a romantic birthday celebration ended in unimaginable horror for a Montreal couple as a slab of concrete came crashing down on them in a downtown restaurant.

Ms. Guilbeault and her husband, Hani Beitinjaneh, were dining at a sushi bar in the atrium of the Marriott Residence Inn on Thursday night when the slab fell 18 storeys, killing the 33-year-old woman and injuring Mr. Beitinjaneh.

“It hit the woman right on the head, and her head was smashed,” an emotional witness, Kali Subramanian, told Montreal CTV News.

Mr. Beitinjaneh, also 33, who suffered serious injuries to his hand, was in shock as he was transported to Montreal General Hospital."

From the attached photograph it appears that the failure occurred at the precast connection.

 

[MikeHalloran]

A link

http://www.canada.com/Coroner

engineers report site Montreal concrete death/1805232/story.



Mike Halloran
Pembroke Pines, FL, USA

 

[Ron]

Mike's link didn't work...try this one...

http://www.canada.com/Coroner+engineers+report+site+Montreal+concrete+death/1805232/story.html

 

[JAE]

dik, you didn't attach anything.

 

[dik]

There was little of engineering merit in the newsarticle... from the photograph, it looked like the connections had failed clean.

Dik

 

[JAE]

So with a facade that large, I'm sure they are now wondering how many more connections are failing.

 

[ChadV]

Sounds familiar...

http://toronto.ctv.ca/servlet/an/local/CTVNews/20070516/marble_slab_falls_070516?hub=TorontoHome

 

[Teguci]

Vibration testing should be performed on the balance of the facade prior to opening up the streets below. Any anomalies in the vibration may indicate a soon to fail connection.

 

[InDepth]

Teguci: How is vibration testing performed? Is there a possibility of damaging the connection while testing? Is there a standard for this test?

 

[EEJaime]

Does anyone know who's precast system was involved in these incidents? It would be good information to have when specifying this type of construction. Or good background when you are checking the "Hell No" box on the submittal stamp!

 

[SkiisAndBikes]

Several years ago as a junior engineer I worked in Montreal and a portion of my work included facade inspections, including several buildings in the downtown area near this building. About 3 months ago my family and I returned to Montreal for a few days vacation. Our hotel was across the road from the building in question and my wife and I tried, unsucessfully, to entice our young kids to go for sushi in the very restaurant where this accident occurred.

While this type of event seems relatively rare, the results can often be catastrophic. It makes me think about how important these types of inspections are, how I can improve any future inspections that I may be involved with and also about ways the inspection process could be improved, especially when dealing with multiple hidden anchorages.

With keen interest, I await the results of the report and recommendations related to this story.

 

[graybeach]

I also wonder how many other connections are failing, and not just in this building. How many other buildings with precast facades were built circa 1967?

 

[csd72]

This is a very typical problem with facades.

The building looks like it was put up in the 70s, if that was the case then it would have been there for approximately 30 years.

No facade will last forever when subjected to the shrink/swell of thermal movement. Even the best designed facade connections will jam up a little with age and therefore induce fatigue in their metal parts.

As all these connections are usually hidden away they are hard to find during a routine inspection.

I wonder if this will induce a requirement for mandatory facade inspections at certain intervals.

 

[JedClampett]

I still have notes from a seminar titled "Special Considerations in Design of Cladding Attachments" from an AISC Conference from 1982. I was surprised by the fairly light type hardware used. In addition, these type connections are sometimes installed by a trade not experienced in making heavy type connections (i.e. masons instead of ironworkers).
Anyway, this has been an issue for many, many years and there's no reason to expect it to go away soon.

 

[Teguci]

InDepth - I wasn't the engineer analyzing the vibration testing. However, they did give a presentation on the theory.

Apply a small load and "listen" to the facade panels reaction. If the recorded vibrations vary significantly from a secure panel, then further testing is required. I imagine this is a lot like a chain drag on a concrete surface.

Not sure about a standard or failure during testing.

 

[trainguy]

This happened just around the corner from where I work...

tg

 

[dik]

I know from earlier work that precast panels and connection design was optimised due to the large number of them in a building.

Dik

 

[hokie66]

Optimised, dik? Does that mean skinny? Borderline? Not robust?

 

[SlenderBeam]

I am surprised no one has commented on this yet, but note the location of the failure - the corner.

It'd be interesting to see what wind code requirements were around for tall buildings at the time.

Clearly, the corners will receive the higher wind load due to wind vortices. I don't think it's a coincidence - probably fatigue failure of some sort and obviously poor maintenance.

 

[Ron]

Unfortunately a recurring problem for both pre-cast panels and natural stone panels. I have evaluated at least 4 such failures in the past 20 years...two in Orlando, one in Miami, as well as a brick facade failure in Jacksonville. Corrosion played a part in 3 of the 4. The one in Miami was related to an adhesive failure of a marble accent strip, but that caused an inspection of the stone panels behind the accent strip and corrosion issues were found.

None of the ones I worked on caused injury, just property damage. That's fortunate. The one in Montreal is truly tragic.