Coquitlam, B.C. shoring wall collapse. 8

[3DDave]

A fun shoring wall collapse.

https://bc.ctvnews.ca/jaw-dropping-video-shows-collapse-at-coquitlam-b-c-construction-site-1.6668311

Looks like the anchor team did a great job, the team who made the wall not such a great job, and whoever was in charge of deciding how many anchors to put in to go with that wall, a really terrible job.

It was slow enough in the early stages to get everyone away. So, expensive but not tragic. Except for the people managing the money. For them it's going to be rather painful. Also painful for commuters who used the street that no longer has dirt beneath it.

 

[MintJulep]

Video

https://globalnews.ca/news/10140550/video-collapse-coquitlam-construction-site/

 

[dik]

I'm glad there were no injuries... it appears there was a failure at the connection of the soil anchors to the wall.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[hokie66]

Looks to me like the 'wall' broke between the anchors. So maybe flexural capacity of the wall. Maybe too few anchors as well. Without any details, it is impossible to judge.

 

[Tomfh]

Yes it looks like it popped off the anchors. Punching shear style.

 

[MTNClimber]

It's tough to tell, but doesn’t look like there was much or any reinforcement in the shotcrete face. There should be mesh and waler bars to prevent the plates from punching and for the facing to span the distance between anchors.

 

[1503-44]

Yeah. Looks kind of like just a slurry wall there.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[MTNClimber]

Slurry walls are typically several feet thick and have reinforcement cages. This looks like a thin coating of unreinforced shotcrete. Maybe there is fiber reinforcement, but that's not enough in this application. Not sure who signed off on this but they need to be removed from the industry.

Thankfully, it appears everyone was removed from the excavation.

 

[Sym P. le]

Plenty of trench work in previous years. Collapse is at the let down for prior underground parking entrance.

Google Maps

 

[MTNClimber]

Street View not only picks up the shoring contractor's adverts on the fencing but there's also a different (possibly innocent) shotcrete company driving down the road next to the excavation with their logo on their truck. When advertising bites back.

 

[spsalso]

"Mistakes were made."

But who made them?



spsalso

 

[1503-44]

Yes, shot create is the better bet. It would be a very deep trench for a proper slurry wall.

Maybe the truck is advertising for the repair or additional work, except he didn't quite think it all the way through.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[dik]

ambulance chaser?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[1503-44]

The shotcrete company in Street view.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[MTNClimber]

Dik- this looks to be when the wall was in construction, so not an ambulance chaser.

 

[dik]

Thanks MTN... was just joking... I didn't know if the shotcrete truck was actually involved with the work.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[bridgebuster]

I saw this video on LinkedIn. The commentary was to the point "Holy F---"

Link

 

[spsalso]

A video commentary by Casey Jones:

https://www.youtube.com/watch?v=KHnvhlcLiUY

No surprises, including the city saying it might take months to figure out.

A guy did say that the city inspectors were overworked and departments understaffed. Might have been clever to charge a high enough permit fee to cover the cost of inspection. Did they give them a quantity discount?



spsalso

 

[MTNClimber]

I'm not sure why Casey Jones, with "experience in deep foundations," is shocked by a soil nail wall of this magnitude. How are you an "experienced professional engineer" in the geotechnical realm who has never seen a soil nail wall used on anything other than a "small slope"? I know deep foundations and retaining walls are two separate topics, but deep foundations are installed within deep excavations all of the time.

 

[phamENG]

I've yet to encounter an engineer making YouTube videos about anything more than high level concepts that I could get behind. All of the 'forensic videos' I've seen are pretty bad. A few engineering concepts mixed with wild speculation and occasionally ignorance or assumption that their viewpoint and experience is sufficient to make them an authority on the subject. The issue is that, once the facts are gathered, the public doesn't care anymore and you won't get the views and ad dollars. Better to rush out, say something (possibly wrong and dumb) to get the attention and then not retract it later because people wouldn't even know what you're talking about if you did.

YouTube is good for entertainment and how-to videos, less so for the news. The payment structure is not conducive to good journalism. Sensationalism reigns supreme.