Valley Line LRT | ?m | ?s | City of Edmonton

cliffapotamus

Active Member
Member Bio
Joined
May 10, 2020
Messages
421
Reaction score
2,628
I was biking by there tonight and i got up close to the piers in question. The wrap wasn't up all the way on the scaffold yet, so I was able to see the piers and a bit of the setup going on inside. On the 3 piers that are getting the scaffold, there appears to be an issue with moisture ingress into the concrete. The concrete, or at least the outer layer, is responding poorly to the recent rains we've had, and there is more dark staining than on the 'normal' piers, as well as a noticeable superficial cracking/crazing pattern. This pattern looks to be superficial, the kind of random lines one sees sometimes in concrete patches done with lightweight cement or in stucco scratchcoats. the cracks are all very small, revealed mostly by the excess moisture in the, as opposed to the dry areas around them. it's like a mess of wet cracks in dry cement.
I'm not super knowledgeable on the mechanics of concrete, especially stuff that's intended to be weather-exposed like this, but it looks to me like whatever finish layer got applied to the three piers getting scaffolded was too porous or otherwise not prepared properly, and is now aging rapidly due to moisture exposure. Like I said, it looks like the same cracking you see in porous/lightweight cement fills and patches in sidewalks and the like; and if I understand correctly, these piers were cast and then surfaced with a finish 'layer' or 'coat' of cement to give a consistent look.
This is all just my theory based on what I saw tonight. I don't know enough about concrete finishing to know for certain. as for how this affects opening; IDK. The issue can't be structural, that would have been picked up by now, especially given the viaduct segments the piers support have already been replaced, and I'm sure things were re-checked when that happened. There was a small electrical box and some wire hanging on one pier; I didn't think much of it and it wasn't labelled. any guesses?
Assuming the cast-in-place cores of the piers are structurally sound, and it's just a surfacing issue that can be resolved entirely from beneath the tracks, I'm betting the line opening shouldn't be delayed by this issue. That is assuming that there's nothing else wrong here, of course. hoping ofr hte best!
Anyways, here's a couple pictures I got using my bike light as a flash. the first two are of the scaffolded piers, the last is a photo of a normal pier to compare, given the bad camerawork. This stuff is a lot more visible in person.
unnamed-1.jpgunnamed.jpgunnamed.jpg
 

Attachments

  • unnamed-1.jpg
    unnamed-1.jpg
    113.6 KB · Views: 138

Gronk!

Senior Member
Member Bio
Joined
Aug 5, 2021
Messages
2,762
Reaction score
12,245
I'm guessing three things:
1) A Sept 4 go-live of the LRT line may not be likely unless TransEd invests some serious manpower and overtime on rectifying this issue
2) There will be second thoughts about above-grade LRT (favored by Vinesh Pratap) vs ground-level LRT
3) Above-grade LRT is another master stroke of competency by TransEd
 

Yossarian

New Member
Member Bio
Joined
Oct 1, 2020
Messages
51
Reaction score
341
I'm guessing three things:
1) A Sept 4 go-live of the LRT line may not be likely unless TransEd invests some serious manpower and overtime on rectifying this issue
2) There will be second thoughts about above-grade LRT (favored by Vinesh Pratap) vs ground-level LRT
3) Above-grade LRT is another master stroke of competency by TransEd
For #1, manpower will likely not be the limiting factor, rather the cure time for whatever repairs are needed, assuming they are structural. and not aesthetic issues.

My wife and I did 3/4 days of folk fest as park and ride, and each day on the bus in we saw the train parked at Muttart station, mocking us. If the Valley Line was open it would have been faster and cheaper for us to use that to get to and from the festival.
 

awstott

New Member
Member Bio
Joined
Jan 2, 2022
Messages
69
Reaction score
249
I would think if they are going for a Sept 4 opening they would be hyping it up big time. The fact it's been radio silence to me is indicative of another missed opening date. Mind you it is Transed and logic and common sense don't seem to apply to that group so maybe I'm wrong.
 

EdwardEdm

Active Member
Member Bio
Joined
Oct 22, 2021
Messages
123
Reaction score
390
I wonder if there's a way to add additional bracing to the supports.
Depends what the problem is, and I don't think anyone here knows enough to even speculate what might be a fix or not. Besides, bracing onto a cracked concrete surface sounds like a recipe for more cracking and won't so much if the pier has any major issues
 

northlands

Senior Member
Member Bio
Joined
Jun 18, 2019
Messages
1,095
Reaction score
4,482
Location
Grandin
was back in that area today so i looked again in the sunlight. I retract my optimism. The little box has sensors wired into it, the sensors are over a couple of the cracks showing near stress points on the pier. This is not good.
View attachment 418581
oy vey
 

Top