[EarthResearcher333]

"A crack?"

Highlighted that long crack in the url FRpost below (see 2nd image in post) in blue. Also noted were the wide seams from "pull forces" in the wall and the spillway slab (highlighted blue). The wandering crack extends to just short of the wall. The angle is common to the under drain "herringbone" pattern cracking observed up & down the slabs in the mid-to-lower spillway.

Workers have sealed this long slab crack with Elastomeric sealant. The more interesting question is "what does the pull forces" seam widening in the wall and the adjacent spillway slab indicate? In the tilting scaffolding image it shows they have filled the main spillway slab notable "gap" with what looks to be a concrete patching compound. I suspect the scaffolding is intended for repair of the wall gap. The image reveals the width of this gap. This wall and slab section is just 1 up from the last collapsed slab & wall section of the blowout. For this size of a gap to appear -if neither present before the spillway failure- would indicate great forces could have been applied to the slab anchor bars and to the numerous & deep anchor rods of the spillway wall.

Engineers discussing a long crack in the Upper Main Spillway..

Scaffolding in preparing to fix seam gap in sidewall. Note the same width gap filled with grey patching compound in main slab seam in foreground.

[abb]

If that wall panel is close to the failure point, the gap could be from the entire spillway shifting downslope slightly, after losing the support of its adjoining panel.

[EternalHope]

Great pictures and analysis!

Look at the sealant they put on the bottom between the two slabs. It shows how wide the gap had grown. Some of the people in the picture are pointing at it.

It seems nearly inconceivable that the slabs could have pulled that far apart before this started. Even with the slipshod maintenance the spillway was getting in the past, something that large would have been cause for alarm. (At least common sense says it SHOULD have been. So maybe it wasn’t...)

So it seems likely the bottom slab has slid more than an inch downhill. That’s a LOT, and must have done a lot damage we can’t see. No way to fix that, and no way to strengthen it either.

It’s easy to see the whole slab going. They must be aware of that, they just don’t want to talk about it. I’d sure like to see a reporter ask about it in a news conference.

BTW: Your story about the forklift is hilarious. And the same type of flaw can appear in other things as well. Imagine the new hamburger flipper robots becoming unstable... :)

[WildHighlander57]

Thanks ER333 !

That gap filled with grey filler is —very— disconcerting..