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SF Tower settlement Part III 18
- Thread starter dik
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I'm betting that Las Vegas has odds on this working, I know which side I would be betting on! When you start reading about what they plan on doing it just looks like they are looking for a cheap way out. On the 18 piles when they originally proposed 52? If I was a resident of the building I wouldn't want to be staying in it when they start during the excavation inside of the new shear wall they are going to install. We will all have to wait and see but....
There's a new element in one of the charts on the tip-o-meter. I'm talking about the one on page 4, otherwise called the yellow-and-grey page. If you examine the upper left, you'll see a large area that does not show any contour lines. It's about 30 x 50, if I've got my scaling right.
Now, one way to interpret this is that they're run out of numbers, so they can't draw the next line, and the succeeding ones. In that case, there may be a shipment of numbers coming in soon, so that the continually increasing tilt can be properly kept up with. It's unpleasant to run out of numbers, I can tell you!
Alternately, and I think I like this one better, is that that section of the slab has stopped sinking, and is staying at a flat plane. What's intriguing about this is that it would then hint that it might SNAP off. Won't THAT be fun?
Of course, there's also the version where some Big Guy said that if the building tilts more than 2.10 inches/units, that Heads Will Roll. Thus inspiring this hesitation to add those lines. Curiously similar to how it must feel to have to tell Putin that a few more square miles are, uh, missing in our inventory.
spsalso
Now, one way to interpret this is that they're run out of numbers, so they can't draw the next line, and the succeeding ones. In that case, there may be a shipment of numbers coming in soon, so that the continually increasing tilt can be properly kept up with. It's unpleasant to run out of numbers, I can tell you!
Alternately, and I think I like this one better, is that that section of the slab has stopped sinking, and is staying at a flat plane. What's intriguing about this is that it would then hint that it might SNAP off. Won't THAT be fun?
Of course, there's also the version where some Big Guy said that if the building tilts more than 2.10 inches/units, that Heads Will Roll. Thus inspiring this hesitation to add those lines. Curiously similar to how it must feel to have to tell Putin that a few more square miles are, uh, missing in our inventory.
spsalso
spsalso,
While it would be entertaining if the north-west corner of the mat has already broken off, I think that it is more likely that they just ran out of the ink that they used to draw the contour lines. [Or that the routine that draws the contours is still set at 2.1 inches max. If anyone from Slate follows this site, you need to re-set that limit.] The preceding figure shows 2.4 inches settlement for LE-01, which is close to the NW corner, so the contours should fill in nicely over to the corner. But many thanks for your naming and continued interest in the Tilt-O-Meter.
While I am at it, I am not entirely sure what is going on at present, but I think they have been installing, or trying to install, the jet grout plug down below 25 feet along the future Mission Street excavation. According to the single best boring log that I have seen, PB-1, which is around the corner on Fremont Street, there is young Bay Mud from 25 to 35 feet. Jet grouting is not very effective in young Bay Mud - see the reports and paper on what happened on the Posey Tube seismic "retrofit". [I put retrofit in quotes because thar whole exercise was stupid!] The EDRT seems to have some awareness of this because they pushed the design team into agreeing that they will use chemical grouting as necessary to ensure that the bottom of the excavation is sealed, but that is also a bit dicey. Anyway, if anyone is planning to sneak into the excavation at night, wear your gumboots!
While it would be entertaining if the north-west corner of the mat has already broken off, I think that it is more likely that they just ran out of the ink that they used to draw the contour lines. [Or that the routine that draws the contours is still set at 2.1 inches max. If anyone from Slate follows this site, you need to re-set that limit.] The preceding figure shows 2.4 inches settlement for LE-01, which is close to the NW corner, so the contours should fill in nicely over to the corner. But many thanks for your naming and continued interest in the Tilt-O-Meter.
While I am at it, I am not entirely sure what is going on at present, but I think they have been installing, or trying to install, the jet grout plug down below 25 feet along the future Mission Street excavation. According to the single best boring log that I have seen, PB-1, which is around the corner on Fremont Street, there is young Bay Mud from 25 to 35 feet. Jet grouting is not very effective in young Bay Mud - see the reports and paper on what happened on the Posey Tube seismic "retrofit". [I put retrofit in quotes because thar whole exercise was stupid!] The EDRT seems to have some awareness of this because they pushed the design team into agreeing that they will use chemical grouting as necessary to ensure that the bottom of the excavation is sealed, but that is also a bit dicey. Anyway, if anyone is planning to sneak into the excavation at night, wear your gumboots!
They are I think screwing around with the jet grout plug and maybe beginning excavation along Mission Street. NW corner continues to trend down. A couple of weeks it has kicked up, but mostly when it has really gone down the previous week. Who knows why?
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/raw/upload/v1666723779/tips/076-03B_tis442.docx[/url]
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/raw/upload/v1666723779/tips/076-03B_tis442.docx[/url]
I wonder if this will have any effect on the buildings tilt? It's the 1st earthquake I've seen information about in the bay area since the problem was noticed. 5.1 Quake in SF Bay Area
I don't know that an M=5.1 earthquake would have had any effect, but if you check the legend in the figure in the link in my previous post you will see that the jet grouting on Mission St is said to have ended and that completion of the shoring wall on Fremont St has commenced! This is very peculiar as the HOA had said that they were going to connect at least some of the new perimeter piles along Mission St before they went back to Fremont, where the lateral roof tilt is already very close to what the design team had said would be their limit for the year. Maybe there was a problem with the jet grouting (as I predicted) and they have gone back to Fremont St to keep the contractor busy while they figure out what to do. This likely explains the sudden drop of the NW corner 2 weeks ago.
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Just an anecdote: Four Seasons luxury condos in SoMa have few takers
It took Millennium Partners 10 years to get this project going. It includes The Mexican Museum of Art. Much of Mexican Museum’s pre-Hispanic collection insignificant or fake
Millennium Partners sold the unfinished project to Westbrook Partners. Westbrook Partners has done a number of very lucrative deals for Millennium properties. This time they got bitten, it appears.
Featured in today's DailyMail
It took Millennium Partners 10 years to get this project going. It includes The Mexican Museum of Art. Much of Mexican Museum’s pre-Hispanic collection insignificant or fake
Millennium Partners sold the unfinished project to Westbrook Partners. Westbrook Partners has done a number of very lucrative deals for Millennium properties. This time they got bitten, it appears.
Featured in today's DailyMail
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