CHICAGO | One Chicago | 971 FT & 574 FT | 78 & 49 FLOORS - Page 83

Fvn · #**1641** Posted **Jul 23, 2019, 7:36 PM**

Quote:

Originally Posted by harryc

July 22

Haven't seen these in other secant walls - look too big to be for conduit runs.

Chicago | One Chicago by Harry Carmichael, on Flickr

Crane Heds

Chicago | One Chicago by Harry Carmichael, on Flickr

Chicago | One Chicago by Harry Carmichael, on Flickr

Adding a junction box to a conatainer.

Chicago | One Chicago by Harry Carmichael, on Flickr

Chicago | One Chicago by Harry Carmichael, on Flickr

Adding Goop (anyone know what this is ?)

Chicago | One Chicago by Harry Carmichael, on Flickr

I wonder if they're adding tie downs/micropiles to the secant pile walls to add more strength so the walls can support more loads from the towers. That would explain the micro drill in pictures 5/6 too.

The goop is probably a polymer slurry

harryc · #**1642** Posted **Jul 23, 2019, 9:43 PM**

Quote:

Originally Posted by Fvn

I wonder if they're adding tie downs/micropiles to the secant pile walls to add more strength so the walls can support more loads from the towers. That would explain the micro drill in pictures 5/6 too.

The goop is probably a polymer slurry

I'll look more closely next week, but I haven't seen any micropile supplies or rigs since they reinforced the foundation for the dry-cleaners at the start of the project. [edit] the big green thing does look like it could be a big micropile rig - macro-pile ?

Polymer would fit since it produces water with the consistency of warm snot. What would be the benefit of using a polymer rather than the usual bentonite (clay) ? Or is this for something other than increasing the weight of the water ,heavier water = more pressure on the soil to keep the hole from collapsing before the caisson is pushed down.

bhawk66 · #**1643** Posted **Jul 23, 2019, 9:48 PM**

man, those are some big ass caissons.

Fvn · #**1644** Posted **Jul 23, 2019, 10:14 PM**

Quote:

Originally Posted by harryc

I'll look more closely next week, but I haven't seen any micropile supplies or rigs since they reinforced the foundation for the dry-cleaners at the start of the project. [edit] the big green thing does look like it could be a big micropile rig - macro-pile ?

Polymer would fit since it produces water with the consistency of warm snot. What would be the benefit of using a polymer rather than the usual bentonite (clay) ? Or is this for something other than increasing the weight of the water ,heavier water = more pressure on the soil to keep the hole from collapsing before the caisson is pushed down.

That rig (Casagrande C7) can be used for micro piles/tiebacks/jet grouting. So its most likely gonna be used for one of those 3 things.

I don't think they used micro piles to underpin the other building. I think those were either pin piles or helical piles.

I'm not 100% sure of the benefits of polymer vs bentonite but I think polymer slurry is denser so they need less of it overall? Also, I could be wrong but I think synthetic slurry doesn't mix with the drilling spoils (spoils just sink to the bottom and get removed via cleanout bucket) whereas bentonite gets mixed and needs to be separated before reuse

marothisu · #**1645** Posted **Jul 23, 2019, 11:51 PM**

Tower crane permit was issued yesterday for tower A

harryc · #**1646** Posted **Jul 24, 2019, 12:02 AM**

Quote:

Originally Posted by Fvn

That rig (Casagrande C7) can be used for micro piles/tiebacks/jet grouting. So its most likely gonna be used for one of those 3 things.

I don't think they used micro piles to underpin the other building. I think those were either pin piles or helical piles.

I'm not 100% sure of the benefits of polymer vs bentonite but I think polymer slurry is denser so they need less of it overall? Also, I could be wrong but I think synthetic slurry doesn't mix with the drilling spoils (spoils just sink to the bottom and get removed via cleanout bucket) whereas bentonite gets mixed and needs to be separated before reuse

Thank you !

Bombardier · #**1647** Posted **Jul 25, 2019, 12:54 AM**

Quote:

Originally Posted by Fvn

That rig (Casagrande C7) can be used for micro piles/tiebacks/jet grouting. So its most likely gonna be used for one of those 3 things.

I don't think they used micro piles to underpin the other building. I think those were either pin piles or helical piles.

I'm not 100% sure of the benefits of polymer vs bentonite but I think polymer slurry is denser so they need less of it overall? Also, I could be wrong but I think synthetic slurry doesn't mix with the drilling spoils (spoils just sink to the bottom and get removed via cleanout bucket) whereas bentonite gets mixed and needs to be separated before reuse

Correct, the polymer slurry holds back the earth below the temporary casing and still allows the rigs to clear the holes. This is typically for top of rock caissons. Some residual polymer slurry is disposed of with the spoils, which are mixed with dry spoils to get spoils that are dry enough for the dumps to accept them. The polymer slurry is pumped from a tank or an adjacent shaft with a full depth temporary casing (called a rat hole) into the hole being drilled. Then when the caisson is filled with concrete under the tremie method, the polymer slurry is pumped back into the rat hole until the next caisson is drilled. Once all caissons are complete, the add a chemical to dissipate the polymer and turn it back to normal water with a PH level that is acceptable to discharge.

harryc · #**1648** Posted **Jul 25, 2019, 3:22 AM**

Quote:

Originally Posted by Bombardier

Correct, the polymer slurry holds back the earth below the temporary casing and still allows the rigs to clear the holes. This is typically for top of rock caissons. Some residual polymer slurry is disposed of with the spoils, which are mixed with dry spoils to get spoils that are dry enough for the dumps to accept them. The polymer slurry is pumped from a tank or an adjacent shaft with a full depth temporary casing (called a rat hole) into the hole being drilled. Then when the caisson is filled with concrete under the tremie method, the polymer slurry is pumped back into the rat hole until the next caisson is drilled. Once all caissons are complete, the add a chemical to dissipate the polymer and turn it back to normal water with a PH level that is acceptable to discharge.

Cool stuff - now I know better what to look for. Rat Hole, Rat Trap, you'd think these guys are Union or something.

P1330100 by Harry Carmichael, on Flickr

LouisVanDerWright · #**1649** Posted **Jul 25, 2019, 1:12 PM**

^^^ The rathole is also useful for storing scabs...

rivernorthlurker · #**1650** Posted **Aug 4, 2019, 5:38 AM**

Was by the site today (Saturday). Looked like full crew drilling, pouring, etc. If they plan on working 6+ days a week + top down construction, hopefully this thing will fly.

LouisVanDerWright · #**1651** Posted **Aug 4, 2019, 2:38 PM**

When you review similarly sized developments in other US cities you realize we are really fortunate to get the design quality we do. This project is, for example, soooo much better than that 1000' Waldorf proposed for Miami that's a jumbled mess of stacked boxes. I'd rather have this any day that something awful like that which is 100' taller....

harryc · #**1652** Posted **Aug 6, 2019, 3:13 AM**

July 30

Chicago | One Chicago by Harry Carmichael, on Flickr

Aug 5

Chicago | One Chicago by Harry Carmichael, on Flickr

kolchak · #**1653** Posted **Aug 6, 2019, 3:22 AM**

Great update Harry. Thank you!

Is it so hot there that they are spraying the tires?

rivernorthlurker · #**1654** Posted **Aug 6, 2019, 4:14 AM**

Quote:

Originally Posted by harryc

July 30

Aug 5

Chicago | One Chicago by Harry Carmichael, on Flickr

Glad someone got a pic of this. This is the outside wall of Bella Luna Cafe. Sure it's been a pleasant place for a quiet lunch the past few days.

"Jim, do you hear something???"

harryc · #**1655** Posted **Aug 6, 2019, 10:04 AM**

Quote:

Originally Posted by rivernorthlurker

Glad someone got a pic of this. This is the outside wall of Bella Luna Cafe. Sure it's been a pleasant place for a quiet lunch the past few days.

"Jim, do you hear something???"

Better a secant wall than a pile driver ;-)

Quote:

Originally Posted by kolchak

Great update Harry. Thank you!

Is it so hot there that they are spraying the tires?

Cleaning them off to keep from tracking all the mud into the neighborhood. It was pretty dusty before they started this, there wasn't really space to do it along Chicago, but Dearborn is pretty wide here.

BonoboZill4 · #**1656** Posted **Aug 8, 2019, 4:59 AM**

Went up to this one for the first time, and damn... that site is insane! Not only has that area changed so much in the last 5 years, but this project alone is going to have as much of an impact as everything else built there in the last few years combined! Amazing, I recommend everyone spend a few minutes down there to observe if you can.

rivernorthlurker · #**1657** Posted **Aug 9, 2019, 3:08 AM**

Quote:

Originally Posted by BonoboZill4

Went up to this one for the first time, and damn... that site is insane! Not only has that area changed so much in the last 5 years, but this project alone is going to have as much of an impact as everything else built there in the last few years combined! Amazing, I recommend everyone spend a few minutes down there to observe if you can.

Totally agree with the characterization of the site. It feels like a "all hands on deck" effort and is impressive to behold. I mentioned before I was there on a Saturday and it was very busy.

glowrock · #**1658** Posted **Aug 9, 2019, 12:58 PM**

^^^

Absolutely. Was just in the area yesterday late morning and it was amazing to see how much activity is going on at one single site! One Chicago is going to have an enormous impact on the area, both from a street-level as well as skyline perspective. Can't wait to see vertical progress, perhaps by the beginning of the new year?

Aaron (Glowrock)

bhawk66 · #**1659** Posted **Aug 9, 2019, 3:19 PM**

Quote:

Originally Posted by BonoboZill4

Went up to this one for the first time, and damn... that site is insane! Not only has that area changed so much in the last 5 years, but this project alone is going to have as much of an impact as everything else built there in the last few years combined! Amazing, I recommend everyone spend a few minutes down there to observe if you can.

A bit off topic, but can anyone speak to the history of the "art deco" looking building on the right of this photo? Not very familiar with this one. Seems most taller buildings of this style were built closer to the CBD, no? Surprised to see one located there. Sticks out from all the modern high-rises around it. Very cool.

With OCS going up, this buildings value just went way up, imo. I could see it getting a clean up and up-lighting in a couple years and just shining like a gem to all the new activity across the street.

ChiPlanner · #**1660** Posted **Aug 9, 2019, 3:40 PM**

Quote:

Originally Posted by bhawk66

A bit off topic, but can anyone speak to the history of the "art deco" looking building on the right of this photo? Not very familiar with this one. Seems most taller buildings of this style were built closer to the CBD, no? Surprised to see one located there. Sticks out from all the modern high-rises around it. Very cool.

With OCS going up, this buildings value just went way up, imo. I could see it getting a clean up and up-lighting in a couple years and just shining like a gem to all the new activity across the street.

Old Lawson YMCA- was basically an SRO for the latter half of the 20th Century. Now it's "Lawson House," sold in 2014 under the agreement that it would remain as affordable housing. The developer proposed a full rehab in 2017 to turn the SRO units into full apartments- Though this has yet to happen.

Also- on the National Register of Historic Places.
https://www.nps.gov/nr/feature/place...G100000959.pdf