HomeDiagramsDatabaseMapsForum About
     

Go Back   SkyscraperPage Forum > Discussion Forums > Buildings & Architecture


    Salesforce Tower in the SkyscraperPage Database

Building Data Page   • Comparison Diagram   • San Francisco Skyscraper Diagram

Map Location
San Francisco Projects & Construction Forum

Reply

 
Thread Tools Display Modes
     
     
  #581  
Old Posted Apr 21, 2014, 11:10 PM
tall/awkward tall/awkward is offline
Registered User
 
Join Date: Aug 2012
Posts: 175
True that, waka. A lot of people don't realize that the wings were not in Transamerica's original plan. Yet another design altered by non-designers' input...
Reply With Quote
     
     
  #582  
Old Posted Apr 23, 2014, 4:38 AM
minesweeper minesweeper is offline
Registered User
 
Join Date: Jul 2011
Location: San Francisco
Posts: 613
Looks like another big concrete pour tonight. As of 8pm:



And trucks are still lined up as of 9:30pm:

Reply With Quote
     
     
  #583  
Old Posted Apr 23, 2014, 4:44 AM
fflint's Avatar
fflint fflint is offline
Triptastic Gen X Snoozer
 
Join Date: Jul 2001
Location: San Francisco
Posts: 22,207
On a related note, since 2008 I've been riding my bike around the Port of SF between Islais Creek and Heron Head Point. Never have there been so many little mountians of materials used to make concrete for pours like this.
__________________
"You need both a public and a private position." --Hillary Clinton, speaking behind closed doors to the National Multi-Family Housing Council, 2013
Reply With Quote
     
     
  #584  
Old Posted Apr 23, 2014, 11:11 PM
brantw's Avatar
brantw brantw is offline
Get me out of here
 
Join Date: Sep 2009
Location: San Francisco, CA
Posts: 300
Quote:
Originally Posted by minesweeper View Post
Looks like another big concrete pour tonight. As of 8pm:

And trucks are still lined up as of 9:30pm:
Ok, looks like you are right!

Last edited by brantw; Apr 24, 2014 at 6:00 AM.
Reply With Quote
     
     
  #585  
Old Posted Apr 24, 2014, 12:13 AM
rocketman_95046's Avatar
rocketman_95046 rocketman_95046 is offline
Registered User
 
Join Date: Aug 2002
Location: SD/SJ, CA, USA
Posts: 1,879
Quote:
Originally Posted by brantw View Post
I don't think that was for the SalesForce Tower. I was by there earlier today, and it's still just a bunch of dirt. Perhaps it was for the terminal?

Why was this thread moved to the Construction forum? I thought there was supposed to be a set of rules before it was declared under construction.
This was definitely for Salesforce Tower you could watch.the pour on the webcam. These pours are for the caissons that are over 275FT deep. After the pours the are covered so that they can work on the next ones.

Simms photo documented this process a few pages back.
__________________
1,000 posts and still going...
Reply With Quote
     
     
  #586  
Old Posted Apr 24, 2014, 3:03 AM
Guiltyspark's Avatar
Guiltyspark Guiltyspark is offline
Registered User
 
Join Date: Aug 2011
Location: Metro Detroit
Posts: 937
Quote:
Originally Posted by brantw View Post
I don't think that was for the SalesForce Tower. I was by there earlier today, and it's still just a bunch of dirt. Perhaps it was for the terminal?

Why was this thread moved to the Construction forum? I thought there was supposed to be a set of rules before it was declared under construction.
There is. This meets them.
Reply With Quote
     
     
  #587  
Old Posted Apr 24, 2014, 3:50 AM
hruski hruski is offline
Registered User
 
Join Date: Aug 2010
Posts: 165
Quote:
Originally Posted by rocketman_95046 View Post
This was definitely for Salesforce Tower you could watch.the pour on the webcam. These pours are for the caissons that are over 275FT deep. After the pours the are covered so that they can work on the next ones.

Simms photo documented this process a few pages back.
Can someone explain to me why they don't dig out to the bottom level of the foundation/parking garage before digging/pouring caissons? Seems like pouring them out now will make excavation more difficult later.
Reply With Quote
     
     
  #588  
Old Posted Apr 24, 2014, 5:27 AM
rocketman_95046's Avatar
rocketman_95046 rocketman_95046 is offline
Registered User
 
Join Date: Aug 2002
Location: SD/SJ, CA, USA
Posts: 1,879
Quote:
Originally Posted by hruski View Post
Can someone explain to me why they don't dig out to the bottom level of the foundation/parking garage before digging/pouring caissons? Seems like pouring them out now will make excavation more difficult later.
I don't know for sure but this is not uncommon, just look across at 181 Fremont who is doing the same thing. We can guess.

1. It may be more operationally efficient to move the huge equipment around out of a confined hole.

2. Soil at that depth might not be stable enough for the caisson drill rigs.

3. They may need to wait until the terminal substructure next door is complete before excavating.

4. It might be cheaper to do it this way.

I'm sure others have guesses as well.
__________________
1,000 posts and still going...
Reply With Quote
     
     
  #589  
Old Posted Apr 24, 2014, 5:35 AM
WonderlandPark's Avatar
WonderlandPark WonderlandPark is offline
Pacific Wonderland
 
Join Date: Mar 2006
Location: Bi-Situational, Portland & L.A.
Posts: 4,129
seems like they are doing top down bottom up with this and 181.

this blog explains the technique. http://constructionduniya.blogspot.c...struction.html
__________________
"The large print giveth and the small print taketh away"

travel, architecture & photos of the textured world at http://www.pixelmap.com
Reply With Quote
     
     
  #590  
Old Posted Apr 24, 2014, 1:38 PM
shakman's Avatar
shakman shakman is offline
Chairman
 
Join Date: Jun 2002
Location: PRMD - People's Republic of Maryland
Posts: 2,667
Quote:
Originally Posted by WonderlandPark View Post
seems like they are doing top down bottom up with this and 181.

this blog explains the technique. http://constructionduniya.blogspot.c...struction.html
Thanks for posting this information. I learn something new everyday.
__________________
"I measure the value of life not by how much I have, instead by what I have done.

-sb
Reply With Quote
     
     
  #591  
Old Posted Apr 24, 2014, 5:47 PM
horatio_the_hermit's Avatar
horatio_the_hermit horatio_the_hermit is offline
Captain Your Captain
 
Join Date: Aug 2005
Location: San Francisco, CA
Posts: 984
Quote:
Originally Posted by WonderlandPark View Post
seems like they are doing top down bottom up with this and 181.

this blog explains the technique. http://constructionduniya.blogspot.c...struction.html
Wow. I had no idea this was a thing. I guess that means we'll start to see above-ground progress made sooner I'd thought.
__________________
The host with the most, you could say.
Reply With Quote
     
     
  #592  
Old Posted Apr 24, 2014, 10:36 PM
cv94117 cv94117 is offline
Registered User
 
Join Date: Mar 2013
Posts: 133
Quote:
Originally Posted by horatio_the_hermit View Post
Wow. I had no idea this was a thing. I guess that means we'll start to see above-ground progress made sooner I'd thought.
Except it's not true. I think it's funny how there's so much wild speculation without a lot of information on this site. I find this site useful for project news and pictures, but don't come here for technical information. Most of what I read here about engineering and construction methods is flat-out wrong. Drives me crazy. Usually I hold my tongue, but this time only...

This is bottom-up construction. The caissons are done first because it is not possible to excavate such a deep hole without them. The caissons hold back the soil outside of the building allowing the hole to be excavated. If the excavation is deep enough, and depending on the geotechnical conditions, even that might not be good enough - once you get down deep enough temporary bracing may need to be added to keep the caissons in place. You see that everywhere downtown - that's how they built the Millennium tower and 350 Mission across the street. It's also what you can see in the Transbay Terminal excavation.

Then once the hole is fully excavated and braced, the structure construction begins from the bottom up. The temporary bracing is removed as the structure rises from the bottom of the excavation. That's what is going on now in the Transbay Terminal excavation. I haven't been by in a while, but the concrete that is being poured started at the bottom and may even be rising to the surface at some parts of the excavation at this point. When all of the substructure is constructed and temporary bracing is removed, the superstructure will begin.

There is such a thing as top-down construction, but I'm not aware of any projects currently being built that way in SF (or even any in at least my recent memory). With top-down construction (at least one version of it), instead of putting in temporary bracing as the excavation proceeds, the permanent structure would be put in place moving downward. Depending on the details, this might also allow the structure above-grade (if there is one) to proceed simultaneously, saving time. Depending on the details, this can be much more technically challeging and expensive. The tradeoff is time. The decision on which way to go involves as always, technical feasibility and money.

Of course after that rant, I could be wrong and 181 Fremont and the Salesforce Tower might be being built top-down - I don't have any information - but I have never seen it in SF and don't see why the economics of these two sites would be so much different from all of the other projects surrounding it (unless the developers are worried about completing before the crash and are willing to spend the extra $).

And that's all I'll say about that.

Last edited by cv94117; Apr 24, 2014 at 10:50 PM.
Reply With Quote
     
     
  #593  
Old Posted Apr 25, 2014, 12:44 AM
brantw's Avatar
brantw brantw is offline
Get me out of here
 
Join Date: Sep 2009
Location: San Francisco, CA
Posts: 300
Passed by, today. This was all I could see:

Reply With Quote
     
     
  #594  
Old Posted Apr 25, 2014, 1:04 AM
rocketman_95046's Avatar
rocketman_95046 rocketman_95046 is offline
Registered User
 
Join Date: Aug 2002
Location: SD/SJ, CA, USA
Posts: 1,879
Quote:
Originally Posted by cv94117 View Post
Except it's not true. I think it's funny how there's so much wild speculation without a lot of information on this site. I find this site useful for project news and pictures, but don't come here for technical information. Most of what I read here about engineering and construction methods is flat-out wrong. Drives me crazy. Usually I hold my tongue, but this time only...

This is bottom-up construction. The caissons are done first because it is not possible to excavate such a deep hole without them. The caissons hold back the soil outside of the building allowing the hole to be excavated. If the excavation is deep enough, and depending on the geotechnical conditions, even that might not be good enough - once you get down deep enough temporary bracing may need to be added to keep the caissons in place. You see that everywhere downtown - that's how they built the Millennium tower and 350 Mission across the street. It's also what you can see in the Transbay Terminal excavation.

Then once the hole is fully excavated and braced, the structure construction begins from the bottom up. The temporary bracing is removed as the structure rises from the bottom of the excavation. That's what is going on now in the Transbay Terminal excavation. I haven't been by in a while, but the concrete that is being poured started at the bottom and may even be rising to the surface at some parts of the excavation at this point. When all of the substructure is constructed and temporary bracing is removed, the superstructure will begin.

There is such a thing as top-down construction, but I'm not aware of any projects currently being built that way in SF (or even any in at least my recent memory). With top-down construction (at least one version of it), instead of putting in temporary bracing as the excavation proceeds, the permanent structure would be put in place moving downward. Depending on the details, this might also allow the structure above-grade (if there is one) to proceed simultaneously, saving time. Depending on the details, this can be much more technically challeging and expensive. The tradeoff is time. The decision on which way to go involves as always, technical feasibility and money.

Of course after that rant, I could be wrong and 181 Fremont and the Salesforce Tower might be being built top-down - I don't have any information - but I have never seen it in SF and don't see why the economics of these two sites would be so much different from all of the other projects surrounding it (unless the developers are worried about completing before the crash and are willing to spend the extra $).

And that's all I'll say about that.
CV,

The caissons are not for shoring. They are used to transfer the structural loads down to bedrock. We know this due to the location the holes are being made, and past press releases.
__________________
1,000 posts and still going...
Reply With Quote
     
     
  #595  
Old Posted Apr 25, 2014, 1:34 AM
simms3_redux's Avatar
simms3_redux simms3_redux is offline
She needs her space
 
Join Date: Sep 2005
Location: San Francisco
Posts: 2,454
Everybody is actually right here, though.

CV said that it will be bottom up construction whereby a hole will be excavated deep enough to require lateral bracing, and that is true. rocketman and the rest of us have pointed out that what is being put in the ground now are caissons, not (or not just) soldier piles to keep the soil at bay for excavation. So structural is going in place before excavation will begin, however, each tower is likely to still be bottom up construction.

We have not really uncovered the true reason why they are putting in the bedrock caissons before excavating (which is different from 350 Mission catty corner where they excavated and then put in caissons when they bottomed out), however, it could have to do with the Transbay Center and timing of that project. Perhaps they cannot excavate yet until there is enough adjacent substructure for the TB Center so that side-bearing walls between the two projects don't collapse. Right now, lateral bracing for the TB Center is pushing against dirt at Salesforce Tower and 181 Fremont. But if those two towers dug out their holes, there would have to be some serious coordination for the bracing in all 3 adjacent holes.
Reply With Quote
     
     
  #596  
Old Posted Apr 25, 2014, 6:12 AM
WonderlandPark's Avatar
WonderlandPark WonderlandPark is offline
Pacific Wonderland
 
Join Date: Mar 2006
Location: Bi-Situational, Portland & L.A.
Posts: 4,129
there was a tower done here in LA last cycle done top down. The methodology was very much the same as 181 & salesforce. I could be totally wrong and this is a special case. I am, however, not totally in the dark on construction, however, I profess no special inside knowledge on Salesforce. But given the photos, that is why I posted the link to s topdown blog entry. I hope it was informative, and given that SF is a sizzling market now, top down can deliver the building quicker. Time and hopefully lots of pics will tell. Keep posting.
__________________
"The large print giveth and the small print taketh away"

travel, architecture & photos of the textured world at http://www.pixelmap.com
Reply With Quote
     
     
  #597  
Old Posted Apr 26, 2014, 5:24 AM
minesweeper minesweeper is offline
Registered User
 
Join Date: Jul 2011
Location: San Francisco
Posts: 613
From ground level, it looks like they're drilling for oil or something:

Reply With Quote
     
     
  #598  
Old Posted Apr 26, 2014, 10:36 PM
Surrealplaces's Avatar
Surrealplaces Surrealplaces is offline
Editor
 
Join Date: Feb 2006
Location: Cowtropolis
Posts: 19,968
I'm not a huge fan of the name, but the tower is still very nice and always will be. I wouldn't be surprised if the tower was renamed later anyway.

Quote:
Originally Posted by OhioGuy View Post
I agree. While I prefer the general name of Transbay Tower, the new name doesn't bother me at all.

(Though I'm still disappointed the USOC didn't relocate to Chicago several years ago. Apparently there were discussions about the USOC moving headquarters to the Sears Tower, which I hoped would mean renaming it the Olympic Tower... instead it's Willis Tower.)
Reply With Quote
     
     
  #599  
Old Posted Apr 26, 2014, 11:04 PM
biggerhigherfaster biggerhigherfaster is offline
Registered User
 
Join Date: Feb 2013
Posts: 111
In exchange for renaming, they should restore the originally planned (or at least considered) height of 1200 ft with 80 stories. Maybe Bienoff can pay a few hundred million dollars to fund the extension
Reply With Quote
     
     
  #600  
Old Posted Apr 27, 2014, 1:11 PM
Dale Dale is online now
Registered User
 
Join Date: Dec 2001
Location: Charlotte
Posts: 4,776
What about an 1,800' prefab tower and name it Tempforce Tower ? It could work.
Reply With Quote
     
     
This discussion thread continues

Use the page links to the lower-right to go to the next page for additional posts
 
 
Reply

Go Back   SkyscraperPage Forum > Discussion Forums > Buildings & Architecture
Forum Jump


Thread Tools
Display Modes

Forum Jump


All times are GMT. The time now is 10:04 PM.

     
SkyscraperPage.com - Archive - Privacy Statement - Top

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.