world trade center getting buil

huangyhg

world trade center getting built
i guess i didn't know they had already started on the new world trade center tower (102 stories).  i thought they were all still squabbling over what the final design was and also not getting the money to rebuild it.
"thirteen shear walls had been poured as of last month, with the psi reaching 17,000 on several occasions."
what does the mix design for this strength look like?  i've workde with 10 to 12, but mever this high.
mike mccann
mmc engineering
msquared48, you can read of the properties of these concretes till ove 17000 psi in two leaflets (er, engineering bulletins) by pca
high-strength concrete
pca (portland cement association) 1994
engineering properties of commercially available high-strength concretes (including three-year data)
pca (portland cement association) 1994
the foundation for freedom tower has been going on for a few years. i think they added the columns so that the tourists think something's being built.
about two weeks ago the ny daily news reported there are still no tenant's and the project is slipping further behind schedule.
our office looks out over the site and i can tell you it's not much different than it was 6-months ago. what a disgrace.  
the aggregate for the concrete must be from a different location.  typically the maximum concrete strength in this region is 12 ksi.  i've heard of 18 ksi concrete being used in seattle.
i thought the whole thing was being held up because of the transit station that needs to go underneath it.
hg
the transit station is elsewhere in the site.
the problem is mainly competing interests, followed by lack of money and lack of tenants.
a few months ago it was reported in the media that the site might not be fully built out until ~2030.