Saturday, September 05, 2009

The Rebuilding of Ground Zero, Part 78

The Freedom Tower (1WTC) continues rising slowly from the surrounding work at Ground Zero. There are now three major cranes working at the site; two tower cranes that will be jacked up over time and eventually build out the tower, and a ground level heavy lift crane that is assisting the erection the heavy steel columns that will ring the exterior of the tower.

This view shows the already erected ground level exterior columns along the South side of the Freedom Tower. These massive beams are being connected to the core through a variety of heavy steel supports and stringers, which transfer the stresses and weight between the exterior columns and core. This view also shows the expansive street level platform that will eventually form the ground level 9/11 Memorial plaza. Concrete pours are taking place throughout the site.


This section of the tower hasn't gotten the massive steel beams yet, each of which is 60-70 feet tall and weigh 70 tons. However, you can see the complex form work and concrete pours necessary to transfer the weight from the tower down into the ground, which is 70-90 feet below the surface.

Close up of concrete pours that will form the ground level for the Memorial plaza

Diagonally across from the Freedom Tower, 4WTC is taking shape. Concrete pours and street level work is progressing. The sites directly to the North have finally been finished out so that Larry Silverstein can begin construction of 2WTC and 3WTC, although the completion date on those projects isn't assured because of financial and credit market constraints.


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