I was watching TV in bed a few weeks ago and was about to turn in when PBS announced a Nova special: Engineering Ground Zero. The program was so interesting that I stayed up to watch it.
This program isn’t so much about what happened 9/11, 2001, it is about the rebuilding of this 16-acre site.
THAT WAS THEN…
The film is inspiring, hopeful, with leaders who are full of innovative ideas that will amaze you!
Yes, when they first began talking about rebuilding a skyscraper, I admit, I thought they had lost their minds! But after seeing this film, I feel very reassured and that is why I wanted to write this post, to share with you what I learned from this program.
There were many bitter disagreements, starts and stops in this rebuilding process, but when momentum took hold, Michael Arad was chosen as the architect and designer of the 9/11 Memorial. It was a design that was chosen out of 5,000 entries.
In no particular order, the film mainly covers:
The 9/11 Memorial (the cascading pools)
The MemorialPlaza (includes the 400 trees)
One WorldTradeCenter (the skyscraper)
The underground massive museum
The glass panels
The bronze panels
The 9/11 Memorial
The Memorial is a phenomenal structure of two flowing water pools where the twin towers had been. I get goose bumps when I think about it because water has so much significance when you think about it. To me it signifies cleansing, purity, sustenance, life, and healing properties. Each of these pools is 30,000 square feet, almost an acre of void. The design calls for 52,000 gallons of water to cascade over the walls every minute, drop 30 feet, and disappear into a second, inner pool. What Arad created was brilliant, genius!
The Bronze Panels
Names of the 2,982 individuals whose lives were lost are not listed alphabetically, but by the locations where individuals died: the South Tower, the North Tower, Flights 11, 93, 77, 175 and the Pentagon. First responders and those who died in the 1993 attacks are also grouped together. One-hundred-fifty-two bronze panels will surround the pools with these names.
For fifty percent of the people that are on the Memorial, no remains were found, so this is going to be, for many families and many loved ones, the place that they will go on those special days: the birthdays, anniversaries. Unfortunately, this is the final resting place of the deceased.
They wanted the memorial part of the site to be completed on the 10-year anniversary of the attack, September 11, 2011. They accomplished that goal and you get to see this beautiful memorial from start to finish in the film. When fully completed, the entire site will include a train station to rival Grand Central, six new towers, and, at its heart, the 9/11 Memorial.
One World Trade Center skyscraper begins with world-renowned architect David Childs who is striving for a balance of security with beauty. The first 20 stories are like a bunker, built to withstand the force of a truck bomb. As it rises, the tower transforms into eight interlocking triangles, covered in huge panels of clear glass. More than a hundred stories up, a broadcast antenna brings the total height to a symbolic 1776 feet. The cost? More than three billion dollars, Childs’ design will be one of the most expensive skyscrapers ever built and one of the most innovative.
The core of One World Trade Center contains critical safety systems like extra-wide stairwells. It’s made of a material that’s strong like steel, but more fire-resistant: concrete.
The cores in the Twin Towers were compromised on 9/11, because they were made of steel wrapped in thin sheetrock. Childs’ design calls for super-strong concrete. So strong that it had to be developed in the lab. In testing this new concrete, they formed a four-inch-diameter cylinder of the concrete. It can accommodate a thousand Americans standing on this one cylinder. Challenges are getting the concrete to the site before it hardens, not to mention pumping it up 40 stories high.
When finished, One World Trade Center will contain almost 500,000 tons of this material, much of it in its core, which has walls up to six feet thick. Inside, the core protects a total of 70 elevators, as well as the extra-wide stairwells that are pressurized to keep smoke out. Smoke is the real killer.
Childs has a vision of using prismatic glass at the podium to add to the beauty of the structure. Cutting grooves into glass this thick and this large has never been done before. The only way to do it is to build a new machine from scratch.
The Glass Panels
Each glass panel consists of laminated safety glass on the inside, an insulating air space, and another thick pane of glass on the outside, lined with an energy-saving coating. The coating lets sunshine in while reducing heat, resulting in cost savings in office lighting and air-conditioning.
Installing these panels is a painstaking task: they can weigh up to 5,000 pounds. There are around 13,000 panels. When this wall of glass is complete, it will wrap around the entire building from the 20th floor to the top. I don’t know about you, but that blows my mind!
The podium of One World Trade Center is a square about the size of the original towers. But as it rises above its base, at the 20th floor, the corners taper in. A square becomes an octagon. Four sides become eight interlocking triangles. Finally, at the top, it resolves in a square once again. Above the podium, One World Trade Center is going up a floor a week.
The “Green” Building
One World Trade Center is designed to be a certified green building. Steel contributes to that, because much of it comes from recycled materials like old refrigerators, cars, even toasters, all melted down into liquid.
Some of the largest steel pieces are called nodes. They can be as large as 60 tons and stand three stories high. Nodes are giant joints that hold multiple pieces of steel together. They come in all shapes and sizes and make it possible for the building to shift form, from four sides into eight. And they also help re-distribute the weight as the building rises.
THIS IS NOW…
Working with steel this big takes experience. Peter Jacobs is a member of the Mohawk Nation, famed for their work on skyscrapers and bridges for over a century. For more information about the Mohawk Nation, click here.
A massive underground museum is being built beneath the Memorial plaza. People are going to be looking up at the underside of the plaza above, which is 60-70 feet above. There will be a very large volume of space. People will understand the enormity, and the scale of what was lost.
Four hundred trees are being prepared to be taken to their new home: Ground Zero. They originally come from the three places where people died: New York, Pennsylvania and the Washington, D.C. area. These trees have their own computer chip in them. They have their own monitoring system for aeration and irrigation. Some weigh 18,000 pounds each.
The rebuilding of Ground Zero won’t be finished for years. David Childs’ original concept to cover the concrete podium with prismatic glass has been scrapped. Its replacement is yet undecided in this film. Many of this skyscraper’s safety features are likely to make it one of the most influential buildings in America.
By the way, you can watch the program online for free at: http://www.pbs.org/wgbh/nova/tech/engineering-ground-zero.html Just click on the green bar on the upper right. A DVD is also available for purchase.
Some films help us to move on from an uncomfortable place. This is one of those films.