99% Invisible - 99% Invisible-35- Elegy for WTC

Episode Date: September 2, 2011

I want to be careful not to overstate what it means for a building to die. A building’s worth is an infinitesimal fraction of the worth a person’s life. Even two buildings don’t even move the needle in comparison to … Continue reading →

We get support from UC Davis, a globally ranked university, working to solve the world's most pressing problems in food, energy, health, education, and the environment. UC Davis researchers collaborate and innovate in California and around the globe to find transformational solutions. It's all part of the university's mission to promote quality of life for all living things. Find out more at 21stCentry.ucdavis.edu. This is 99% invisible. I'm Roman Mars. I want to be careful not to overstate what it means for a building to die. A building's worth is an infinitesimal fraction of the worth of a person's life. Even two buildings don't even move the needle in comparison to real human loss.

But a building is still a living thing in a way. It breathes and it moves. This movement makes a sound. This structural engineer who designed the World Trade Center towers says that the people working inside couldn't feel this movement of the towers swaying in the breeze. But they could hear it. Often, buildings speak to you. Often, buildings speak to you. What happens in a tall building is that in the wind, as the building moves, the floor above moves with respect to the floor below. My full image is Leslie E. Robertson.

I'm a structural engineer and I was responsible for the design of the World Trade Center. This cassette tape was one of many that we took during the construction and later occupation of the building. For each cycle of oscillation of the building, you hear two creaking noises. And therefore, if you have a tape of it, you can then measure. Rather precisely, the frequency of oscillation the building itself. It takes 10 seconds for a world-trade center to go through one cycle of oscillation. This concludes the recording at the 67th Florida Tower A

projection rate. Yeah. I can't know what you're gonna say about it. I used to be extremely sound sleeper and the kind of put my head down the pillow and go to sleep and sleep for just a short while, get up and go back to work or do whatever. But it's kind of not like that anymore. I just... But I don't have images of the Trade Center in my dreams.

I do wake up with the thoughts in my head that I do, but it's sort of like instantaneous and then as you wipe your eyes, you wipe the thought out of your mind. People keep saying, well, you did everything you could have done, the design was the best it could be and you know all those thoughts, which are nice. But I guess ultimately the responsibility for the criteria for the Trade Center, that was my, those were my decisions.

And the fact that they stood up as long as they did was because we had designed the project for the impact of the 707 aircraft and we had a great team working on the project and they did what they were supposed to do. They stood up under the impact. And while it's true that the plane that hit it was a bit heavier and was flying a whole lot faster and therefore a whole lot more energy was put into the building. I think it's a tribute to the people who worked on the project that they did as well as they did. And yet I know, as well as I'm here right this moment, that the buildings could have been made more stoward, sure, they could have been made stronger, and they could have stood up longer.

And that was my decision. And that's, I think, in a sense I can't be faulted because the structures performed in many ways admirably. But there's always that nagging thought that maybe you should have done something else. And that I can't. I can't just push that out of my head. This episode of 99% Invisible was produced by the kitchen sisters, Davie Nelson and Nikki Silva and me Roman Mars.

It's comprised of extracts and outtakes from the Peabody Award-winning Sonic Memorial Project produced in 2002. A new 10th anniversary edition of the Sonic Memorial Project, which is narrated by my literary hero Paul Oster is going to be playing on public radio stations around the country, is very much worth your time to seek out. You can find out more at kitchensisters.org. This program, 9% of the symbol is made possible with support from Lunar, making a difference with creativity.

It's a project of KLW 91.7 local public radio in San Francisco, the American Institute of Architects in San Francisco, and the Center for Architecture and Design. Find out more at 99%invisible.org. you