Civil engineers believe it will cost more than $3 trillion to fix the nation's crumbling infrastructure. Elaine Quijano reports on how one group of engineers are working to ensure that bridges and other structures are ready for modern challenges.
See the CBS Report featuring Prof. Andrew Smyth, Director of Research, Adrian Brügger, Manager of the Carleton Lab, and Dr. Raimond Daddazio, CEO and President of Weidlinger Associates and alum of the Department of Civil Engineering and Engineering Mechanics.
An unusual test took place in Columbia Engineering’s Carleton Laboratory in mid-February: a simulated earthquake to see if a 2-½ ton, 10’ high pinnacle model from Washington National Cathedral could withstand the vibrations similar to the 5.8-magnitude tremor that struck the DC area in August 2011. The pinnacle was trucked up in pieces to the lab in the middle of snowstorms, reassembled by Cathedral stonemasons with a steel reinforcement rod inserted in the center, and then placed on the Lab’s shake table. The table is a custom-designed 5’ x 5’ piece of equipment that can shake up to a 3-ton payload with 3 g acceleration, three times the acceleration of gravity in the horizontal direction.
The “earthquake” was seconds away. The floodlights were on. The cameras and the sensors were ready. All eyes were on the two-ton section of a Washington National Cathedral pinnacle that stood like a missile in the Columbia University engineering laboratory. At 8 feet, it was the biggest object ever tested on the lab’s so-called shake table. (The table can hold 6,000 pounds.) The plan was to see if a steel reinforcing rod screwed through the middle would hold the limestone sections together.