Project Leader:
Dr. Won-Young Kim
Earth Institute Contact: Dr. Won-Young Kim
EI Collaborators:
Mikhail Kogan
Locations: United States of America
Special Locations:
New York City
Description:
This project monitors the motions of the suspended spans and towers of the Verrazano Narrows bridge under ambient excitation as well as during the 2004 NYC marathon. The acceleration measurements under ambient conditions will aim to identify frequencies and shapes of the most prominent modes - vertical, torsional and lateral. Some rough estimate of modal damping may also be obtained from the spectral analysis.
There will be five principal tasks and one proposed optional task: the first is a preliminary monitoring to identify prominent frequencies and modes to assist in the deployment selection for the more complete survey; in the second task, over a period of approximately three days, periodic monitoring will be conducted at a minimum often locations, the third task will extract frequencies and mode shapes from the recorded data; the fourth will monitor motions at up to ten locations during the running of the NYC marathon when the runners will also be videotaped to correlate with observed bridge motions; task 5 will report the results of the testing and analysis; and, a sixth optional but strongly recommended task is proposed to monitor bridge deflections during the marathon using GPS technology.
EI Unit:
Lamont-Doherty Earth Observatory (LDEO)
Core Disciplines:
Earth Sciences
Collaborating Institutions:
Dept. of Civil Engineering
Funding Agency:
Parsons, Brinckerhoff, Quade & Douglas, Inc.