Penobscot Narrows Bridge

Infobox_Bridge
bridge_name = Penobscot Narrows Bridge

---

caption = The Penobscot Narrows Bridge with the Waldo-Hancock Bridge in the background
official_name = Penobscot Narrows Bridge and Observatory
carries = US 1 and ME 3
crosses = Penobscot River
locale = Prospect – Verona Island, Maine
maint = Maine Department of Transportation
id =
design = Cable-stayed bridge
mainspan = convert|1161|ft|m|0
length = convert|2120|ft|m|0
width =
height = convert|447|ft|m|0
clearance =
below = convert|135|ft|m|0
traffic =
open = December 30, 2006
closed =
toll =
map_cue =
map_

map_text =
map_width =
coordinates = coord|44.559|N|68.803|W |format=dms |region:US-ME_type:landmark |display=title,inline
lat=
long=

The Penobscot Narrows Bridge is a cable-stayed bridge over the Penobscot River near Bucksport, Maine. It replaces the Waldo-Hancock Bridge, built in 1931. The new bridge is convert|2120|ft|m|0 long. It is one of two bridges in the U.S. constructed recently to utilize a cradle system that carries the strands within the stays from bridge deck to bridge deck, as a continuous element, eliminating anchorages in the pylons. [The other of the first two bridges with a cable-stayed cradle system is the Veterans' Glass City Skyway. American Society of Civil Engineers, " [http://news.thomasnet.com/companystory/515472 Bridging To The Future Of Engineering] ", press release, March 12, 2007. Retrieved October 26, 2007.] Each epoxy-coated steel strand is carried inside the cradle in a one-inch steel tube. Each strand acts independently, allowing for removal, inspection and replacement of individual strands. The cable-stay system was designed with a system that uses pressurized nitrogen gas to defend against corrosion. Additionally, in June 2007, six reference strands within three stays were replaced with carbon fiber strands - a first in the U.S. Monitoring on the strands will evaluate this material for future use in bridge designs. These engineering innovations helped the bridge appear in the December 2006 edition of "Popular Science" as one of the 100 best innovations of the year. The total project cost was $85 million. The bridge was designed as an emergency replacement for the Waldo-Hancock Bridge and from conception to completion, just 42 months elapsed. A unique project delivery method, referred to as 'owner facilitated design/build' partnered Maine DOT with FIGG as the designer and Cianbro/Reed & Reed LLC as the contractor.

Observation Tower

The Penobscot Bridge site also is home to the Penobscot Narrows Observatory, the first bridge observation tower in the United States and the tallest public bridge observatory in the world. The tower reaches convert|420|ft|m|0 into the air and allows visitors to view the bridge, the nearby Fort Knox State Historic Site and the Penobscot River and Bay. The tower is accessible through the Fort Knox site and charges a $5 admission fee for adults.

The Penobscot Narrows Observatory opened to the general public on Saturday, May 19 2007 and remained open until October 31. In future years, it will be open at the same times of the year as Fort Knox (May 1 to October 31).

External links

* [http://www.maine.gov/observatory/ Penobscot Narrows Observatory "Official Site"]
* [http://fortknox.maineguide.com/ Admission information for the Observation Tower]
* [http://penobscotnarrowsbridgeandobservatory.info/ Information About Bridge and Observatory]
* [http://www.penobscotnarrowsbridgefest.com/ Penobscot Bridge Observation Tower]
* [http://www.explorenewengland.com/travel?article=/maine/articles/2006/10/08/view_from_a_bridge/ Boston Globe slideshow with audio on the project]
* [http://www.dywidag-systems.com/references/bridges/penobscot-narrows-bridge-maine-usa.html Information about cable staying tech used in this bridge]
* [http://www.penobscotnarrowsbridge.com/ Penobscot Narrows Bridge Community]
*Live [http://www.earthcam.com/client/mainedot/index.php WebCam] of the bridge.
* [http://www.michelestapleton.com/blog/2008/03/bravo-to-new-penobscot-narrows-bridge.html Penobscot Narrows Bridge and Observatory Pictures]

References

Gallery