Cool timelapse video

BridgeTroll · July 25, 2009, 02:05:38 PM

The Manhattan Bridge...

http://www.liveleak.com/e/eab_1248485952

hooplady · July 25, 2009, 02:50:33 PM

Oh I wish I hadn't watched that! I never realized how much a large bridge flexes. I'm already askeered of the huge flyovers like the new one from I-95 to I-10.

Other than my new phobia, it was a cool post BT.

BridgeTroll · July 25, 2009, 03:20:14 PM

Sorry about that Hoop!

Charles Hunter · July 25, 2009, 03:27:16 PM

Cool. Does a rail transit line cross that bridge? Could that be the reason for the flexing?

aj_fresh · July 25, 2009, 04:06:56 PM

Yes, there are 4 sets of tracks. 2 on the south side, 2 on the north side.

http://en.wikipedia.org/wiki/Manhattan_Bridge#Subway_tracks

QuoteThe four subway tracks on the bridge are used by the New York City Subway. On the Manhattan side, the south side tracks, used by N Q trains, connect to Canal Street on the BMT Broadway Line while the north side tracks, used by the B D trains, connect to the Chrystie Street Connection through Grand Street. On the Brooklyn side, the two pairs merge under Flatbush Avenue to a large junction with the BMT Fourth Avenue Line and BMT Brighton Line at DeKalb Avenue. For 18 years, between 1986 and 2004, one set of tracks was closed to repair structural damage.

QuoteBecause tracks were on the outer part of the bridge, passing trains caused the bridge to tilt and sway. The wobble worsened as trains became longer and heavier. The New York City Department of Transportation failed to maintain the bridge properly, and the tracks finally were closed for repairs, blocking the paths of the trains that cross the bridge and reducing the number of trains passing between Manhattan and Brooklyn. The north tracks, which had been more heavily used, were closed first, from 1985 to 1988. The blockage split the B and D trains into two sections and rerouted the N via the Montague Street Tunnel. The south tracks were closed in December 1988, and except for a brief period in mid 1990, remained closed to trains until July 22, 2001, merging again the B and D trains and rerouting the Q to 6th Avenue. When the south side opened again, the north side was again closed, returning the Q to Broadway, introducing the new W line (which ran on the West End Line) and cutting B and D service from Brooklyn. On February 22, 2004, the north side reopened, and all four tracks were in service simultaneously for the first time in 18 years. B and D trains returned to Brooklyn on opposite routes (B to the Brighton Line, and D to the West End Line), the N once again uses the bridge for travel, and the W no longer runs in Brooklyn. Also, the north tracks were closed during off-peak hours between May and November 1995, and the same for the south tracks in 2003

reednavy · July 25, 2009, 04:29:32 PM

Quote from: hooplady on July 25, 2009, 02:50:33 PM
Oh I wish I hadn't watched that! I never realized how much a large bridge flexes. I'm already askeered of the huge flyovers like the new one from I-95 to I-10.

Other than my new phobia, it was a cool post BT.

If it didn't flex, it'd break.

BridgeTroll · July 25, 2009, 05:09:29 PM

Oh I know... that is part of the genius of the suspension bridge. It just happens so slowly we never actually see it.

hooplady · July 25, 2009, 05:12:39 PM

Geez, now I have to worry about it flexing...or NOT flexing!!!

Lunican · July 25, 2009, 05:37:17 PM

That's pretty cool. The flexing does look like it coincides with trains crossing the bridge.

aj_fresh · July 25, 2009, 06:17:53 PM

Yeah, it does. However, you don't feel it while you are on the train. The trains cross at a slow rate of speed.

This used to be my daily commute. I would love to take a train right about now.

Seraphs · July 28, 2009, 04:42:37 PM

Truly awesome! The flex is more dramatic than I would have thought.