A Friend of mine who lives in NYC sent me a link to the 12.24.15 New York Times article reporting on the continuing closure of the Ted Zoli designed/engineered pedestrian bridge in Squibb Park, Brooklyn, New York City [1]. Reporter Lisa W. Foderaro [2] explains that the bridge was constructed and opened in 2013, the bridge was closed without explanation in 2014, and remained closed in 2015.
No one will say why the bridge is closed. No one is talking. Too embarrassing.
When the bridge was opened Mr. Zoli explained that his design inspiration was the “trail” style suspension bridge.
You know, something similar to the catenary [3] cable, end anchored, pure suspension bridge that is used all around the world.
But Mr. Zoli’s bridge is different from a “trail” bridge because the Squibb bridge has a compressive deck and is not end-anchored in tension.
Mr. Zoli said the Squibb Bridge was meant to bounce and rock – for fun. You can see lateral deck bending in the image below. Note also that right hand side of walkway is lower (10"?) than the left side of the walkway. Not good. The walkway deck is in the process of overturning.
In the image below chair binders or come-a-longs are visible on the deck - used in post-slosure effort to "straighten" the deck. Image from NYTimes.
Think about it, if a bridge moves, there will be wear and tear. If there is wear, the bridge dimensions will change asymmetrically. So, intentionally designing a bridge that bounces and rocks is like designing a car with steering that doesn’t go straight – for “fun”! The Tacoma Narrows Bridge swayed and moved too – collapsing in a catastrophic wind powered harmonic . [6]
The ends of the Squibb bridge are not anchored in tension to the concrete tree-like towers. This is obvious because:
1. The bridge sections are not in alignment but zig zag – so no tension or compression can be transferred between the (2) independent deck “suspension” sections. 
2. “tree” like towers are not sufficiently rigid or massive to act as gravity anchors – compare to cable anchorages of the Golden Gate Bridge [7]
Instead the tension cables at the bottom of the Squibb bridge are put into tension by compression on the flat deck. But the deck is not a monolithic compressive element but rather a sectional compressive element. The bridge sections between the tree towers are trusses – with a lower tension chord and an upper compressive chord.
Who will say it? The Squibb Bridge design is flawed, The bridge needs to be removed.
| Attachment | Size |
|---|---|
| Frist_travertina_bridge_Jurg_Consett.JPG [9] | 68.43 KB |
| Squibb_bridge_image_underside_of_anchorage_from_max-carr_blogspot.JPG [10] | 40.72 KB |
| Squibb_bridge_image_from_brooklyn_heights_blog.JPG [11] | 60.56 KB |
| Trift_suspension_pedestrian_bridge_in_Alps.JPG [12] | 62.01 KB |
| Squibb_bridge_image_showing_lateral_deck_deflection_from_brooklyn_daily_eagle.JPG [13] | 56.87 KB |
| Not_Squibb_bridge_but_compression_truss_correctly_suspended.JPG [14] | 42.6 KB |
| Zoli_cv_and_Squibb_Bridge.JPG [15] | 72.52 KB |
| Squibb_Zoli_testing_chains_and_come_a_longs_on_the_decks_of_suspension_bridge.JPG [16] | 109.54 KB |
| Zoll_Squibb_Bridge_attempt_to_straighten_with_chain_rachets.JPG [17] | 139.21 KB |
