Suspension Span
The eastern segment connecting the Wards Island viaduct with Astoria, Queens was envisioned by original designer Arthur I. Perry as a dual-deck, 16-lane roadway supported by four suspension cables. When Amman came on board, he scaled back the design to a single eight-lane, truss-stiffened deck with two 3,104-foot long suspension cables hanging from two 315-foot-tall, 5,500-ton steel towers. Amman's modifications permitted use of foundations that had been constructed in the initial phase of construction while shaving $10 million off the budget.
The 1,380-foot main span hangs 135-feet over mean high water. The two 20-inch diameter cables each contain 37 strands, with each strand composed of 248 galvanized steel wires around 1/5th of an inch thick. The structure is unique in that the cables bend an unusually high 45 degrees at the anchorage bent posts, placing more of the load downward on the anchorages than is customary. The 20-foot-deep stiffening trusses surround the roadway on the main deck and obscure motorist views of the river and city, but the pedestrian walkway hangs over the river from the top outer edge of the truss, providing both exceptional views of the river and comforting separation from the traffic whizzing by below.
Lamp posts and other ornamental features (such as the tiered tips of the towers) reflect the Art Deco aesthetic of the 1930s. The four vertical posts between the legs of each tower are ornamental and have no structural purpose. When I visited in 2008, the bridge was undergoing a much needed dehumidification and renovation of the anchorages and a reanchoring of the cable strands.
Suspension span view from the South
Flagpole on the east approach in Astoria
Flagpole on the east approach in Astoria
Flagpole on the east approach in Astoria
Flagpole on the east approach in Astoria
Flagpole on the east approach in Astoria
Flagpole on the east approach in Astoria
Aluminum bas relief map in Astoria of the Triboro Bridge
East approach pedistrian walkway to Wards Island
Astoria just north of east approach
Lamp post on east approach
Temporary walkway hanging of north side of eastern anchorage
Temporary walkway hanging of north side of eastern anchorage
Concrete repair on eastern anchorage
Northeast cable anchorage eyebar
Repair of eastern anchorage
Pedstrian walkway and eastern tower
Eastern tower
Northeast joint of main span and east pier
Lamp
East tower
Hell Gate rail bridge viewed from the Triboro Bridge at sunset
Astoria Park viewed from the Triboro Bridge
Main span roadway viewed from the east
East tower viewed from the west
Hell Gate rail bridge
Anemometer on weather station
Ward's Island construction
West tower viewed from the east at sunset
Suspender cable attachment to main span
Lighting angle scale
Old unused sign display?
Northwest eyebar
Suspender cable
Joint
Air duct in tower
West tower viewed from the west
West tower and roadway coming off main span
Pedestrian walkway at west pier - note degraded concrete waiting to be replaced
Pedestrian walkway at west pier
Northwest cable
North pedestrian walkway, west tower
Renovated pedestrian walkway down to Wards Island with enclosed cage to prevent jumping or dropping of projectiles
Pedestrian walkway down to Wards Island
Construction equipment under Wards Island viaduct
West approach to the suspension span with walkway down to Wards Island
Pre-cast roadbed sections awaiting installation
Pre-cast roadbed sections
Pre-cast roadbed sections
Night view from the Northeast in Astoria Park
East approach by night
East approach by night