The subway station at 72nd Street and Broadway is part of the original IRT line of 1904, and has a beautiful miniature head house as its original entrance. That entrance, along with the too-narrow platforms and way-too-narrow stairs meant that this station was crowded for decades. Around 2000, a plan was developed to slightly ease the overcrowding by building a new entrance (which opened in 2002) with new stairs half a block to the north, coupled with closing a couple of traffic lanes to extend Verdi Square. (I played a very small role in that project by designing bracing for the Verdi Monument to prevent damage from vibrations during excavation.)
The picture above is the interior of the new head house, which looks like a modern version of the old one. The outside of it is fine, although not as attractive as the old one. The inside…I have my doubts. You’re looking at three separate planes of glass in the picture: the glass above the fluorescent lights is a skylight, the glass directly below the lights is a clerestory around the base of the skylight, and the glass at the bottom of the picture is the east wall of the structure. All the glass, and the new brick as well, is supported by a steel frame.
The frame needs to be stable when subjected to wind load, but it’s a very small building and the forces aren’t that big. The decisions was made – somewhere, by somebody – to put diagonal-rod bracing in every clerestory panel. The round plate and the clevises were used to avoid the geometric interference where two bracing rods cross. This is all very exposed-and-honest structureish but it’s overkill. There are gusset plates welded at each vertical-to-horizontal connection that required more welding than creating moment connections would have. The amount of connection – gussets, clevises, the round plates – is far out of proportion to what it should be.
Simply put: the structure is unnecessarily complex as structure and not particularly attractive as architectural ornament. The way to have beautiful exposed structure is to have the structure make sense on its own terms.
