Steel

Rivets in U.S. Structures

by Gabriel Pardo Redondo on December 8, 2017


(Picture: Three workers installing rivets in the construction of the Empire State Building in 1931, from the Lewis Hine collection at the NYPL.)

Rivets in the metal structures now seems archaic and from other times. However, rivets were extensively used for metal structure in the 19th century and in the first half of the 20th. The use of high-strength bolts displaced the rivets in the second half of the century and nowadays rivets are no longer in use.

In USA, and specially in New York, rivets were used until the 1960s even though high-strength bolts were already available. A proof of that is the original specifications of a 1961 building in the Flatiron District of New York on which I am currently working. The specification reads “All shop connections to be riveted or welded”. There is no mention about bolts, that gives a sense of how rooted rivets were into the common practice to erect structures.

For the ones that are not familiar with the arduous process of riveting here a short video of riveting in the Empire State Building. (The riveting process starts in the fourth minute.) As you can see it required a worker to heat the rivets (fires in construction sites are never a good idea), two workers to install them and most importantly a good catcher (see picture).

When Is An Arch Not An Arch?

November 15, 2017

That’s the F/G subway, paralleling 9th Street in Brooklyn, where the tracks cross over Fourth Avenue. The train is elevated here because it crosses over the Gowanus Canal a little to the west at the Smith/9th Street station. As the tracks head east, to the left, they stay at roughly the same elevation as the […]

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Changing Fashions

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The black paint and lighting make the picture a little hard to read, but this is an old gentleman dressed up in the latest fashion. The building is 2 Rector Street, now known as 101 Greenwich Street*, a 1905 office building that was expanded vertically in the 1920s. It’s a fairly typical building of its […]

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Different Types of Efficiency

October 19, 2017

I seem to keep coming back to train station roofs as I write. That’s happening partly because I travel by train a good amount so I’m looking at those roofs, and partly because they tend to have exposed structure designed by engineers with little or no separate architectural design, which may not make them beautiful […]

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Detailing For The Forces

October 17, 2017

A big part of structural design is “detailing,” which is drawing the way various pieces of a building  are connected. The bridge above (click to enlarge all of the photos) is in Wrocław and has a shorter span than the average American suspension bridge of any era. I walked over it a number of times […]

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Composite Structure

August 21, 2017

That’s the side wall and an oblique view of the front of a small building on Nassau Street. The front appears to be early twentieth century, but the odds are good that this is an older building that has been modified multiple times. If nothing else, the storefront – visible as sheet metal at the […]

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Sidewalk Vaults and True Obsolescence

August 14, 2017

For people unfamiliar with sidewalk vaults, the illustration above, from 1865, might seem plausible, but it’s actually Daniel Badger’s fantasy of how he could sell more iron. The left-hand side is reasonably accurate for mid-1800s vaults: the facade columns extend down past the plane of the sidewalk, marking the separation of the cellar proper from […]

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Weathering Metals

August 9, 2017

Beautiful, right? Thanks to some old alteration work, we get to see the results of a nice little experiment in exposing metals to water. You’re looking at three beams here: a modern steel beam that had been directly supporting a sidewalk (middle left, outlined in purple below), the original cast-iron girder that supports that beam […]

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Self-Contradictory Structural Decoration

August 1, 2017

I thought I was done looking at the Pearl Street bridge that is part of the Brooklyn Bridge approach, but apparently not. This is another view of the new steel of the arch structure that was installed to resupport the original truss bridge. The big beam at the bottom and the two diagonal braces above […]

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Decorating Structure

July 18, 2017

The picture above is an oblique view of the Pearl Street bridge in the Brooklyn Bridge approach, showing the original (1880s) truss above and the newer (probably 1950s) arch below. As previously mentioned, one of the notable differences between the two eras is the type of steel member used: eyebar chains for the bottom chord […]

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