That’s the SS J.H. Sheadle, as it appeared between 1906, when first put into service, and 1913. The Sheadle had (under several different names) a very long life as a bulk freight carrier on the Great Lakes, shuttling coal, ore, and grain back and forth between various US and Canadian cities along the lakes and the St. Lawrence River. After an accident in 1979, the ship was scrapped because repair would have cost more than the aging freighter was worth.
A lot of the photos I use in the blog were originally taken by the Detroit Publishing Company, which took scenic pictures nationwide, but occasionally focussed on a topic close to home. As far as I can tell, the company had 16 pictures taken of the Sheadle during its construction for no more meaningful reason than it was constructed in Ecorse, Michigan, about five miles from Detroit. For example, here’s a view of the hull before launch:
The image that really grabbed my attention was this view of the (as yet unused) cargo hold. The scale of the space is clear if you look at the ladders on the far wall.
The big built-up steel girders at the top are holding up the main deck, and join seamlessly with the ribs on the sides, which are partially hidden by the sides of the hold. (In other words, the ribs that frame out the hull are in-between the sides of the hold and the sides of the ship.) All perfectly logical and standard ship construction in 1906. But…imagine that instead of looking toward the bow of a ship from inside a cargo hold, you’re looking down a shaft for two or three elevators and seeing the girders that support the floors of the building. It wouldn’t be identical to this, but it would be pretty close.
The main loads on the structure of a ship’s hull are at right angles to the main axis of the hull: sagging (when the front and back of the hull are supported on waves and the middle is less-well supported because it’s over a trough), hogging (when the middle is supported on a wave and the front and back are not well supported), and wave pressure on the sides. There is axial compression along the hull, when the engines are pushing the ship forward and water resistance pushes back at the bow and along the sides. There can be axial tension, when the engines are first put into reverse. If you image the hull on end, as if it were a tall building, the first three are the equivalent of lateral wind load, the compression is the equivalent of gravity, and the possible tension is the equivalent of vertical forces that can occur in strong earthquakes. The analogy is not perfect: the lateral loads dominate in ship design and the axial loads are fairly small, while axial loads dominate for short buildings and are significant even in tall ones.
Engineers spent the last third of the 1800s learning how to design rigid wrought-iron and then steel frameworks capable of carrying and distributing load while maintaining their shape. This basic idea was used in truss bridges, in tall buildings, and in ships: the details differ because the loads and non-structural requirements differ, but the concept remains. So why shouldn’t the framing of the deck and hold resemble the framing of a skyscraper?
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