Architectural Skeletons Trivia Quiz

Answer: Wrought Iron

Cast Iron is brittle and fails went bent or stretched, but it works under compression. Wrought iron works under tension and compression. Steel, which is stronger, didn't become available as a building material until later.

Answer: Wrought Iron

Eiffel designed the wrought iron skeleton which is clad with copper per Bartholdi's design. Bartholdi's first idea was to make a hollow statue filled to the hips with sand. This wouldn't have worked since the outward thrust of the sand would have ripped the copper sheathing apart at the seams.

Answer: Cast Iron

Despite the exterior surface articulation and coffered interior which make the Capitol look like a classical masonry dome, the dome is made of cast iron ribs which are clad in cast iron sheets painted white. It is possible to use cast iron here since domes work in compression. If it were a tower, wrought iron would have had to have been used.

Answer: Steel

The steel structure is clad with granite, brick, and limestone. Incidentally, since this is steel and not iron, it is significantly taller than any wrought iron structure in the world.

Answer: Concrete

The Romans mastered concrete construction but thought it unsightly, so they often clad it in travertine or marble. After the fall of Rome, the art of concrete construction lay forgotten until just this century.

Answer: Stone

In this quiz so far, this and the Eiffel Tower are the only buildings where you can actually see what the structure is made of. The Washington Monument is actually made of stone all the way through. It was the tallest building in the world, but the limitations of stone as a structural material are evidenced by the fact that the Eiffel Tower almost doubled the monument's height only a few years later.

Answer: Prestressed Concrete

This is another example of the structural material being 'expressed'. The shells of the opera house would be extremely difficult to construct out of anything but concrete. They are very thin, so the concrete is 'prestressed' which means that the concrete is poured over tensed steel cables.

When the concrete cures, the cables impart a compressive load on the concrete. You have to be careful when transporting a prestressed concrete panel because if you turn it upside-down, the force from the cables would work downward instead of upward and the panel would crumble.

Answer: Marble

This is mind-blowing if you think about it. Usually a thin layer of marble is applied over a structure of brick or cheaper stone, even back then. This thing is pure white marble all the way through.

Answer: Concrete

The structure is a hybrid, but is primarily concrete. They used a high strength concrete that is three-times stonger than conventional concrete and much more effective than steel for sway reduction. The longest pour took 54 straight hours.

Answer: Concrete

Some theorize that this upside-down, truncated conical building is the most stable structure in all of New York City. This is the only building Frank Lloyd Wright designed in New York City.