|Pantheon - Rome|
One of the most remarkable man-made structures I have ever visited is the Pantheon in Rome, once a pagan temple and now both a Catholic church and one of Rome's major tourist attractions. When one considers that the Pantheon was originally built in the first century, rebuilt in the second century, and still stands today as an intact and usable building, one's appreciation of the capabilities of Roman architecture and engineering soars. I realize the pyramids of Egypt are thousands of years older, but they are, in some respects, rather primitive structures built to impress the world (and presumably the gods) by their size. The pyramids are magnificent, but they lack the remarkable blending of art and architecture that results in a beautiful building fit for daily use, a building like the Pantheon.
|Pantheon Interior - Rome|
I can't imagine many structures being built today lasting more than a few hundred years. Indeed, I suspect the design and construction of most buildings these days include some consideration of planned obsolescence. Today's structures are also completely dependent on their internal systems, the infrastructure that enables them to function as usable buildings. Without its electrical, climate control, plumbing, and communications systems, without its elevators and fire-prevention systems, no modern skyscraper would be even inhabitable.
|The Pantheon's dome and oculus|
We can be thankful that the ancients didn't think the same way. If they had, ancient structures like the Pantheon would not be standing today. When they built something special they didn't consider such concepts as mean-time-between-failure or maintainability or six-sigma quality standards. But they built these structures to last. The walls of the Pantheon's dome, for example, are 20 feet thick at the base and only five feet thick at the oculus or eye at the top of the dome. The Roman engineers cleverly embedded lighter materials in the upper sections of the dome to reduce weight, and used the multi-row arrangement of waffle-like coffers for the same purpose. Until the 19th century no dome was larger, and the Pantheon's dome still remains the world's largest unreinforced concrete dome.
Interestingly, modern cement and concrete mixtures are much stronger than those used by the Romans, and are also reinforced with rebar steel. I wonder how many structures using these modern materials will still be around in the year 4100.
These odd thoughts were precipitated by an article addressing the latest findings on the construction of the Vatican's Basilica of St. Peter. Using specially designed radar, Vatican researchers discovered that the dome of St. Peter's was constructed using seven iron rings designed to reinforce the dome's travertine stone. And so, what we have is the totally unexpected use of a kind of reinforced concrete during the 16th century. This was apparently quite a surprise since the original construction details had long since been lost.
I'm always surprised by those who think we are so much smarter than those who went before us. Our predecessors might not have had access to our technology, but they certainly made better use of the technology they had. We do indeed stand on the shoulders of giants.
To read more about the engineering investigation of St. Peter's dome, click here.