Ancient Roman Concrete Is About to Revolutionize Modern Architecture
After 2,000 years, a long-lost secret behind the creation of one of the world’s most durable man-made creations ever—Roman concrete—has finally been discovered by an international team of scientists, and it may have a significant impact on how we build cities of the future.
As anyone who’s ever visited Italy knows, the ancient Romans were master engineers. Their roads, aqueducts, and temples are still holding up remarkably well despite coming under siege over the centuries by waves of sacking marauders, mobs of tourists, and the occasional earthquake. One such structure that has fascinated geologists and engineers throughout the ages is the Roman harbor. Over the past decade, researchers from Italy and the U.S. have analyzed 11 harbors in the Mediterranean basin where, in many cases, 2,000-year-old (and sometimes older) headwaters constructed out of Roman concrete stand perfectly intact despite constant pounding by the sea.
The most common blend of modern concrete, known as Portland cement, a formulation in use for nearly 200 years, can’t come close to matching that track record, says Marie Jackson, a research engineer at the University of California at Berkeley who was part of the Roman concrete research team. “The maritime environment, in particular, is not good for Portland concrete. In seawater, it has a service life of less than 50 years. After that, it begins to erode,” Jackson says.
The researchers now know why ancient Roman concrete is so superior. They extracted from the floor of Italy’s Pozzuoili Bay, in the northern tip of the Bay of Naples, a sample of concrete headwater that dates back to 37 B.C. and analyzed its mineral components at research labs in Europe and the U.S., including at Berkeley Lab’s Advanced Light Source. The analysis, the scientists believe, reveals the lost recipe of Roman concrete, and it also points to how much more stable and less environmentally damaging it is than today’s blend.................