Of all the innumerable positive attributes of concrete, durability is probably one of the most important. Durability implies not only long-term endurance but also the ability of concrete to resist weathering, chemical attack, abrasion and other natural and manmade conditions of service earthquakes, fire, flooding, extreme winds. Horace Greeley, famous editor of the New York Tribune, in a letter penned in 1860, made this comment: "I think concrete walls, rightly made, will last a thousand years." The key phrase rightly made.
The Romans, credited with the invention of concrete, recognized the value of the cementing action which pozzolanic tuff (a volcanic ash) and lime created when mixed together with water and stone fragments to produce concrete. Many examples of this construction remain today, attesting to the inherent durability of concrete construction. One magnificent example is the Pantheon in Rome. The 2000-year-old concrete dome, 142 feet in diameter and 71 feet high, is the largest dome ever built until modern times. The bronze rosettes and moldings have long since disappeared from the ceiling, and a stucco frieze was applied to the interior, beneath the dome, during the last Renaissance. Otherwise, the building exists entirely in its original form a unique testimonial to the durability of carefully formulated and placed concrete.
This article discusses the invention of Portland Cement; the nature of concrete; resistance to freezing, thawing, and chemical attack; abrasion and erosion resistance; protection against natural and man-caused disasters; resistance to low temperatures; and resistance to nuclear radiation.