Bible Exploration
Ever wonder why Roman buildings last so long while modern structures often degrade within a generation? A team of Utah University geologists has uncovered the secret behind the durability of structures made with Roman cement. The idea was actually suggested by the ancient writer Pliny the Elder.
In his first-century book, “Naturalis Historia,” Pliny described rock-like processes involving volcanic ash: “that as soon as it comes into contact with the waves of the sea and is submerged becomes a single stone mass, impregnable to the waves and every day stronger.”
After testing samples of Roman concrete, the archaeologists discovered the rare mineral aluminous tobermorite (Al-tobermorite) in the mortar’s composition. This was likely caused by saltwater and mineral interactions. What’s even more remarkable is the Roman engineers’ awareness of this concrete-stabilizing mineral.
Herod the Great (reign 37-4 BC) used this chemical reaction to build his famous harbor at Caesarea Maritima, the city he constructed on the Mediterranean coast and named after Emperor Augustus. The construction of the harbor’s breakwaters involved the use of “hydraulic concrete,” a mixture of mortar and volcanic sand imported from Italy.
The Romans transported thousands of tons of volcanic ash across the Mediterranean to construct harbors they knew would become lasting monuments of their engineering expertise.
Learn more about this incredible building process in ‘How Have Roman Structures Lasted So Long?’’