Augustus Caesar in 27 B.C. and lasting in Western Europe for 500 years, reorganized for world politics and economics. Almost the entirety of the civilized world became a single centralized state. In place of Greek democracy, piety, and independence came Roman authoritarianism and practicality. Vast prosperity resulted. Europe and the Mediterranean bloomed with trading cities ten times the size of their predecessors with public amenities previously unheard of courts, theaters, circuses, and public baths. And these were now large permanent masonry buildings as were the habitations, tall apartment houses covering whole city blocks.
This architectural revolution brought about by the Romans required two innovations: the invention of a new building method called concrete vaulting and the organization of labor and capital on a large scale so that huge projects could be executed quickly after the plans of a single master architect. Roman concrete was a fluid mixture of lime and small stones poured into the hollow centers of walls faced with brick or stone and over curved wooden molds, or forms, to span spaces as vaults. The Mediterranean is an active volcanic region, and a spongy, light, tightly adhering stone called pozzolana was used to produce a concrete that was both light and extremely strong. The Romans had developed potsalana concrete about 100 B.C. but at first used it only for terrace walls and foundations. It apparently was emperor Nero who first used the material on a grand scale to rebuild a region of the city of Rome around his palace, the expansive Domus Aurea, after the great fire of AD 64 which he said to have set.
Here broad streets, regular blocks of masonry apartment houses, and continuous colonnaded porticoes were erected according to a single plan and partially at state expense. The Domus Aurea itself was a labyrinth of concrete vaulted rooms, many in complex geometric forms. An extensive garden with a lake and forest spread around it. The architect Severus seems to have been in charge of this great project. Emperors and emperors’ architects succeeding Nero and Severus continued and expanded their work of rebuilding and regularizing Rome. Vespasian (emperor AD 63-79) began the Colosseum.
Which I have a model bad of. Built by prisoners from the Jewish wars the 50,000 Colosseum is one of the most intresting architectural feets of Rome. At its opening in 80 A.D. the Colosseum was flooded by diverting the Tiber river about 10 kilometers to renact a naval battel with over 3,000 participants. Domitian (81-96) rebuilt the Palatine Hill as a huge palace of vaulted concrete designed by his architect Rabirius. Trajan (97-117) erected the expansive forum that bears his name (designed by his architect Apollodorus) and a huge public bath. Hadrian (117-138) who served as his own architect, built the Pantheon as well as a villa the size of a small city for himself at Tivoli.
Later Caracalla (211-217) and Diocletian (284-305) erected two mammoth baths that bear their names, and Maxentius (306-312) built a huge vaulted basilica, now called the Basilica of Constantine. The Baths of Caracalla have long been accepted as a summation of Roman culture and engineering. It is a vast building, 360 by 702 feet (110 by 214 meters), set in 50 acres (20 hectares) of gardens. It was one of a dozen establishments of similar size in ancient Rome devoted to recreation and bathing. There were a 60- by 120-foot (18- by 36-meter) swimming pool, hot and cold baths, gymnasia, a library, and game rooms. These rooms were of various geometric shapes. The walls were thick, with recesses, corridors, and staircases cut into them. The building was entirely constructed of concrete with barrel, groined, and domical vaults spanning as far as 60 feet (18 meters) in many places.
Inside, all the walls were covered with thin slabs of colored marble or with painted stucco. The decorative forms of this coating were derived from Greek The rebuilding of Rome set a pattern copied all over the empire. Nearby, the ruins of Ostia, Rome’s port (principally constructed in the 2nd and 3rd centuries AD), reflect that model. Farther away it reappears at Trier in northwestern Germany, at Autun in central France, at Antioch in Syria, and at Timgad and Leptis Magna in North Africa. When political disintegration and barbarian invasions disrupted the western part of the Roman Empire in the 4th century AD, new cities were founded and built in concrete during short construction campaigns: Ravenna, the capital of the Western Empire from 492-539, and Constantinople in Turkey, where the seat of the empire was moved by Constantine in 330 and which continued thereafter to be the capital of the Eastern, or Byzantine, Empire. Christian Rome. One important thing had changed by the time of the founding of Ravenna and Constantinople; after 313 this was the Christian Roman Empire.
The principal challenge to the imperial architects was now the construction of churches. These churches were large vaulted enclosures of interior space, unlike the temples of the Greeks and the pagan Romans that were mere statue-chambers set in open precincts. The earliest imperial churches in Rome, like the first church of St. Peter’s erected by Constantine from 333, were vast barns with wooden roofs supported on lines of columns. They resembled basilicas, which had carried on the Hellenistic style of columnar architecture. Roman concrete vaulted construction was used in certain cases, for example, in the tomb church in Rome of Constantine’s daughter, Santa Costanza, of about 350.
In the church of San Vitale in Ravenna, erected in 526-547, this was expanded to the scale of a middle-sized church. Here a domed octagon 60 feet (18 meters) across is surrounded by a corridor, or aisle, and balcony 30 feet (9 meters) deep. On each side a semicircular projection from the central space pushes outward to blend these spaces together..