Robert L. Hohlfelder

Cement Microstructures and Durability in Ancient Roman Seawater Concretes

Roman hydraulic maritime concretes of the central Italian coast have pumiceous volcanic ash, or pulvis Puteolanus, from the Bay of Naples as mortar pozzolan. Petrographic and mineralogical analyses of cement microstructures in relict lime, tuff, and pumice clasts suggest that pozzolanic reaction at high pH produced gel-like calcium-aluminum-silica-hydrate cements. Orthorhombic 11 A-tobermorite, with unit cell dimensions a = 5.591(1)A, b = 3.695(1)A, c = 22.86(1)A, developed in the residual cores of portlandite clasts and in certain pumiceous clasts, as well. Ettringite and calcium-chloroaluminate formed in discrete, perimetral microstructures and in the cementitious matrix. Phillipsite and chabazite cements may reflect later dissolution of alkali-rich volcanic glass at pH 9–10. The cement systems have remained stable for 2,000 years, during partial to full immersion in seawater. Vitruvius’ De architectura and other ancient texts describe the raw materials of the concretes, preparation of lime, and construction of submerged wooden forms. Information concerning the materials, formulations, and installations of the concretes was apparently spread by movement of central Italian engineers around the Mediterranean but also, perhaps, by the circulation of sub-literary engineering manuals. Further analytical investigations will determine the diverse chemical processes that produced the cement microstructures, and why the harbour constructions have endured for two millennia.

Res Maritimae: Cyprus and the Eastern Mediterranean from Prehistory to Late Antiquity

An interdisciplinary anthology of 26 papers, three in French, pivoting on the study of port cities as gateways to land and sea transportation systems through which moved the people, trade, and ideas of antiquity. Covering approximately 10,000 years from the early Holocene through the Roman period, t

The Caesarea Ancient Harbor Excavation Project (C.A.H.E.P.): Preliminary Report on the 1980–1983 Seasons

AbstractUnderwater and shoreline survey and excavation at the Herodian harbor of Sebastos, the port of Caesarea Maritima on the Mediterranean coast of Israel, have provided important new information on Roman harbor design and construction. Local and imported materials were carefully selected and used to construct two immense breakwaters that framed outer and inner basins. Hydraulic concrete was used in a sophisticated manner, and ingenious sluice gates and a subsidiary breakwater provided protection against siltation and storm damage.

Uncovering the maritime secrets of Aperlae, a coastal settlement of ancient Lycia

At the terminus of one of the Mediterraneans countless exposed bays, open and vulnerable to the ravages of the sea, the fortified town of Aperlae surprisingly boasts an impressive complex of ruins that speak clearly to the towns prosperity. A clue to why Aperlae flourished may be found in the ubiquitous remains of the sea snail murex, the basis of Tyrian purple dye. Aperlae and the submerged ruins of its waterfront offer an attractive arena for maritime archaeology, especially because local ports have not received even a small portion of the attention lavished on advanced international harbors.

Sebastos: Herod's Harbor at Caesarea Maritima

The authors report on recent excavations conducted at this important Mediterranean site.

Images of Homage, Images of Power: King Herod and his Harbour, Sebastos

As the tumultuous Triumviral decades of the Republic ended and the Augustan era began, the shadow of Romes majesty continued to envelop the shores of Judaea some 2000km to the east. King Herod had survived the struggle for dominance between Octavian (Augustus after 27 B.C.) and his rivals, Mark Antony and his ally and wife Cleopatra VII, in part by not being at Actium in 31 B.C. where the final battle in Romes long series of civil wars was fought. Although his fealty had been to Antony, he had managed to be east of his kingdoms borders conducting a military operation against Malichus I of Nabataea, who had been accused of disloyalty by Cleopatra and Herod (Joseph. AJ 15.110).

Sebastos, the Harbor Complex of Caesarea Maritima, Israel: The Preliminary Report of the 1978 Underwater Explorations

From the 28th of May to the 21st of June, 1978, a team of three individuals conducted a preliminary archaeological survey of the harbors and shoreline of Caesarea Maritima, the major Roman and Byzantine city on the coast of ancient Palestine (Frova 1965, Levine 1975a, 1975b, Ringel 1975). This ancient metropolis and its extraordinary port and habor facilities were constructed by Herod the Great at the end of the First Century B.C. (Oestreicher 1962) and were in use until ca. 640 A.D., when the city and its environs fell to Arab conquerors. The site of Caesarea (32°30.5′N, 34°53.5′E) is located ca. 45 km south of the modern city of Haifa on the Mediterranean coast of Israel and now embraces the farms, residences and industries of Kibbutz Sdot Yam.