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Famous concrete structures include the Hoover Dam, the Panama Canal and the Roman Pantheon.The earliest large-scale users of concrete technology were the ancient Romans, and concrete was widely used in the Roman Empire.

Concrete, as the Romans knew it, was a new and revolutionary material.Laid in the shape of arches, vaults and domes, it quickly hardened into a rigid mass, free from many of the internal thrusts and strains that troubled the builders of similar structures in stone or brick.Known for its 250 live music venues and distinct downtown entertainment districts, Austin, Texas will play host to the 2018 MCAA Midyear Meeting.We look forward to welcoming you to Austin this September!Aspdin chose the name for its similarity to Portland stone, which was quarried on the Isle of Portland in Dorset, England.

His son William continued developments into the 1840s, earning him recognition for the development of "modern" Portland cement.

Second, integral reinforcing steel gives modern concrete assemblies great strength in tension, whereas Roman concrete could depend only upon the strength of the concrete bonding to resist tension.

The long-term durability of Roman concrete structures has been found to be due to its use of pyroclastic (volcanic) rock and ash, whereby crystallization of strätlingite and the coalescence of calcium–aluminum-silicate–hydrate cementing binder helped give the concrete a greater degree of fracture resistance even in seismically active environments.

is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens over time—most frequently a lime-based cement binder, such as Portland cement, but sometimes with other hydraulic cements, such as a calcium aluminate cement.

It is distinguished from other, non-cementitious types of concrete all binding some form of aggregate together, including asphalt concrete with a bitumen binder, which is frequently used for road surfaces, and polymer concretes that use polymers as a binder.

From the 14th century to the mid-18th century, the use of cement gradually returned.