Self consolidating concrete wiki
The earliest large-scale users of concrete technology were the ancient Romans, and concrete was widely used in the Roman Empire.The Colosseum in Rome was built largely of concrete, and the concrete dome of the Pantheon is the world's largest unreinforced concrete dome.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.
Its widespread use in many Roman structures, a key event in the history of architecture termed the Roman Architectural Revolution, freed Roman construction from the restrictions of stone and brick materials.
It enabled revolutionary new designs in terms of both structural complexity and dimension.
Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens over time.
Most concretes used are lime-based concretes such as Portland cement concrete or concretes made with other hydraulic cements, such as calcium aluminate cements.
From the 14th century to the mid-18th century, the use of cement gradually returned.
The Canal du Midi was built using concrete in 1670.Small-scale usage of concrete has been documented to be thousands of years old.Concrete-like materials were used since 6500 BC by the Nabataea traders or Bedouins, who occupied and controlled a series of oases and developed a small empire in the regions of southern Syria and northern Jordan.The cement reacts chemically with the water and other ingredients to form a hard matrix that binds the materials together into a durable stone-like material that has many uses.Often, additives (such as pozzolans or superplasticizers) are included in the mixture to improve the physical properties of the wet mix or the finished material.Today, large concrete structures (for example, dams and multi-storey car parks) are usually made with reinforced concrete.Tags: Adult Dating, affair dating, sex dating