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The tremie concrete placement method uses a vertical or nearly vertical pipe, through which concrete is placed by gravity feed below water level. [4]The lower end of the pipe is kept immersed in fresh concrete so that concrete rising from the bottom displaces the water above it, thus limiting washing out of the cement content of the fresh concrete at the exposed upper surface.
Self-consolidating concrete or self-compacting concrete (SCC) [1] is a concrete mix which has a low yield stress, high deformability, good segregation resistance (prevents separation of particles in the mix), and moderate viscosity (necessary to ensure uniform suspension of solid particles during transportation, placement (without external compaction), and thereafter until the concrete sets).
Concrete has a very low coefficient of thermal expansion, and as it matures concrete shrinks. All concrete structures will crack to some extent, due to shrinkage and tension. Concrete which is subjected to long-duration forces is prone to creep. The density of concrete varies, but is around 2,400 kilograms per cubic metre (150 lb/cu ft). [1]
In 1875, the first iron-reinforced concrete bridge ever built was constructed at the Castle of Chazelet. Monier was the designer. The important point of Monier's idea was that it combined steel and concrete in such a way that the best qualities of each material were brought into play. Concrete is easily procured and shaped.
Cement-mortar lined ductile iron pipe is a ductile iron pipe with cement lining on the inside surface, and is commonly used for water distribution. Cement-mortar lined ductile iron pipe is governed by standards set forth by DIPRA ( Ductile Iron Pipe Research Association ), and was first used in 1922 in Charleston, South Carolina .
Going (UK), track condition (US) or track rating (AUS) are the track surface of a horse racing track prior to a horse race or race meet. The going is determined by the amount of moisture in the ground and is assessed by an official steward on the day of the race. The condition of a race track plays an important role in the performance of horses ...
Aerated concrete produced by the addition of an air-entraining agent to the concrete (or a lightweight aggregate such as expanded clay aggregate or cork granules and vermiculite) is sometimes called cellular concrete, lightweight aerated concrete, variable density concrete, Foam Concrete and lightweight or ultra-lightweight concrete, [18] [19 ...
Unlike traditional concrete structures, polymer concrete requires no coating or welding of PVC-protected seams. [4] It can also be used as a bonded wearing course for asphalt pavement, for higher durability and higher strength upon a concrete substrate, and in skate parks, as it is a very smooth surface. [citation needed]