Search results
Results from the WOW.Com Content Network
Prestressed beam without load. Prestressed beam with load. Prestressed concrete is a form of concrete used in construction. It is substantially "prestressed" (compressed) during production, in a manner that strengthens it against tensile forces which will exist when in service. [1][2]: 3–5 [3] It was patented by Eugène Freyssinet in 1928.
An extradosed bridge employs a structure that combines the main elements of both a prestressed box girder bridge and a cable-stayed bridge. [1] [2]: 85 [3] The name comes from the word extrados, the exterior or upper curve of an arch, and refers to how the "stay cables" on an extradosed bridge are not considered as such in the design, but are instead treated as external prestressing tendons ...
Logo of Eurocode 2 An example of a concrete structure. In the Eurocode series of European standards (EN) related to construction, Eurocode 2: Design of concrete structures (abbreviated EN 1992 or, informally, EC 2) specifies technical rules for the design of concrete, reinforced concrete and prestressed concrete structures, using the limit state design philosophy.
A prestressed concrete design method in which the prestressing forces exerted upon the member act to balance a given proportion of the service loads that the member will be subjected to. [1] : 38. longitudinal prestressing. Prestressing forces acting along the longitudinal axis of the member. low point.
(2) The thermal expansion coefficients of concrete and steel are so close (1.0 × 10 −5 to 1.5 × 10 −5 for concrete and 1.2 × 10 −5 for steel) that the thermal stress-induced damage to the bond between the two components can be prevented. (3) Concrete can protect the embedded steel from corrosion and high-temperature induced softening.
Precast concrete is a construction product produced by casting concrete in a reusable mold or "form" which is then cured in a controlled environment, transported to the construction site and maneuvered into place; examples include precast beams, and wall panels, floors, roofs, and piles.
Creep and shrinkage of concrete are two physical properties of concrete. The creep of concrete, which originates from the calcium silicate hydrates (C-S-H) in the hardened Portland cement paste (which is the binder of mineral aggregates), is fundamentally different from the creep of metals and polymers. Unlike the creep of metals, it occurs at ...
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]