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Figure 2 - Failure probability and target service life in performance-based service life models for reinforced concrete structures. Performance-based approaches provide for a real design of durability, based on models describing the evolution in time of degradation processes, and the definition of times at which defined limit states will be ...
Their addition allows to decrease the water-to-cement ratio of concrete or mortar without negatively affecting the workability of the mixture. It enables the production of self-consolidating concrete and high-performance concrete. The water–cement ratio is the main factor determining the concrete strength and its durability. Superplasticizers ...
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]
(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.
Fibers are added for long term durability of concrete. Glass [14] and polyester [15] decompose in alkaline condition of concrete and various additives and surface treatment of concrete. The High Speed 1 tunnel linings incorporated concrete containing 1 kg/m 3 or more of polypropylene fibers, of diameter 18 & 32 μm, giving the benefits noted ...
2)) present in the hardened cement paste to give gypsum: H 2 SO 4 + Ca(OH) 2 → CaSO 4 · 2H 2 O. When concrete is carbonated by atmospheric carbon dioxide (CO 2), or if limestone aggregates are used in concrete, H 2 SO 4 reacts with calcite (CaCO 3) and water to also form gypsum while releasing CO 2 back to the atmosphere: H 2 SO 4 + CaCO 3 ...
An abandoned concrete barge has been sitting off the coast of DuPont for more than 60 years. If you time it right, at low tide you can follow a long sandbar littered with barnacled logs and metal ...
Concrete is used extremely widely in building and civil engineering structures, due to its low cost, flexibility, durability, and high strength. It also has high resistance to fire. Concrete is a non-linear, non-elastic and brittle material. It is strong in compression and very weak in tension. It behaves non-linearly at all times.