Modern concrete architecture has a pitiful shelf life compared to ancient structures. There is a simple solution
A pair of Australian bridges try to cure concrete cancer
Using composite reinforcing
Science and technology Oct 31st 2019 edition
Oct 31st 2019
Modern civilisation is built on concrete and steel. Put the two together, though, and you can generate a problem. Reinforcing concrete with steel rods called rebars is the basis of modern construction. But because water gets in through tiny cracks, the rebars rust. This causes them to expand, widening the cracks and weakening the concrete. Hence such structures require constant attention and often have design lives of only 60-100 years. That is pitiful compared with, say, the concrete dome of the Pantheon in Rome—which was completed in 125AD and still stands.
Various ways of delaying or preventing concrete cancer, as this corrosion is known colloquially, have been tried. These include recipes for concrete that is less permeable to water, and rebars made from rust-resistant materials such as stainless-steel or composites. Such approaches work, but they can be expensive.
Rebar (short for reinforcing bar), known when massed as reinforcing steel or reinforcement steel, is a steel bar or mesh of steel wires used as a tension device in reinforced concrete and reinforced masonry structures to strengthen and aid the ...
鋼筋是一種鋼製的條狀物，是建築材料的一種。例如在鋼筋混凝土之中，用於支撐結構的骨架。鋼筋抗拉不抗壓，混凝土抗壓不抗拉，兩者結合後有很好的機械強度，鋼筋受到混凝土的保護而不致生鏽，而且鋼筋與混凝土有著近似相同的熱膨脹係數，比較不會產生裂縫而腐蝕，因此成為現代建築的理想材料，成為廣泛使用的鋼筋混凝土建築。
Etymology 1[edit]
Pronunciation[edit]
Noun[edit]
- (countable) A steel reinforcing bar in a reinforced concrete structure.
- (uncountable) A grid-shaped system of such bars.
Translations[edit]
Etymology 2[edit]
Pronunciation[edit]
Verb[edit]
rebar (third-person singular simple present rebars, present participle rebarring, simple past and past participle rebarred)
- (transitive) To bar again.
- After allowing the stranger to enter, she rebarred the door.
- (music, transitive) To redistribute the notes of a musical score across the bars, e.g. when changing time signature.
Anagrams[edit]
Latin[edit]
Verb[edit]
rēbar
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