It is not uncommon that steel reinforcement is bent prior to installation into concrete structure. However, upon bending process steel reinforcement may fracture owing to the following reasons:
(i) The ribs on steel bars serve as location of stress concentration which is a potential weak point for fracturing.
(ii) Owing to their intrinsic high strength, large force is required during the bending process.
(iii) The radius of bending is too tight.
Temperature is also an important factor for controlling the risk of steel fracture. The risk of fracture is increased when there is a drop of temperature because steel has lower toughness at low temperatures.
Therefore, bend test are carried out for reinforcing steel to testify their bending performance.
This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.
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