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why do we use cranked rebar at rebar overlapping?

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 Cranked bars are produced by slightly bending the reinforcement bar before the overlapping zone then straightening it at the overlapping zone, as shown in figure no:1. The main purpose of this practice is to reduce the congestion of reinforcement at the overlapping zone for structure members with a high amount of reinforcement. The use of crank bars will give flexibility in fixing and arranging reinforcement to reduce the congestion, which helps create a larger space between reinforcement rebars. The spacing between reinforcement rebars should be sufficient to allow smooth concrete placement. Small spacing of reinforcement rebar will work as a screen that will enable the concrete paste to pass through it and stop aggregate, which results in concrete segregation. Therefore, cranked rebars can be used to slightly reduce the congestion of reinforcement rebars and increase the spacing between rebars.

Figure no:1



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My name is Mohammad Hamdan, and I am a Civil/bridge Engineer with extensive professional background and experience in the field of construction. I have 10+ years of experience in the construction field. During my professional career, my emphasis has been placed on structural projects, mainly bridges, infrastructure and roads. Reading and practicing the design of structures is my passion.i was lucky to be a part of a big team that executed major highway interchanges. I believe in spreading the knowledge, thus, i compose these courses to share my experience and knowledge. My course focuses on the practical side of construction field. On other word, i am sharing some of what new engineers need to know about construction field. Beside working on construction field, i love writing some articles on my website ( curious civil engineer) Moreover, i wrote some engineering papers, you can check them  by searching my name on Google (Mohammad mamon Hamdan)