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concrete workability

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 concrete workability is a property of concrete determining the ease of mixing, placing and compacting concrete with minimum loss of homogeneity.







Factors affecting workability 

  1. W/C: increasing of water-cement ratio will increase concrete workability but it will reduce the strength of the concrete mix. increasing water-cement ration will increase concrete permeability and this will reduce concrete strength and durability. on the other hand, using concrete with little water insufficient to interact with cement particle to cause hydration this will result in strength reduction. W/C usually ranges from 0.35-0.40.
  2. size of aggregate: Bigger size of aggregate means lesser surface area. as a result, the amount of water required for wetting the aggregate surface is lesser than the smaller size.and this will result in higher workability for the same water content.
  3. the shape of aggregate: aggregate with elongated flaky shapes will reduce the workability of concrete compared to round or cubical aggregate.
  4. Grading of aggregate: well-graded aggregate will enhance concrete mix workability. when the voids are reduced, extra paste will be available to give better lubricating effects.
  5. using of admixture: adding of admixture such as superplasticizers helps in increasing concrete mix workability and reduce W/C. 
Measuring concrete workability

concrete workability can be measured using one of these tests:
adding water to increase concrete workability at the field(for ready-mix concrete) is highly prohibited because it will increase concrete permeability and this will reduce strength and durability of concrete.

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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)