Influence from ingredients

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Main influencing factors of Workability

• Influence from ingredients
• W/C
• Quantity of paste
• Sp
• Aggregates
• Admixture
• Influence from environment
• Time
• Temperature
• Test condition

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Main influencing factors of Workability
Influence of quantity of paste

• Quantity of paste
• (quantity of mixing water ,ratio of paste
  to aggregate)
• -When W/C is fixed
• Quantity of paste is crucial in obtaining
  Workability and volume stability

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Influence of Quantity of paste

• Proper quantity of paste can meet the
  requirements of mobility, viscidity and capacity
  of water retention.
• It should be determined by the requirements of
  construction.

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How to adjust mobility

• Function of water
• Water is essential to hydrate Portland cement and
  provides Workability to concrete mixtures.
• The mixture with too much water is detrimental to
  concrete quality.

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Reason

• Dont add water separately
• When the mobility of composite is to be adjusted,
  adding water separately will cause segregation
  and deteriorate the strength and durability of
  concrete.

• Harmfulness of adding too much water
• More water than required to hydrate Portland
  cement dilutes the paste, separates the calcium
  silicate gel crystals, and weakens the gel
  structure. Uncombined water leaves capillary
  voids in the paste, which are involved in most
  freezing and thawing mechanisms.

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How to adjust mobility
Proper method

• The proper method is to alter the quantity of
  cement paste to improve the mobility with the
  stability of W/C.