Write the significance of water-cement ratio and its effect on hydration of cement.

Write the significance of water-cement ratio and its effect on hydration of cement.
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Significance of water-cement ratio: The W/C ratio plays very vital role in concrete mixture. The improper or random selection of W/C ratio leads in various defects in fresh and hardened concrete. If W/C ratio is less (say w/c= 1/4 = 0.25), then concrete will become harsh and results in honeycombing or porous nature due to poor workability. If w/c ratio is more ((say w/c= 5/4= 1.25), then concrete undergoes segregation and bleeding. Thus finally concrete shows defects in it. Therefore w/c ratio should be optimum, which depends on grade of concrete and exposure conditions hence w/c ratio should be selected from IS: 456:2000. If w/c ratio is opted out properly as mentioned above, then concrete possess good workability, compressive strength and durability ultimately


Effect of water-cement ratio on hydration of cement: When w/c ratio is less i.e. less water in concrete mix, then it leads to less availability of water than that of required for complete hydration. It decreases the rate of hydration of cement. When w/c ratio is more i.e. excessive water in concrete, then it results in abundant availability of water for sufficient hydration. But such large water may not give proper binding of aggregates.

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Related questions

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