Question

what will be impact of already present Moisture content in coarse and fine aggregates on Water Cement Ratio?

Answer 1

IF THE WATER CONTENT OR MOISTURE CONTENT PRESENT IN COARSE AND FINE AGGREGATE THAT GREATLY EFFECT THE WATER CEMENT RATIO (W/C).....BECAUSE WE DESIGN FOR ONE WATER CEMENT RATIO AND DUE TO THIS AGGREGATE MOISTURE CONTENT DESIGNED WATER CONTENT INCREASES

Two of the most commonly specified requirements for concrete used in the manufactured concrete products industry are the design compressive strength (f’ c) and the maximum water-to-cement ratio (w/c).

THE IMPACTS ARE:

These two values i,e w/c ratio and compressive strength  are inversely related, which means that as the water-to-cement ratio increases, the compressive strength decreases.

Not only does the w/c ratio have a strong influence on compressive strength, but it also affects the permeability and ultimately the durability of the concrete.

Due to less durability life span of structure also decreases ....again reconstruction or repairing works are required and it leads to expensive cost.

When the w/c ratio increases beyond the practical limit the concrete exibits a tendency for separation of constituent particles ( Segregation ) and some of the water also comes out of concrete(Bleeding)

The Workability increases with increase in water cement ratio, but higher water cement ratio can lead to bleeding and segregation of concrete mixture.

What ever is the water content, the water need to be evaporated. For higher water cement ratio more will be the water, more will be the evaporation, MORE WILL BE THE VOIDS IN CONCRETE. Automatically the aesthetical appeareance will lose.....