Effects of too much water in concrete
If additional water is present in concrete mix, the concrete can be set easily but the strength & quality of the concrete is reduced significantly. Due to additional water, the damage to concrete structures occurs in the following was :-
1. Strength Reduction 2. Drying shrinkage 3. Loss of abrasive resistance 4. Rise in permeability 5. Dusting and scaling 6. Reduced durability
1. Strength Reduction: Compressive strength is a vital characteristic of solidified concrete and it is decreased due to redundant quantity of water in concrete. The additional water will not engage in the hydration process and contain in concrete even after being solidified.
When the water is vulnerable to atmosphere, it vaporizes and produces voids in the concrete and these voids will decrease the compressive strength of concrete.
2. Drying Shrinkage: If water-cement ratio is raised, the drying shrinkage is also raised and concrete become poor in tensile strength and consequently, cracks build up on the concrete surface.
3. Loss of Abrasive Resistance: Abrasive resistance of concrete is related to its strength directly. With the rise in additional water quantity in concrete, the strength of the concrete is reduced and as a result, the abrasive resistance is also decreased.
4. Permeability: The concrete gets permeable once the additional water in solidified concrete is evaporated. The voids created due to evaporation, will consume water and transform the concrete structure permeable.
5. Dusting: The additional water in concrete mix fetches the fine aggregate to the top, therefore, after getting solidified, a fine loose powder will be arranged on the top of the concrete surface. This method is known as dusting.
6. Scaling: Because of additional water content in concrete, scaling of concrete happens. Under this situation, the top layer of the solidified concrete surface is detached. It is caused by the reaction of water with freeze and thaw effects./p>
7. Reduced durability: The above-explained effects finally result in decreasing the stability of concrete. So, it is necessary to maintain the exact water cement ration for the development of long-lasting concrete. Low water-cement ratio facilitates to produce more long-lasting concrete. By including air entraining admixtures, the longevity is enhanced with low water content.