Water is used for construction purposes of Civil Engineering Works such as the construction of earth structures, highway construction, mortar and concrete works, etc. Although water is an important constituent of construction materials, it does not receive the attention due to it particularly in the construction of earth structures and highway construction.
However, due importance is given in case of preparation of mortar and concrete. The general belief is that if it is suitable for drinking, then it is considered suitable for construction including mortar and concrete. The quality of water in connection with the preparation of mortar and concrete and for curing is further discussed.
As water helps to form cement gel, which is the governing factor for the strength of mortar or concrete, the quantity and quality of water are to be carefully decided.
The quality of mixing water may be determined based on any one of the following approaches:
- If the water is obtained from an unknown source, the strength of the mortar or concrete made with questionable water is compared with similar mortar or concrete prepared with pure water.
- If the pH value of water lies between 6 and 8, the water is assumed to be free from organic matter and declared as suitable.
The presence of the following impurities may affect the mortar if excess quantity is allowed:
- Presence of suspended particles ≯ 0.02%
- Presence of salts: chlorides ≯ 10,000 ppmsulphates ≯ 3,000 ppm
- Presence of acids and alkalis: harmful
- Presence of algae: harmful
The guidelines to assess the quality of water for concrete discussed in Section 8.4.3 and Table 8.1 are also applicable for mortar.
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