It is very important to check the water quality of the concrete mix. As a slight change in the chemical composition of water may result in a drastic change in the chemical behaviour of the concrete mix. There are different sources of water available, which may or may not be suitable for concrete mix. Such as reclaimed water, groundwater, treated water from a sewer, and water from a ready-mix concrete plant, etc.
As it is a known fact that in many parts of the world, water is in scarcity or shortage so it is very important to use water efficiently. In such countries, treated effluents are used for concrete mixing, curing, and even for washing aggregate. Water from fresh sources like ponds, river, etc. is also suitable for concrete mixing.
Concrete is a man-made material so it is very much possible for us to change the properties of the concrete mix. In the simplest form concrete is a mixture of coarse aggregate, fine aggregate, water, and cement. The mixture of water and cement called paste act as the binding agent between the coarse and fine aggregate.
By changing the proportion of different materials used, we can alter the properties which will allow us to get the desired quality. The use is not only restricted to the structural application but in the domain of transportation engineering to environmental engineering it is widely used as construction material.
Common classification of water
Based on the quality of water, water is classified as follows:
- Potable water – Water which is suitable for consumption of human being.
- Recycled water – Water which is treated up to acceptable limit which is suitable for its intended use.
- Blackish water: Waste water generated from toilet, urinals which are directly contaminated with human excreta.
- Gray water: Waste water from wash basins, showers, laundries and kitchen.
We should test the quality of water in a laboratory before using in preparing concrete / mortar.
For plain and reinforced cement concrete permissible limits for solids is shown in table as follows:
| Type of solid in water | Permissible limits |
| Organic matter | 200 mg/l |
| Inorganic matter | 3000 mg/l |
| Sulfates | 500 mg/l |
| Chlorides | 1000 mg/l |
| Suspended matters | 2000 mg/l |
The pH of water should be between 6 – 8 to use in concrete mix.
Some of the tests for water quality
Physical Tests
- Turbidity test: measures the amount of suspended solids in water
- Color test: measures the presence of organic and inorganic materials in water
- pH test: measures the acidity or alkalinity of water
- Hardness test: measures the presence of calcium and magnesium ions in water
- Chloride test: measures the presence of chloride ions in water
Chemical Tests
- Total Alkalinity test: measures the amount of basic substances in water
- Total Dissolved Solids test: measures the amount of salts in water
- Total Suspended Solids test: measures the amount of suspended solids in water
- Alkalinity-Acidity test: measures the pH balance of water
- Conductivity test: measures the electrical conductivity of water
Microbiological Tests
- Bacterial tests: measures the presence of harmful bacteria in water, such as E. coli and salmonella
- Fungal tests: measures the presence of fungi in water
- Parasite tests: measures the presence of parasites in water, such as Giardia and Cryptosporidium
Conclusions
In conclusion, the quality of water used in the concrete mix is of utmost importance in the construction industry. Proper water quality ensures the longevity and durability of concrete structures.
Some of the key learnings are as follows:
- Water test : A number of tests, including physical, chemical, and microbiological tests, are used to assess the quality of water.
- Indian standards: It is important to use water that meets the standards set by the construction industry, as well as the local building codes, to ensure the safety and longevity of the finished structure.
- Water quality: Ensuring that the water used in the concrete mix is of proper quality is a critical step in the overall success of a construction project.
These quality tests are important in construction because they help to ensure that the water used in construction is safe, clean, and free from contaminants that could cause harm to the workers, damage to the materials or equipment, or affect the integrity of the final structure.
Check this post for different tests available for aggregate.
This article was crafted by a group of experts at eigenplus to ensure it adheres to our strict quality standards. The individuals who contributed to this article are:
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