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How to check quality of cement In A Construction Site

The stability of structure is highly dependent on the quality of cement used.

Workers mix cement at construction site.Workers at a construction site.

Cement is the glue that holds concrete and mortar and brick structures together. The strength, durability and safety of these structures are highly dependent on the quality of cement used.

In light of this fact, it is not only desirable but also sensible to use best quality cement, which can be ascertained by investigating its properties before use.

There are several ways of checking the quality of cement with the following being some of the simple field tests you can perform with no specialised equipment.

1.) Pre purchase

At hardware shop, here is how to check the quality of the cement:

(i) Brand

Being a manufactured product that involves mixing of different components, cement grade varies from one brand to the other. Choose a reputable brand and seller and check for certification to ensure there is adherence to manufacturing standards.

(ii) Production date

Cement loses its strength with time and it is therefore vital to check for date of manufacture. It is best to use cement that has not stayed more than 90 days since the date of manufacture.

2.) Post purchase

Once at the construction site, here is how to check the quality of the cement:

(i) Color test

The color of cement is indicative of the constituent raw materials. Quality cement has a distinctive grey-greenish color that should be uniform in the entire bag. Any variations signify excess lime or excess clay, which must be avoided.

(ii) Temperature test

Cement should feel cool to the touch. You can test this by plunging your hand into the cement bag.

If it feels warm, hydration is taking place in the bag and the quality is compromised.

(iii) Float test

When you place a small amount of cement on water, it should float for a little while before sinking. Continued floating indicates partial settling and air voids while immediate sinking is a sign of impurities.

(iv) Smell test

Cement has a characteristic odour when it reacts with water, which can vary depending on the ratio of components.

To perform the smell test, make a paste with water and smell it. If it has an earthy smell, then too much clay and silt have been used hence affecting the cement grade.

(v) Strength test

Being the agent that holds a building together, the strength of cement is of great importance. To test strength, make a block measuring 1inch by 1inch by 8inches and immerse it in water for 3-7 days. Place it on supports, 6 inches apart and place a 34kg load on it. A block made from quality cement does not show signs of failure.

(vi) Setting test

Cement solidifies when it encounters water in a process known as setting. Quality cement should set without any cracks and it should retain the original shape. To test this, mix cement and water to make a thick rough edged paste and place it on a glass plate. Immerse it in water and check after 24 hours to see the results.

(vii) Texture test

Cement is a very fine powder and high quality cement is smooth to the touch.

Lumps are a sign of moisture contamination while rough particles indicate adulteration with sand. Particle size affects the rate of setting and strengthening. Considering its importance in structure soundness, it is necessary for contractors and clients to know how to check the quality of cement as part of basic precautions in construction.

Content created and supplied by: Precious24 (via Opera News )

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