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The following information related to ordinary portland cement is available. a) Initial setting time - 30 min, b) Final setting time - 10 hours c) Cement water combination action - 10% So which of the following statements is true?

The following information related to ordinary portland cement is available. a) Initial setting time - 30 min, b) Final setting time - 10 hours c) Cement water combination action - 10% So which of the following statements is true? Correct Answer a and b

Properties of Portland cement:

Properties

Value

Initial setting time

Should not be less than 30 min

Final setting time

Should not be greater than 10 hrs

Fineness

% Residue by weight should not be greater than 10%

Soundness

Should not be greater than 10 mm

Specific gravity

3.15

Compressive strength after 3 days

Compressive strength after 7 days

15 N/mm2

22 N/mm2

Additional Information

Ordinary Portland cement:

As per IS269, this is the cement used for normal concrete construction.

It has adhesive and cohesive properties so as to render it to form a good bond with other materials.

Portland cement is the most important type of cement and wisely used. It consists of the following component:

Approximate oxide composition limits of ordinary portland cement are as follows:

Oxide

Percentage Content

CaO

60 - 67

Si02

17 - 25

Al2O3

03 - 08

Fe2O3

0.5 - 6.0

MgO

0.1 - 4.0

Alkalies (K2O, Na2O)

0.4 - 1.3

SO3

1.3 - 3.0

 

Related Questions

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