GATE 2025 ADVANCED CONCRETE TECHNOLOGY MCQ

 

1. Type III cement in ASTM C150 (as compared to Type I) –

 Has higher percentage of C3S, more fineness and more heat of hydration

 Has higher percentage of C3S, less fineness and more heat of hydration

 Has higher percentage of C3S and C2S, more fineness and more heat of hydration

 Has higher percentage of C2S and C3A, more fineness and more heat of hydration

Accepted Answers:

Has higher percentage of C3S, more fineness and more heat of hydration

2. choose the correct representation for Portland (fly ash) cement with 30% calcareous fly ash that falls in the 28-day strength class of 42.5 MPa under normal strength development conditions.

 CEM II B-V 42.5N

 CEM II A-W 42.5N

 CEM II A-V 42.5N

 CEM II B-W 42.5N

Accepted Answers:

CEM II B-V 42.5N

3. Arrange the following in the order of heat of hydration

 C3A>C3S>C4AF>C2S

 C3S>C3A>C4AF>C2S

 C3A=C3S>C4AF>C2S

 C2S>C3S=C4AF>C3A

Accepted Answers:

C3A>C3S>C4AF>C2S

4.  As the water to cement ratio in cement mortar increases (more than one option is correct)

 Dormant period duration decreases

 Compressive strength at 28 days decreases

 Peak heat rate decreases

 Peak temperature reached during hydration increases

 The time to reach the peak remains unaffected

Accepted Answers:

Compressive strength at 28 days decreases ,Peak heat rate decreases

5 . Assertion (A): C-S-H has a layered configuration as per Feldman Sereda model
Reason (R): The structure of CSH is crystalline

 Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of Assertion (A).

 Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).

 Assertion (A) is true, but Reason (R) is false.

 Assertion (A) is false, but Reason (R) is true.

 Both Assertion (A) and Reason (R) are false.

Accepted Answers:

Assertion (A) is true, but Reason (R) is false.