D41 FACE THE CHALLENGE

Assertion (A): Low heat cement is preferred for mass concrete works. Reason (R): It generates less heat of hydration compared to ordinary Portland cement.

• Both A and R are true and R is the correct explanation of A
• Both A and R are true but R is not the correct explanation of A
• A is true but R is false
• A is false but R is true

Answer explanation

Low heat cement contains more C2S and less C3A, reducing heat during hydration—ideal for mass concreting.

Match the function keys in AutoCAD with their functions:

• F3 – Object snap, F7 – Grid, F8 – Ortho, F9 – Snap
• F3 – Grid, F7 – Ortho, F8 – Snap, F9 – Object snap
• F3 – Snap, F7 – Object snap, F8 – Grid, F9 – Ortho
• F3 – Ortho, F7 – Snap, F8 – Object snap, F9 – Grid

Answer explanation

F3: Osnap, F7: Grid, F8: Ortho, F9: Snap – commonly used for drawing precision.

What is the slope of a typical road-side kerb ramp as per standard practice?

• 1:3
• 1:5
• 1:12
• 1:20

Answer explanation

1:12 is a standard slope used for kerb ramps ensuring smooth vehicular access.

In which cement type is volcanic ash used as one of the ingredients?

• Quick setting cement
• Pozzolana cement
• High alumina cement
• White cement

Answer explanation

Pozzolana cement includes volcanic ash to improve sulphate resistance and reduce heat of hydration.

Which of the following causes efflorescence in cement?

• Magnesia
• Alumina
• Sulphur
• Alkalis

Answer explanation

Alkalis are responsible for white salt deposits on cement surfaces, causing efflorescence.

Which command is used to create a 3D solid by rotating a 2D object around an axis?

• Extrude
• Sweep
• Revolve
• Loft

Answer explanation

Revolve command is used to rotate 2D profiles around an axis to create 3D solids.

Which of the following is not an advantage of Bar Bending Schedule?

• Minimizes steel wastage
• Helps in quality control
• Prevents formwork failure
• Supports automation

Answer explanation

BBS does not directly prevent formwork failure.

The point where whole weight of a body acts is called:

• Centroid
• Centre of gravity
• Moment of inertia
• Radius of gyration

Answer explanation

Centre of gravity is the point of action of the whole weight of a body.

In fluid mechanics, Pascal’s law states that pressure applied to a fluid is:

• Reduced in all directions
• Transmitted equally in all directions
• Only in the direction of gravity
• Only upward

Answer explanation

Pascal's law: pressure at a point in static fluid is equal in all directions.

Which element in cement acts as a flux and reduces clinkering temperature?

• Silica
• Alumina
• Lime
• Iron Oxide

Answer explanation

Alumina acts as a flux during clinkering and helps reduce the fusion temperature.