D65 MASTER THE DAY

In machine mixing of concrete, which ingredient is generally fed first?

• Cement
• Sand
• Coarse aggregates
• Water

Answer explanation

In machine mixing, coarse aggregates are fed first, followed by sand, then cement, and finally water.

Slump test is used to measure:

• Strength of concrete
• Workability of concrete
• Durability of concrete
• Curing rate

Answer explanation

The slump test measures workability and consistency of fresh concrete on site.

Which slump type indicates segregation and excessive water content?

• True slump
• Shear slump
• Collapse slump
• Zero slump

Answer explanation

Collapse slump occurs when concrete has too much water, leading to loss of cohesion and segregation.

For parapet, slab, walls, and piers, the recommended slump is:

• 20–40 mm
• 40–50 mm
• 80–150 mm
• 90–100 mm

Answer explanation

For parapet, slab, walls, and piers, slump should be between 40–50 mm for optimum workability.

Break lintels usually have a minimum bearing length of:

• 100 mm
• 150 mm
• 200 mm
• 250 mm

Answer explanation

Break lintels typically have a minimum bearing length of 150 mm or span/10.

Continuous lintels reduce mid-span moments but create:

• Shear stresses
• Negative moments at supports
• Bending cracks
• Torsional effects

Answer explanation

Continuous lintels reduce mid-span moments but introduce negative moments at supports.

The projection thickness of chajjas at the tip is usually:

• 25–40 mm
• 50–75 mm
• 80–100 mm
• 100–120 mm

Answer explanation

At the tip, chajjas are typically 50–75 mm thick for economy and structural efficiency.

Which column shape is most common in building construction?

• Circular
• Square/Rectangular
• L-shaped
• Hexagonal

Answer explanation

Square and rectangular columns are easiest for formwork and alignment with walls.

Intermediate columns have slenderness ratio between:

• 8–32
• 32–120
• 120–150
• 150–200

Answer explanation

Intermediate columns have slenderness ratio between 32 and 120, with both buckling and direct stress effects.

Which reinforcement type in columns provides continuous confinement?

• Lateral ties
• Spiral reinforcement
• Cranked bars
• U-stirrups

Answer explanation

Spiral reinforcement provides continuous confinement to core concrete in columns.