FRIDAY WEEKLY EXAM (20/06/2025)

A rectangular beam has a span of 6 m and a total deflection of 20 mm. What is the deflection ratio?

• 1/300
• 1/250
• 1/400
• 1/500

Answer explanation

Deflection ratio = Span / Deflection = 6000/20 = 300.

Assertion (A): Compaction of concrete is essential. Reason (R): Compaction eliminates air voids and increases strength.

• A and R are true, R explains A
• A and R are true, R doesn't explain A
• A true, R false
• A false, R true

Answer explanation

Compaction increases density, reduces voids, improves strength.

Statement I: Plane table surveying is suitable for small-scale mapping. Statement II: It provides high accuracy in hilly terrain.

• Both are true
• Only I is true
• Only II is true
• Both are false

Answer explanation

Plane table is good for small area but not ideal in difficult terrain.

Assertion (A): Rate analysis helps in project cost estimation. Reason (R): It includes material, labor, tools, and overheads.

• A and R are true, R explains A
• A true, R false
• A false, R true
• Both are false

Answer explanation

Rate analysis evaluates cost/unit by including all relevant components.

The value of 1 hectare in m² is:

• 1000
• 10000
• 100000
• 1000000

Answer explanation

1 hectare = 10,000 m² (standard conversion).

For a trapezoidal canal section, the area is calculated using:

• A = b × h
• A = (b + h) × 2
• A = (b + t) × h
• A = (b₁ + b₂)/2 × h

Answer explanation

Trapezoidal area = (base1 + base2)/2 × height.

Assertion (A): Fly leveling is used in route surveys. Reason (R): It involves leveling between two fixed benchmarks only.

• A and R are true, R explains A
• A true, R false
• A and R are true, R doesn’t explain A
• A false, R true

Answer explanation

Fly leveling is used between temporary points; not limited to benchmarks.

In brick masonry, the frog should be placed:

• Upward for better bonding
• Downward for aesthetic finish
• Downward when plastered
• Either way

Answer explanation

Frog (indentation) faces upward to retain mortar and improve bonding.

The primary advantage of diaphragm walls in deep foundations is:

• Flexibility
• Durability
• Waterproofing and soil retention
• Economy

Answer explanation

Diaphragm walls retain soil and prevent groundwater ingress in deep excavations.

Statement I: RCC lintel distributes load over opening. Statement II: Lintels must be reinforced for shear only.

• Both are true
• Only I is true
• Only II is true
• Both are false

Answer explanation

Lintels resist bending and shear; reinforcement is provided for both.