SATURDAY WEEKLY EXAM (21/06/2025)

Which of the following is NOT a component of a septic tank?

• Baffle wall
• Vent pipe
• Soak pit
• Pillar footing

Answer explanation

Pillar footing is unrelated to septic tanks, which are used for sewage treatment and require soak pits, baffles, and vents.

Which type of footing is used when the column is placed near a property line?

• Isolated footing
• Combined footing
• Strap footing
• Raft footing

Answer explanation

Strap footing connects an eccentric footing to an interior footing using a beam to balance load.

Which curve is used to connect two straight roads meeting at a sharp angle?

• Simple curve
• Reverse curve
• Compound curve
• Transition curve

Answer explanation

Compound curves are a combination of two or more simple curves with different radii, suitable for sharp angles.

Which of the following statements is correct regarding the degree of static indeterminacy (Ds) of a plane frame?

• Ds = 3m - 3j + R
• Ds = m - 2j + R
• Ds = 3m - j + R
• Ds = m - j + R

Answer explanation

For a plane frame: Ds = 3m - 3j + R, where m = members, j = joints, R = reactions.

In a three-hinged parabolic arch with uniform load, the horizontal thrust is:

• wL/4
• wL/8
• wL²/8h
• 2wL²/h

Answer explanation

In a parabolic arch with uniform load, horizontal thrust = wL²/8h.

What is the purpose of rocker bearing in bridges?

• To allow rotation and accommodate expansion
• To restrain horizontal movement
• To support live load only
• To increase stiffness of deck

Answer explanation

Rocker bearings allow rotation and expansion due to temperature/live loads in bridge decks.

The modulus of toughness is represented by:

• Total area under stress-strain curve
• Area under elastic limit
• Slope of stress-strain curve
• Ratio of yield stress to strain

Answer explanation

Toughness is the total area under stress-strain curve, representing energy absorbed till fracture.

A simply supported beam of span 6 m carries a point load of 10 kN at midspan. What is the maximum bending moment?

• 10 kNm
• 15 kNm
• 30 kNm
• 15 kNm

Answer explanation

Max BM for point load at midspan = WL/4 = (10*6)/4 = 15 kNm.

Creep in rails is primarily caused by:

• Temperature variations
• Loose fastenings
• Action of braking and acceleration
• Misalignment of joints

Answer explanation

Creep is primarily caused by traction and braking forces which induce longitudinal forces.

The section modulus of a rectangular section (b— d) is given by:

• bd²/12
• bd²/6
• b²d/6
• b²d/12

Answer explanation

Section modulus Z = I/y = (bd³/12)/(d/2) = bd²/6.