D69 QUIZ OF THE DAY

Which part of a cantilever retaining wall acts like a vertical cantilever under earth pressure?

• Heel slab
• Toe slab
• Stem
• Shear key

Answer explanation

The stem behaves like a vertical cantilever under the lateral earth pressure from backfill.

The heel slab in a cantilever retaining wall acts as a cantilever in which plane?

• Vertical plane
• Horizontal plane
• Inclined plane
• None

Answer explanation

Heel slab acts as a cantilever in horizontal plane carrying the weight of soil above it.

What is the main structural effect of counterforts in retaining walls?

• Increase overturning
• Reduce bending moments
• Increase wall weight
• Drain water

Answer explanation

Counterforts reduce bending moments in the stem and heel by acting as triangular struts.

Which type of retaining wall is most economical for heights above 15 m?

• Gravity wall
• Semi-gravity wall
• Counterfort wall
• Cantilever wall

Answer explanation

Counterfort retaining walls are most economical for tall walls, even beyond 15 m.

Which non-RCC retaining wall uses stone-filled wire baskets?

• Gabion wall
• Crib wall
• Soil nail wall
• Sheet pile

Answer explanation

Gabion walls consist of stone-filled wire baskets providing mass and drainage.

What is the main purpose of IS 14458?

• Seismic detailing
• Retaining wall design
• Wind load calculation
• Steel structure design

Answer explanation

IS 14458 provides guidelines for design and construction of retaining walls.

Which load is considered using Mononobe-Okabe theory?

• Live load
• Seismic earth pressure
• Wind load
• Dynamic load

Answer explanation

The Mononobe-Okabe theory is used to calculate seismic earth pressure on retaining walls.

In portal frames, which connection type transfers bending moment to the foundation?

• Hinged connection
• Fixed connection
• Slip joint
• Pinned base

Answer explanation

Fixed connections transfer bending moments from the frame to the foundation.

Which IS code provides guidelines for dead and live load values?

• IS 456
• IS 875
• IS 1893
• IS 13920

Answer explanation

IS 875 specifies load calculations for dead, live, wind, and other loads.

What is the main disadvantage of buttressed walls?

• Require more concrete
• Interfere with space on toe side
• Weaker than counterforts
• High maintenance

Answer explanation

Buttresses are placed on the toe side, which can limit usable space.