D67 MASTER THE DAY

According to IS 456:2000, a slab is called one-way slab when L/B is:

• Less than 1
• Equal to 2
• Greater than 2
• Less than 2

Answer explanation

One-way slabs have a longer span to shorter span ratio greater than 2.

In a one-way slab, the main reinforcement is placed:

• In the longer direction
• In the shorter direction
• Diagonally
• In both directions equally

Answer explanation

Main reinforcement in one-way slabs is placed in the shorter direction where bending occurs.

Minimum reinforcement in slabs using mild steel bars is:

• 0.10%
• 0.12%
• 0.15%
• 0.20%

Answer explanation

Minimum reinforcement for slabs with mild steel is 0.15% of cross-sectional area.

Two-way slabs are identified when L/B ratio is:

• Greater than 2
• Equal to 2
• Less than or equal to 2
• Less than 1

Answer explanation

Two-way slabs have L/B ratio less than or equal to 2 and are supported on all four sides.

Torsion reinforcement at a corner where both edges are continuous is:

• Full torsion reinforcement
• Half torsion reinforcement
• Not required
• Double torsion reinforcement

Answer explanation

No torsion reinforcement is needed at corners where both edges are continuous.

In a two-way slab, the middle strip width is taken as:

• 1/4 of span
• 1/2 of span
• 3/4 of span
• Full span

Answer explanation

Middle strip width is 3/4 of the slab width in that span.

Distribution steel spacing in slabs shall not exceed:

• 3d or 450 mm
• 4d or 450 mm
• 5d or 450 mm
• 6d or 500 mm

Answer explanation

Distribution steel spacing must not exceed 5 times effective depth or 450 mm.

In a one-way slab, alternate bars are cranked at a distance from face of support equal to:

• L/7 for partially fixed slabs
• L/5 for continuous slabs
• Both A and B
• L/4 for simply supported slabs

Answer explanation

Alternate bars are cranked at L/7 for partially fixed slabs and L/5 for continuous slabs.

Effective span of a slab is taken as:

• Clear span only
• Clear span + effective depth
• Larger of clear span + depth or c/c distance
• Smaller of clear span + depth or c/c distance

Answer explanation

Effective span is the smaller of (clear span + depth) or centre-to-centre distance between supports.

Torsion mesh size for a two-way slab corner is:

• 1/4 of short span
• 1/5 of short span
• 1/6 of short span
• 1/8 of short span

Answer explanation

Torsion mesh size is 1/5 of the short span.