RCC Fundamentals interview questions

1. A.the two materials act together because their thermal coefficients are nearly equal (about 12×10⁻⁶ per °C), bond is good and concrete protects steel from corrosion and fire
2. B.strength below which not more than 5 percent of test results are expected to fall, so M25 means a 28-day cube strength of 25 N/mm²
3. C.steel yields before concrete crushes, giving large deflection and visible cracking as warning, which is why codes require this failure mode
4. D.concrete crushes before steel yields, producing a sudden brittle failure without warning, so limit state design prohibits it

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1. A.Doubly reinforced beam
2. B.Steel–concrete compatibility
3. C.Under-reinforced section
4. D.Limiting moment of resistance

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1. A.Steel–concrete compatibility — Mu,lim = 0.36 fck b xu,max (d − 0.42 xu,max), the largest moment a singly reinforced section can carry under limit state
2. B.Steel–concrete compatibility — concrete compression is parabolic-rectangular with peak stress 0.446 fck, total force 0.36 fck b xu acting 0.42 xu below the compression face
3. C.Steel–concrete compatibility — the two materials act together because their thermal coefficients are nearly equal (about 12×10⁻⁶ per °C), bond is good and concrete protects steel from corrosion and fire
4. D.Steel–concrete compatibility — a slab spans one way when the longer-to-shorter span ratio exceeds 2; below 2 it bends in both directions and is designed as two-way

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1. A.concrete compression is parabolic-rectangular with peak stress 0.446 fck, total force 0.36 fck b xu acting 0.42 xu below the compression face
2. B.a slab spans one way when the longer-to-shorter span ratio exceeds 2; below 2 it bends in both directions and is designed as two-way
3. C.strength below which not more than 5 percent of test results are expected to fall, so M25 means a 28-day cube strength of 25 N/mm²
4. D.steel yields before concrete crushes, giving large deflection and visible cracking as warning, which is why codes require this failure mode

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1. A.Limiting neutral axis depth
2. B.Under-reinforced section
3. C.Over-reinforced section
4. D.Characteristic strength

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1. A.Characteristic strength — compression steel is added when the factored moment exceeds the limiting moment and the section depth is restricted by headroom or architecture
2. B.Characteristic strength — strength below which not more than 5 percent of test results are expected to fall, so M25 means a 28-day cube strength of 25 N/mm²
3. C.Characteristic strength — Mu,lim = 0.36 fck b xu,max (d − 0.42 xu,max), the largest moment a singly reinforced section can carry under limit state
4. D.Characteristic strength — a slab spans one way when the longer-to-shorter span ratio exceeds 2; below 2 it bends in both directions and is designed as two-way

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1. A.compression steel is added when the factored moment exceeds the limiting moment and the section depth is restricted by headroom or architecture
2. B.steel yields before concrete crushes, giving large deflection and visible cracking as warning, which is why codes require this failure mode
3. C.concrete crushes before steel yields, producing a sudden brittle failure without warning, so limit state design prohibits it
4. D.section in which concrete reaches its limiting strain of 0.0035 at the same instant that tension steel reaches its yield strain

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1. A.Under-reinforced section
2. B.Over-reinforced section
3. C.Balanced section
4. D.Limit state stress block

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1. A.Balanced section — Mu,lim = 0.36 fck b xu,max (d − 0.42 xu,max), the largest moment a singly reinforced section can carry under limit state
2. B.Balanced section — strength below which not more than 5 percent of test results are expected to fall, so M25 means a 28-day cube strength of 25 N/mm²
3. C.Balanced section — section in which concrete reaches its limiting strain of 0.0035 at the same instant that tension steel reaches its yield strain
4. D.Balanced section — concrete crushes before steel yields, producing a sudden brittle failure without warning, so limit state design prohibits it

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1. A.Mu,lim = 0.36 fck b xu,max (d − 0.42 xu,max), the largest moment a singly reinforced section can carry under limit state
2. B.xu,max/d is 0.53 for Fe250, 0.48 for Fe415 and 0.46 for Fe500, the cap that keeps a section from becoming over-reinforced
3. C.steel yields before concrete crushes, giving large deflection and visible cracking as warning, which is why codes require this failure mode
4. D.a slab spans one way when the longer-to-shorter span ratio exceeds 2; below 2 it bends in both directions and is designed as two-way

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1. A.Characteristic strength
2. B.Limiting moment of resistance
3. C.One-way vs two-way slab
4. D.Under-reinforced section

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1. A.One-way vs two-way slab — concrete compression is parabolic-rectangular with peak stress 0.446 fck, total force 0.36 fck b xu acting 0.42 xu below the compression face
2. B.One-way vs two-way slab — strength below which not more than 5 percent of test results are expected to fall, so M25 means a 28-day cube strength of 25 N/mm²
3. C.One-way vs two-way slab — xu,max/d is 0.53 for Fe250, 0.48 for Fe415 and 0.46 for Fe500, the cap that keeps a section from becoming over-reinforced
4. D.One-way vs two-way slab — a slab spans one way when the longer-to-shorter span ratio exceeds 2; below 2 it bends in both directions and is designed as two-way

Answer + AI explanation with Pro

1. A.Mu,lim = 0.36 fck b xu,max (d − 0.42 xu,max), the largest moment a singly reinforced section can carry under limit state
2. B.steel yields before concrete crushes, giving large deflection and visible cracking as warning, which is why codes require this failure mode
3. C.concrete crushes before steel yields, producing a sudden brittle failure without warning, so limit state design prohibits it
4. D.the two materials act together because their thermal coefficients are nearly equal (about 12×10⁻⁶ per °C), bond is good and concrete protects steel from corrosion and fire

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1. A.One-way vs two-way slab
2. B.Under-reinforced section
3. C.Doubly reinforced beam
4. D.Limiting neutral axis depth

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1. A.Under-reinforced section — steel yields before concrete crushes, giving large deflection and visible cracking as warning, which is why codes require this failure mode
2. B.Under-reinforced section — Mu,lim = 0.36 fck b xu,max (d − 0.42 xu,max), the largest moment a singly reinforced section can carry under limit state
3. C.Under-reinforced section — the two materials act together because their thermal coefficients are nearly equal (about 12×10⁻⁶ per °C), bond is good and concrete protects steel from corrosion and fire
4. D.Under-reinforced section — a slab spans one way when the longer-to-shorter span ratio exceeds 2; below 2 it bends in both directions and is designed as two-way

Answer + AI explanation with Pro

1. A.section in which concrete reaches its limiting strain of 0.0035 at the same instant that tension steel reaches its yield strain
2. B.xu,max/d is 0.53 for Fe250, 0.48 for Fe415 and 0.46 for Fe500, the cap that keeps a section from becoming over-reinforced
3. C.concrete compression is parabolic-rectangular with peak stress 0.446 fck, total force 0.36 fck b xu acting 0.42 xu below the compression face
4. D.concrete crushes before steel yields, producing a sudden brittle failure without warning, so limit state design prohibits it

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1. A.Over-reinforced section
2. B.Limiting neutral axis depth
3. C.Characteristic strength
4. D.Balanced section

Answer + AI explanation with Pro

1. A.Over-reinforced section — xu,max/d is 0.53 for Fe250, 0.48 for Fe415 and 0.46 for Fe500, the cap that keeps a section from becoming over-reinforced
2. B.Over-reinforced section — concrete compression is parabolic-rectangular with peak stress 0.446 fck, total force 0.36 fck b xu acting 0.42 xu below the compression face
3. C.Over-reinforced section — concrete crushes before steel yields, producing a sudden brittle failure without warning, so limit state design prohibits it
4. D.Over-reinforced section — the two materials act together because their thermal coefficients are nearly equal (about 12×10⁻⁶ per °C), bond is good and concrete protects steel from corrosion and fire

Answer + AI explanation with Pro

1. A.concrete compression is parabolic-rectangular with peak stress 0.446 fck, total force 0.36 fck b xu acting 0.42 xu below the compression face
2. B.a slab spans one way when the longer-to-shorter span ratio exceeds 2; below 2 it bends in both directions and is designed as two-way
3. C.xu,max/d is 0.53 for Fe250, 0.48 for Fe415 and 0.46 for Fe500, the cap that keeps a section from becoming over-reinforced
4. D.steel yields before concrete crushes, giving large deflection and visible cracking as warning, which is why codes require this failure mode

Answer + AI explanation with Pro

1. A.Steel–concrete compatibility
2. B.Limiting moment of resistance
3. C.Limiting neutral axis depth
4. D.Under-reinforced section

Answer + AI explanation with Pro

1. A.Limiting neutral axis depth — steel yields before concrete crushes, giving large deflection and visible cracking as warning, which is why codes require this failure mode
2. B.Limiting neutral axis depth — xu,max/d is 0.53 for Fe250, 0.48 for Fe415 and 0.46 for Fe500, the cap that keeps a section from becoming over-reinforced
3. C.Limiting neutral axis depth — a slab spans one way when the longer-to-shorter span ratio exceeds 2; below 2 it bends in both directions and is designed as two-way
4. D.Limiting neutral axis depth — the two materials act together because their thermal coefficients are nearly equal (about 12×10⁻⁶ per °C), bond is good and concrete protects steel from corrosion and fire

Answer + AI explanation with Pro

1. A.section in which concrete reaches its limiting strain of 0.0035 at the same instant that tension steel reaches its yield strain
2. B.a slab spans one way when the longer-to-shorter span ratio exceeds 2; below 2 it bends in both directions and is designed as two-way
3. C.Mu,lim = 0.36 fck b xu,max (d − 0.42 xu,max), the largest moment a singly reinforced section can carry under limit state
4. D.xu,max/d is 0.53 for Fe250, 0.48 for Fe415 and 0.46 for Fe500, the cap that keeps a section from becoming over-reinforced

Answer + AI explanation with Pro

1. A.Limit state stress block
2. B.Limiting neutral axis depth
3. C.Limiting moment of resistance
4. D.Doubly reinforced beam

Answer + AI explanation with Pro

1. A.Limiting moment of resistance — a slab spans one way when the longer-to-shorter span ratio exceeds 2; below 2 it bends in both directions and is designed as two-way
2. B.Limiting moment of resistance — Mu,lim = 0.36 fck b xu,max (d − 0.42 xu,max), the largest moment a singly reinforced section can carry under limit state
3. C.Limiting moment of resistance — concrete compression is parabolic-rectangular with peak stress 0.446 fck, total force 0.36 fck b xu acting 0.42 xu below the compression face
4. D.Limiting moment of resistance — the two materials act together because their thermal coefficients are nearly equal (about 12×10⁻⁶ per °C), bond is good and concrete protects steel from corrosion and fire

Answer + AI explanation with Pro

1. A.compression steel is added when the factored moment exceeds the limiting moment and the section depth is restricted by headroom or architecture
2. B.strength below which not more than 5 percent of test results are expected to fall, so M25 means a 28-day cube strength of 25 N/mm²
3. C.the two materials act together because their thermal coefficients are nearly equal (about 12×10⁻⁶ per °C), bond is good and concrete protects steel from corrosion and fire
4. D.section in which concrete reaches its limiting strain of 0.0035 at the same instant that tension steel reaches its yield strain

Answer + AI explanation with Pro

1. A.Steel–concrete compatibility
2. B.Balanced section
3. C.Doubly reinforced beam
4. D.Under-reinforced section

Answer + AI explanation with Pro

1. A.Doubly reinforced beam — concrete compression is parabolic-rectangular with peak stress 0.446 fck, total force 0.36 fck b xu acting 0.42 xu below the compression face
2. B.Doubly reinforced beam — section in which concrete reaches its limiting strain of 0.0035 at the same instant that tension steel reaches its yield strain
3. C.Doubly reinforced beam — Mu,lim = 0.36 fck b xu,max (d − 0.42 xu,max), the largest moment a singly reinforced section can carry under limit state
4. D.Doubly reinforced beam — compression steel is added when the factored moment exceeds the limiting moment and the section depth is restricted by headroom or architecture

Answer + AI explanation with Pro

1. A.a slab spans one way when the longer-to-shorter span ratio exceeds 2; below 2 it bends in both directions and is designed as two-way
2. B.concrete compression is parabolic-rectangular with peak stress 0.446 fck, total force 0.36 fck b xu acting 0.42 xu below the compression face
3. C.concrete crushes before steel yields, producing a sudden brittle failure without warning, so limit state design prohibits it
4. D.xu,max/d is 0.53 for Fe250, 0.48 for Fe415 and 0.46 for Fe500, the cap that keeps a section from becoming over-reinforced

Answer + AI explanation with Pro

1. A.Under-reinforced section
2. B.Over-reinforced section
3. C.Limit state stress block
4. D.Balanced section

Answer + AI explanation with Pro

1. A.Limit state stress block — concrete compression is parabolic-rectangular with peak stress 0.446 fck, total force 0.36 fck b xu acting 0.42 xu below the compression face
2. B.Limit state stress block — the two materials act together because their thermal coefficients are nearly equal (about 12×10⁻⁶ per °C), bond is good and concrete protects steel from corrosion and fire
3. C.Limit state stress block — section in which concrete reaches its limiting strain of 0.0035 at the same instant that tension steel reaches its yield strain
4. D.Limit state stress block — xu,max/d is 0.53 for Fe250, 0.48 for Fe415 and 0.46 for Fe500, the cap that keeps a section from becoming over-reinforced

Answer + AI explanation with Pro