Loads & Seismic (IS 875 / IS 1893 / IS 13920) interview questions

1. A.Ta = 0.075 h^0.75 for bare RC moment frames, 0.085 h^0.75 for steel frames and 0.09 h/√d for buildings with masonry infill or shear walls
2. B.IS 875 Part 2 gives 2 kN/m² for residential rooms, 3 for residential stairs and corridors, 2.5 to 4 for offices and 1.5 for accessible roofs
3. C.Ah = (Z/2)(I/R)(Sa/g), multiplied by seismic weight W to give the design base shear VB distributed up the height in proportion to Wi hi²
4. D.1.5 for hospitals, schools, fire stations and other lifeline buildings, 1.2 for residential or commercial buildings housing over 200 people, and 1.0 otherwise

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1. A.Empirical fundamental period
2. B.Soft storey
3. C.Imposed floor loads
4. D.Response reduction factor R

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1. A.Imposed floor loads — 0.10 for zone II, 0.16 for zone III, 0.24 for zone IV and 0.36 for zone V, the old zone I having been merged into zone II
2. B.Imposed floor loads — IS 875 Part 2 gives 2 kN/m² for residential rooms, 3 for residential stairs and corridors, 2.5 to 4 for offices and 1.5 for accessible roofs
3. C.Imposed floor loads — pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones
4. D.Imposed floor loads — storey whose lateral stiffness is less than that of the storey above, typically open stilt parking, which the 2016 code makes a stiffness irregularity requiring explicit analysis rather than a 2.5 force multiplier

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1. A.Ta = 0.075 h^0.75 for bare RC moment frames, 0.085 h^0.75 for steel frames and 0.09 h/√d for buildings with masonry infill or shear walls
2. B.pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones
3. C.IS 13920 requires the sum of column flexural capacities at a joint to be at least 1.4 times the sum of the beam capacities so hinges form in beams
4. D.0.10 for zone II, 0.16 for zone III, 0.24 for zone IV and 0.36 for zone V, the old zone I having been merged into zone II

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1. A.Strong column–weak beam rule
2. B.Zone factor Z
3. C.Imposed floor loads
4. D.Design horizontal seismic coefficient

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1. A.Zone factor Z — 0.10 for zone II, 0.16 for zone III, 0.24 for zone IV and 0.36 for zone V, the old zone I having been merged into zone II
2. B.Zone factor Z — IS 13920 requires the sum of column flexural capacities at a joint to be at least 1.4 times the sum of the beam capacities so hinges form in beams
3. C.Zone factor Z — pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones
4. D.Zone factor Z — 1.5 for hospitals, schools, fire stations and other lifeline buildings, 1.2 for residential or commercial buildings housing over 200 people, and 1.0 otherwise

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1. A.pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones
2. B.0.10 for zone II, 0.16 for zone III, 0.24 for zone IV and 0.36 for zone V, the old zone I having been merged into zone II
3. C.Ta = 0.075 h^0.75 for bare RC moment frames, 0.085 h^0.75 for steel frames and 0.09 h/√d for buildings with masonry infill or shear walls
4. D.1.5 for hospitals, schools, fire stations and other lifeline buildings, 1.2 for residential or commercial buildings housing over 200 people, and 1.0 otherwise

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1. A.Zone factor Z
2. B.Design horizontal seismic coefficient
3. C.Design wind pressure
4. D.Importance factor I

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1. A.Importance factor I — pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones
2. B.Importance factor I — 1.5 for hospitals, schools, fire stations and other lifeline buildings, 1.2 for residential or commercial buildings housing over 200 people, and 1.0 otherwise
3. C.Importance factor I — Ta = 0.075 h^0.75 for bare RC moment frames, 0.085 h^0.75 for steel frames and 0.09 h/√d for buildings with masonry infill or shear walls
4. D.Importance factor I — 0.10 for zone II, 0.16 for zone III, 0.24 for zone IV and 0.36 for zone V, the old zone I having been merged into zone II

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1. A.Ah = (Z/2)(I/R)(Sa/g), multiplied by seismic weight W to give the design base shear VB distributed up the height in proportion to Wi hi²
2. B.1.5 for hospitals, schools, fire stations and other lifeline buildings, 1.2 for residential or commercial buildings housing over 200 people, and 1.0 otherwise
3. C.Ta = 0.075 h^0.75 for bare RC moment frames, 0.085 h^0.75 for steel frames and 0.09 h/√d for buildings with masonry infill or shear walls
4. D.ratio by which elastic seismic demand is divided for ductility and overstrength: 3 for an ordinary RC moment frame and 5 for a special frame detailed per IS 13920

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1. A.Response reduction factor R
2. B.Imposed floor loads
3. C.Empirical fundamental period
4. D.Strong column–weak beam rule

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1. A.Response reduction factor R — ratio by which elastic seismic demand is divided for ductility and overstrength: 3 for an ordinary RC moment frame and 5 for a special frame detailed per IS 13920
2. B.Response reduction factor R — 0.10 for zone II, 0.16 for zone III, 0.24 for zone IV and 0.36 for zone V, the old zone I having been merged into zone II
3. C.Response reduction factor R — IS 875 Part 2 gives 2 kN/m² for residential rooms, 3 for residential stairs and corridors, 2.5 to 4 for offices and 1.5 for accessible roofs
4. D.Response reduction factor R — storey whose lateral stiffness is less than that of the storey above, typically open stilt parking, which the 2016 code makes a stiffness irregularity requiring explicit analysis rather than a 2.5 force multiplier

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1. A.Ah = (Z/2)(I/R)(Sa/g), multiplied by seismic weight W to give the design base shear VB distributed up the height in proportion to Wi hi²
2. B.0.10 for zone II, 0.16 for zone III, 0.24 for zone IV and 0.36 for zone V, the old zone I having been merged into zone II
3. C.IS 13920 requires the sum of column flexural capacities at a joint to be at least 1.4 times the sum of the beam capacities so hinges form in beams
4. D.IS 875 Part 2 gives 2 kN/m² for residential rooms, 3 for residential stairs and corridors, 2.5 to 4 for offices and 1.5 for accessible roofs

Answer + AI explanation with Pro

1. A.Design horizontal seismic coefficient
2. B.Design wind pressure
3. C.Response reduction factor R
4. D.Imposed floor loads

Answer + AI explanation with Pro

1. A.Design horizontal seismic coefficient — IS 875 Part 2 gives 2 kN/m² for residential rooms, 3 for residential stairs and corridors, 2.5 to 4 for offices and 1.5 for accessible roofs
2. B.Design horizontal seismic coefficient — 1.5 for hospitals, schools, fire stations and other lifeline buildings, 1.2 for residential or commercial buildings housing over 200 people, and 1.0 otherwise
3. C.Design horizontal seismic coefficient — pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones
4. D.Design horizontal seismic coefficient — Ah = (Z/2)(I/R)(Sa/g), multiplied by seismic weight W to give the design base shear VB distributed up the height in proportion to Wi hi²

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1. A.pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones
2. B.storey whose lateral stiffness is less than that of the storey above, typically open stilt parking, which the 2016 code makes a stiffness irregularity requiring explicit analysis rather than a 2.5 force multiplier
3. C.Ta = 0.075 h^0.75 for bare RC moment frames, 0.085 h^0.75 for steel frames and 0.09 h/√d for buildings with masonry infill or shear walls
4. D.0.10 for zone II, 0.16 for zone III, 0.24 for zone IV and 0.36 for zone V, the old zone I having been merged into zone II

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1. A.Zone factor Z
2. B.Strong column–weak beam rule
3. C.Response reduction factor R
4. D.Empirical fundamental period

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1. A.Empirical fundamental period — 1.5 for hospitals, schools, fire stations and other lifeline buildings, 1.2 for residential or commercial buildings housing over 200 people, and 1.0 otherwise
2. B.Empirical fundamental period — storey whose lateral stiffness is less than that of the storey above, typically open stilt parking, which the 2016 code makes a stiffness irregularity requiring explicit analysis rather than a 2.5 force multiplier
3. C.Empirical fundamental period — pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones
4. D.Empirical fundamental period — Ta = 0.075 h^0.75 for bare RC moment frames, 0.085 h^0.75 for steel frames and 0.09 h/√d for buildings with masonry infill or shear walls

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1. A.IS 875 Part 2 gives 2 kN/m² for residential rooms, 3 for residential stairs and corridors, 2.5 to 4 for offices and 1.5 for accessible roofs
2. B.pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones
3. C.storey whose lateral stiffness is less than that of the storey above, typically open stilt parking, which the 2016 code makes a stiffness irregularity requiring explicit analysis rather than a 2.5 force multiplier
4. D.Ah = (Z/2)(I/R)(Sa/g), multiplied by seismic weight W to give the design base shear VB distributed up the height in proportion to Wi hi²

Answer + AI explanation with Pro

1. A.Design wind pressure
2. B.Importance factor I
3. C.Design horizontal seismic coefficient
4. D.Response reduction factor R

Answer + AI explanation with Pro

1. A.Design wind pressure — Ah = (Z/2)(I/R)(Sa/g), multiplied by seismic weight W to give the design base shear VB distributed up the height in proportion to Wi hi²
2. B.Design wind pressure — pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones
3. C.Design wind pressure — 0.10 for zone II, 0.16 for zone III, 0.24 for zone IV and 0.36 for zone V, the old zone I having been merged into zone II
4. D.Design wind pressure — 1.5 for hospitals, schools, fire stations and other lifeline buildings, 1.2 for residential or commercial buildings housing over 200 people, and 1.0 otherwise

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1. A.storey whose lateral stiffness is less than that of the storey above, typically open stilt parking, which the 2016 code makes a stiffness irregularity requiring explicit analysis rather than a 2.5 force multiplier
2. B.Ah = (Z/2)(I/R)(Sa/g), multiplied by seismic weight W to give the design base shear VB distributed up the height in proportion to Wi hi²
3. C.IS 875 Part 2 gives 2 kN/m² for residential rooms, 3 for residential stairs and corridors, 2.5 to 4 for offices and 1.5 for accessible roofs
4. D.pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones

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1. A.Imposed floor loads
2. B.Soft storey
3. C.Zone factor Z
4. D.Importance factor I

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1. A.Soft storey — ratio by which elastic seismic demand is divided for ductility and overstrength: 3 for an ordinary RC moment frame and 5 for a special frame detailed per IS 13920
2. B.Soft storey — IS 13920 requires the sum of column flexural capacities at a joint to be at least 1.4 times the sum of the beam capacities so hinges form in beams
3. C.Soft storey — 0.10 for zone II, 0.16 for zone III, 0.24 for zone IV and 0.36 for zone V, the old zone I having been merged into zone II
4. D.Soft storey — storey whose lateral stiffness is less than that of the storey above, typically open stilt parking, which the 2016 code makes a stiffness irregularity requiring explicit analysis rather than a 2.5 force multiplier

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1. A.pz = 0.6 Vz² where Vz = Vb k1 k2 k3 k4, with basic 3-second gust speed at 10 m ranging from 33 to 55 m/s across six wind zones
2. B.1.5 for hospitals, schools, fire stations and other lifeline buildings, 1.2 for residential or commercial buildings housing over 200 people, and 1.0 otherwise
3. C.IS 13920 requires the sum of column flexural capacities at a joint to be at least 1.4 times the sum of the beam capacities so hinges form in beams
4. D.Ta = 0.075 h^0.75 for bare RC moment frames, 0.085 h^0.75 for steel frames and 0.09 h/√d for buildings with masonry infill or shear walls

Answer + AI explanation with Pro

1. A.Design horizontal seismic coefficient
2. B.Zone factor Z
3. C.Importance factor I
4. D.Strong column–weak beam rule

Answer + AI explanation with Pro

1. A.Strong column–weak beam rule — 0.10 for zone II, 0.16 for zone III, 0.24 for zone IV and 0.36 for zone V, the old zone I having been merged into zone II
2. B.Strong column–weak beam rule — IS 13920 requires the sum of column flexural capacities at a joint to be at least 1.4 times the sum of the beam capacities so hinges form in beams
3. C.Strong column–weak beam rule — ratio by which elastic seismic demand is divided for ductility and overstrength: 3 for an ordinary RC moment frame and 5 for a special frame detailed per IS 13920
4. D.Strong column–weak beam rule — IS 875 Part 2 gives 2 kN/m² for residential rooms, 3 for residential stairs and corridors, 2.5 to 4 for offices and 1.5 for accessible roofs

Answer + AI explanation with Pro