12
Total Columns
300
Size (mm²)
4T16
Main Bars
+2T12
Extra Mid Bars
T8@150
Stirrups
G+1
Floors
Cross-Section Details — GF & FF Columns
Sheet 1 of 4
Column 300×300mm · Section at mid-height · All dimensions in mm · Scale NTS
GF Column — Section AA
300×300 · 4T16 + 2T12 · T8@150 · COVER 40mmFF Column — Section BB
300×300 · 4T12 · T8@150 · COVER 40mm · REDUCED STEELColumn Reinforcement Schedule
GF vs FF COMPARISON| Parameter | GF Column | FF Column |
|---|---|---|
| Section | 300×300mm | 300×300mm |
| Concrete | M20 | M20 |
| Steel Grade | Fe500 | Fe500 |
| Main Bars | 4T16 + 2T12 | 4T12 |
| No. of Bars | 6 bars | 4 bars |
| Stirrups | T8 @150 | T8 @150 |
| Stirrup Zone | @100 (L/6 zones) | @150 |
| Clear Cover | 40mm | 40mm |
| Floor Ht. | 3000mm | 3000mm |
| Clear Ht. | ~2550mm | ~2550mm |
| p% (steel) | 1.34% | 0.75% |
| Min p% | 0.8% ✔ | 0.8% ✔ |
Steel Ratio Check
GF: (4×201 + 2×113)/(300×300) = 1.34% ✔ (0.8–4%)
FF: (4×113)/(300×300) = 0.75% → use 0.8% min
→ Increase FF to 4T12 + 2T10 to meet min p%
Confining Zone (IS 13920)
Stirrups @100mm in L/6 at top & bottom
(= 500mm zone each end of column)
GF: (4×201 + 2×113)/(300×300) = 1.34% ✔ (0.8–4%)
FF: (4×113)/(300×300) = 0.75% → use 0.8% min
→ Increase FF to 4T12 + 2T10 to meet min p%
Confining Zone (IS 13920)
Stirrups @100mm in L/6 at top & bottom
(= 500mm zone each end of column)
Column Elevation — Full Height Reinforcement
Sheet 2 of 4
Vertical section showing GF + FF column with lap zone, stirrup spacing, and beam connections
Column Elevation — GF to FF (Section C–C)
TOTAL HEIGHT: FOOTING TO ROOF · LAP, STIRRUP ZONES, BEAM CONNECTION SHOWNStirrup Detail (T8)
135° HOOK · IS 456
Stirrup Zones (IS 13920)
· L/6 from beam face = 500mm each end
· Spacing in confine zone: T8@100
· Spacing in middle zone: T8@150
· Hook: 135° with 10d extension
· L/6 from beam face = 500mm each end
· Spacing in confine zone: T8@100
· Spacing in middle zone: T8@150
· Hook: 135° with 10d extension
Lap Splice Detail
AT FLOOR LEVEL · 800mm LAPBar Bending Schedule & Engineering Notes
Sheet 3 of 4
Complete bar schedule for all 12 columns · GF + FF combined · All lengths in mm
Bar Bending Schedule — Columns
12 COLUMNS TOTAL · GF + FF| Bar | Dia | Floor | Shape | Length/Bar | Nos/Col | Total Nos | Total Length |
|---|---|---|---|---|---|---|---|
| M1 | T16 | GF (×8 cols) | Straight+Hook | 3900mm | 4 | 32 | 124.8 m |
| M2 | T12 | GF (×8 cols) | Straight+Hook | 3900mm | 2 | 16 | 62.4 m |
| M3 | T16 | GF B-Spine (×4) | Straight+Hook | 3900mm | 4 | 16 | 62.4 m |
| M4 | T12 | GF B-Spine (×4) | Straight+Hook | 3900mm | 2 | 8 | 31.2 m |
| M5 | T12 | FF (all ×12) | Straight+Hook | 3900mm | 4 | 48 | 187.2 m |
| S1 | T8 | GF — confine | Rect. 220×220 | 1020mm | 10/end×2 | 240 | 244.8 m |
| S2 | T8 | GF — normal | Rect. 220×220 | 1020mm | 13/col | 156 | 159.1 m |
| S3 | T8 | FF — all | Rect. 220×220 | 1020mm | 20/col | 240 | 244.8 m |
GF Steel Summary
T16 bars: 280.8m → ~445 kg
T12 bars: 93.6m → ~83 kg
T8 stirrups: 403.9m → ~159 kg
GF Total: ~687 kg
T12 bars: 93.6m → ~83 kg
T8 stirrups: 403.9m → ~159 kg
GF Total: ~687 kg
FF Steel Summary
T12 bars: 187.2m → ~166 kg
T8 stirrups: 244.8m → ~97 kg
FF Total: ~263 kg
T8 stirrups: 244.8m → ~97 kg
FF Total: ~263 kg
Column Specification Summary
BOTH FLOORS| Parameter | Specification |
|---|---|
| Column Size | 300 × 300 mm (both floors) |
| GF Main Steel | 4T16 + 2T12 (6 bars) |
| FF Main Steel | 4T12 (4 bars) |
| Stirrups | T8 @ 150mm (normal) |
| Confine Stirrups | T8 @ 100mm (L/6=500mm) |
| Concrete (GF) | M20 (fck=20 N/mm²) |
| Concrete (FF) | M20 |
| Steel Grade | Fe500 HYSD (IS 1786) |
| Clear Cover | 40mm (moderate exposure) |
| Lap Length | 800mm (50d for T16) |
| Lap Position | 500mm above beam top |
| Floor Height | 3000mm (both floors) |
| Effective Ht. | 2550mm (after beam depths) |
| Slenderness | 2550/300 = 8.5 < 12 ✔ |
| Min. p% | 0.8% (IS 456:2000) |
| Future G+2 | Increase GF to 4T20 if needed |
Engineering Notes
IS 456 · IS 13920 COMPLIANCE
Main Bars
· GF: 4T16 corner + 2T12 mid = p%=1.34% ✔
· FF: 4T12 = p%=0.75% → add 2T10 for p%≥0.8%
· Starter bars: extend 800mm above footing
· Lap at 500mm above beam top level
· Stagger laps — not all bars at same level
Stirrups (IS 13920 Ductile)
· Confine zone = L/6 = 500mm each end
· @100mm in confine zone, @150 elsewhere
· 135° hooks with 10d extension
· First stirrup: 50mm from beam/footing face
Concrete
· Use M20 throughout — do not reduce
· Water-cement ratio ≤ 0.50
· Compact with needle vibrator
· Curing: min. 14 days wet curing
Construction
· Clean column cage before pouring beam
· Keep vertical tolerance ≤ H/500
· No horizontal bars inside stirrups
· Shuttering: plumb ± 3mm per 3m height
· GF: 4T16 corner + 2T12 mid = p%=1.34% ✔
· FF: 4T12 = p%=0.75% → add 2T10 for p%≥0.8%
· Starter bars: extend 800mm above footing
· Lap at 500mm above beam top level
· Stagger laps — not all bars at same level
Stirrups (IS 13920 Ductile)
· Confine zone = L/6 = 500mm each end
· @100mm in confine zone, @150 elsewhere
· 135° hooks with 10d extension
· First stirrup: 50mm from beam/footing face
Concrete
· Use M20 throughout — do not reduce
· Water-cement ratio ≤ 0.50
· Compact with needle vibrator
· Curing: min. 14 days wet curing
Construction
· Clean column cage before pouring beam
· Keep vertical tolerance ≤ H/500
· No horizontal bars inside stirrups
· Shuttering: plumb ± 3mm per 3m height