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Under-Reamed Pile Generator

IS 2911 (Part 3):1980 — DXF + PDF output
Shaft Diameter (Du)
mm — standard sizes per IS 2911 Pt 3 Table 1
Bulb Diameter (Db)
Auto: 2.5 × Du = 937.5 mm. Untick Customise above to override.
Pile Length Below GL
mm — range 3500 – 30000 (IS 2911 Pt 3 Cl. 4.2.3)
Number of Bulbs
First Bulb Depth (below GL)
mm — range 1500 – 3331.25
Main Reinforcement
Bar count
Bar Ø (mm)
Auto per IS 2911 Pt 3 Table 1. Untick Customise to override.
Stirrups (Shaft)
Stirrup Ø (mm)
c/c spacing (mm)
Auto: Ø6 @ 250 mm c/c. Untick Customise to override.
Cover
Auto: 50 mm per IS 2911 Pt 1. Untick Customise to override.
Materials
Concrete
Steel
DXF for CAD edit • PDF for printing / quick share
Live Preview — Elevation
GROUND LEVELL = 4200 mm3000 mmØ 937.5 (Db)Ø 375 (Du)4 – Ø12 long.Ø6 stirrups @ 250 c/c
Preview shows live geometry. PDF download adds full sheet layout — title block, BBS table, legend, notes per IS 696 / SP 46:2003.
Quick Reference — IS 2911 (Part 3):1980
Min shaft Ø200 mm
Bulb Ø range2 – 3 × Du (typical 2.5 ×)
Min pile length3.5 m
First bulb depth (below GL)≥ 1.5 m
Bulb c/c (two-bulb)≥ 1.25 × Db
Cover50 – 75 mm
Stirrup spiral around bulbØ8 mm @ 150 mm pitch
Full code reference: IS 2911 (Part 3):1980 →