Micropile (grout–ground bond + structure) calculator

Inputs in the worked example

The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.

Worked example — results

• ✓ Bond
• ✓ Structure

Method, formulas and assumptions

• Allowable bond π D L α/FS = PI()*200/1000*8*200/2 = 502.65 kN
• Bar area = PI()*40^2/4 = 1256.6 mm²
• Allowable structural 0.4f′c Ag + 0.47fy Ab = (0.4*35*(PI()*200^2/4-1256.6)+0.47*500*1256.6)/1000 = 717.54 kN

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