Holding-down bolt or strap allowable stress and minimum cross-sectional area (BS EN 14015:2004, §12)
◉ BS EN 14015:2004 §12 STYLE CHECK · NOT A REGULATORY SUBMISSION TOOL
⚠ Indicative tool only, and genuinely new territory for this project. This is the first EN 14015 content built, and the first general tank anchorage design calculator here — the existing seismic tool only checks anchorage as a consequence of seismic overturning, while this covers the broader set of uplift cases (internal pressure, wind, or their combination) EN 14015 requires anchorage to be checked against. Verified directly against the standard's own page images. Whether anchorage is required at all for your specific tank (§12.1, four listed conditions) is a design judgment this tool doesn't make — it computes the allowable stress and minimum area once you've determined anchorage is needed.
Identification
Research entries stay private to you for practice/testing. Switch to Official once this is a real design your company should see.
When Anchorage Is Required (§12.1, reference)
Anchorage shall be provided if, under any of the following, the shell and adjacent bottom plate may tend to lift off the foundation: (a) uplift of an empty tank from internal design pressure vs. the effective corroded weight of roof, shell, and permanent attachments; (b) internal design pressure combined with wind, vs. that corroded weight plus any product the purchaser specifies as always present; (c) an empty tank under wind alone, vs. the corroded weight; (d) if required by Annex G. When calculating wind uplift, use a minimum wind speed of 45 m/s and a shell shape factor of 0.7.
Holding-Down Bolt or Strap (§12.3)
Allowable stress = the lesser of 0.5×Y or T/3. Minimum cross-sectional area is 500mm² per bolt or strap; if corrosion is anticipated, add 1mm corrosion allowance — 2mm on bolt diameter, or 2mm on strap thickness.
Result
Allowable tensile stress (design condition)—
Minimum cross-sectional area per bolt/strap—
Corrosion allowance to add—
Recommended anchor point spacing: maximum 3m intervals, evenly spaced around the circumference where practical. No initial tension should be applied — the bolt/strap becomes effective only if an uplift force develops.
Resistance to Uplift During Test (§12.4)
The anchorage must also resist uplift from test loads. Under this condition the allowable stress rises to 85% of yield (accounting for any pre-tensioning), rather than the design-condition value above.
Result
Allowable tensile stress (test condition, 85% of Y)—