Earth Pressure Coefficients Calculator (Ka, Kp, K0)
Active, passive and at-rest coefficients from friction angle.
ฯ=30ยฐ gives the famous 1/3 โ 0.5 โ 3 trio. The wall must MOVE to mobilize them: ~0.1โ0.4% of height for active, 10ร more for full passive โ basement walls that can't move design for Kโ.
Formula
Earth Pressure Coefficients Calculator (Ka, Kp, K0) is a free ka kp k0 for geotechnical engineers and foundation designers โ instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Earth Pressure Coefficients Calculator (Ka, Kp, K0)
Active, passive and at-rest coefficients from friction angle. The calculation implements K_a = tanยฒ(45โฯ/2); K_p = 1/K_a; Kโ = 1โsinฯ (Jaky) (Rankine (1857); Jaky (1944)). ฯ=30ยฐ gives the famous 1/3 โ 0.5 โ 3 trio. The wall must MOVE to mobilize them: ~0.1โ0.4% of height for active, 10ร more for full passive โ basement walls that can't move design for Kโ.
How to use Earth Pressure Coefficients Calculator (Ka, Kp, K0)
- 1Enter Friction angle ฯ in ยฐ.
- 2Read Active K_a, Passive K_p, At-rest Kโ (1โsinฯ) instantly โ no submit button needed.
Why use Earth Pressure Coefficients Calculator (Ka, Kp, K0)?
- โImplements the standard formula โ K_a = tanยฒ(45โฯ/2); K_p = 1/K_a; Kโ = 1โsinฯ (Jaky)
- โReference cited on-page: Rankine (1857); Jaky (1944)
- โLive worked example: the substitution recomputes from your numbers
- โRuns entirely in your browser โ nothing uploaded, free forever
Frequently asked questions
What formula does the Earth Pressure Coefficients Calculator (Ka, Kp, K0) use?+
It computes K_a = tanยฒ(45โฯ/2); K_p = 1/K_a; Kโ = 1โsinฯ (Jaky), per Rankine (1857); Jaky (1944). The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
ฯ=30ยฐ gives the famous 1/3 โ 0.5 โ 3 trio. The wall must MOVE to mobilize them: ~0.1โ0.4% of height for active, 10ร more for full passive โ basement walls that can't move design for Kโ.
Can this replace a soil investigation?+
No calculator replaces boreholes and lab tests โ but with investigated parameters in hand, this gives you the standard-method result instantly, with the formula shown so reviewers can check it.
Is the Earth Pressure Coefficients Calculator (Ka, Kp, K0) free to use?+
Yes โ completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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