Retaining & Earth Pressure
Seismic Earth Pressure (Mononobe–Okabe)
Mononobe–Okabe seismic active and passive earth pressure with wall friction, sloping backfill and batter: dynamic increment, resultant height and failure wedge.
Seismic Earth Pressure (Mononobe–Okabe)
Mononobe–Okabe seismic active and passive earth pressure with wall friction, sloping backfill and batter: dynamic increment, resultant height and failure wedge.
Inputs
1. Pressure State & Seismic Coefficients
Usually taken as 0
2. Wall Geometry & Backfill
Commonly φ/2 to 2φ/3
From vertical; negative when the wall back leans into the backfill
Uniform, on the backfill surface
3. Groundwater & Point of Application
Above the base: 0.6 (Seed & Whitman); 1/3 to 2/3 allowed
Results
Enter the seismic coefficient, wall height and backfill strength above, or click a Demo Preset at the top to compute the seismic earth pressure.
Theory and formulae
Mononobe–Okabe Pseudo-Static Theory
About this calculator
This free seismic earth pressure calculator runs entirely in your browser: what you enter is never uploaded. Switch between metric and imperial units at any time. Use the calculation steps and the theory section to check the working, and print a calculation sheet with the inputs, results and formulae for your records.
Methods and references: Mononobe–Okabe (1926, 1929), Seed & Whitman (1970), AASHTO LRFD 11.6.5, Kramer (1996).
Topics: mononobe-okabe, seismic earth pressure, kae, kpe, dynamic increment, seed whitman, pseudo-static, earthquake, retaining wall, horizontal seismic coefficient, kh, pga.
Engineering notice: Results are for preliminary estimation, screening and education. All inputs and outputs must be independently verified by a qualified professional engineer before use in any design or construction decision. Read the full disclaimer
Disclaimer
This calculation sheet was generated with Geotechnical Toolbox for preliminary estimation, screening, educational and verification purposes only. Geotechnical engineering involves site-specific ground conditions and uncertainty. All inputs, methods, results and figures must be independently checked and approved by a qualified Professional Engineer (P.Eng. / PE) before being relied on for design, construction or any safety-critical decision. Results reflect the values entered at the time of printing. The author and site accept no liability for errors, omissions or damages arising from their use.
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