Foundations & Piles
Seismic Site Classification & Response Spectrum
Determine seismic Site Class (ASCE 7-16/22 & Eurocode 8) from 30m weighted average Vs30, N60, and su with live Design Acceleration Response Spectrum curves (Sa vs. T).
Seismic Site Classification & Response Spectrum
Determine seismic Site Class (ASCE 7-16/22 & Eurocode 8) from 30m weighted average Vs30, N60, and su with live Design Acceleration Response Spectrum curves (Sa vs. T).
Inputs
1. Subsurface Profile (Top 30 m)
| Layer Description | Thick di (m) | Vs (m/s) | N60 | su (kPa) | |
|---|---|---|---|---|---|
2. Seismic Ground Motion Parameters
Theory and formulae
Theory & Formulae
About this calculator
This free seismic site classification calculator runs entirely in your browser: what you enter is never uploaded. 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: ASCE 7-16/7-22, IBC 2024, Eurocode 8 (EN 1998-1).
Topics: seismic, site class, response spectrum, vs30, asce 7, eurocode 8, earthquake, spt n60, spectral acceleration, fa fv.
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.
Open this calculator online: geotechnica.ca/tools/seismic-site-classification
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