Overview
ISO/TR 12930:2014, "Seismic design examples based on ISO 23469", is a technical report that illustrates how to apply ISO 23469:2005 to the seismic design and evaluation of geotechnical works. It provides worked design examples and practical guidance - not new prescriptive rules - intended to help experienced practicing engineers and code writers interpret and use the ISO standard for a wide range of geotechnical structures.
Key topics
The report focuses on the practical steps and technical issues involved in seismic design of geotechnical works, including:
- Two-stage approach to specifying seismic actions:
- First stage: determination of site‑specific earthquake ground motions (empirical, probabilistic and deterministic methods).
- Second stage: seismic evaluation and design of geotechnical works using simplified and detailed analyses.
- Site-specific seismic hazard analysis:
- Probabilistic seismic hazard analysis (PSHA), including evaluation of Fourier amplitude spectra, group delay time and uniform hazard spectra.
- Deterministic and semi‑empirical ground motion estimation, theoretical scenario earthquakes and site amplification assessment.
- Site response and input motion development:
- Procedures to generate ground motion time histories for site response and structural analyses.
- Seismic evaluation methods for geotechnical works:
- Simplified methods (equivalent static, Seismic Deformation Method) and detailed dynamic analyses (FEM/time‑history).
- Assessment of ground displacement, spatial variation of motions, and soil–structure interaction (SSI) effects.
- Liquefaction and ground failure:
- Evaluation techniques and design implications for foundations, retaining walls, dams, tanks and buried structures.
- Illustrative design examples covering buried tunnels, box culverts, pipelines, shallow and deep foundations, diaphragm walls, quay/retaining walls, pile‑supported wharves and piers, earth/rock fill dams, gravity dams, tanks, landfills and waste sites.
Applications
ISO/TR 12930:2014 is practical for:
- Geotechnical and structural engineers performing seismic design or assessment of foundations, retaining walls, tunnels, dams, ports and tanks.
- Design offices preparing site‑specific seismic hazard inputs and ground motion time histories.
- Code developers and regulators seeking worked examples that demonstrate application of ISO 23469 principles.
- Project teams assessing liquefaction risk, ground displacement effects and SSI in seismic regions.
Who should use it
- Experienced practicing engineers, seismic specialists and geotechnical designers.
- Code writers and reviewers looking for example methodologies consistent with ISO 23469.
Related standards
- ISO 23469:2005 - the principal ISO standard on seismic design of geotechnical works on which this TR’s examples are based.
Keywords: seismic design, geotechnical works, ISO/TR 12930, ISO 23469, site‑specific seismic hazard, ground motion, liquefaction, soil‑structure interaction, seismic evaluation, foundation design.
