Course B — Liquefaction Modelling with OpenSees

5 days | For geotechnical engineers in consultancies and research | English

Overview

This course provides a rigorous treatment of liquefaction modelling using OpenSees 3D solid finite elements. It is designed for geotechnical engineers who need to move beyond simplified empirical methods (SPT-based triggering charts) toward physics-based effective stress analysis that captures pore pressure generation, redistribution, and dissipation under cyclic loading. The course combines constitutive model theory with hands-on 3D model building and addresses the HPC requirements of large geotechnical solid models.

Prerequisites

Geotechnical engineering background, basic FEM understanding, Python or MATLAB basics.

Software and Standards

Software: OpenSees (Tcl/Python), OpenSeesMP for parallelisation, Google Cloud Platform for large model runs, ParaView for visualisation

Regulatory context: Eurocode 7/8 for SSI, offshore foundation standards, post-2023 Turkish seismic code

Learning Objectives

Understand effective stress principles and the mechanics of pore pressure generation under cyclic loading
Implement and calibrate cyclic constitutive models for liquefiable sands (PDMY, PIMY, PM4Sand class models)
Build 3D solid FEM models in OpenSees with appropriate boundary conditions and drainage conditions
Apply seismic input motions correctly to soil column and 3D models (compliant base, rigid base, domain reduction)
Interpret pore pressure ratio, settlement, and lateral spreading outputs
Validate models against centrifuge and field case study data
Run large models in parallel using OpenSeesMP on Google Cloud Platform

Daily Schedule

Day	Topics
Day 1	Effective stress framework, Terzaghi consolidation recap, cyclic shear stress ratio, triggering mechanisms. Introduction to OpenSees solid element architecture and u-p formulation.
Day 2	Constitutive models for liquefiable soils: PDMY02, PIMY, and PM4Sand family. Calibration strategy from laboratory data. Hands-on model calibration exercises.
Day 3	3D soil column model: mesh generation, element assignment, boundary conditions, drainage options, gravity consolidation procedure. Free-field response validation.
Day 4	Full 3D liquefaction model: lateral spreading, structure-soil interaction, pore pressure redistribution. Seismic input application methods. Result extraction and visualisation with ParaView.
Day 5	Case studies: centrifuge test validation, field performance case history. HPC deployment: compiling OpenSeesMP, mesh partitioning with METIS, running on GCP, cost management.