D1.8 – Recommended Models for Landslide Triggering and Runout in Quantitative Risk Assessment

SafeLand FP7 Deliverable Archive – Modelling Guidelines for Hazard Assessment

Deliverable D1.8 of the SafeLand FP7 project provides guidance on selecting suitable models for landslide triggering and propagation analysis within Quantitative Risk Assessment (QRA) frameworks.

The document was coordinated with contributions from the AMRA – Analysis and Monitoring of Environmental Risk research center and other European research partners.


Main Objective

The main goal of D1.8 is to support model selection for rainfall- and earthquake-induced landslides across multiple spatial scales.

The guidelines aim to balance computational complexity, physical accuracy, and operational applicability in hazard and risk management.


Triggering Mechanism Modelling Approaches

Rainfall-Induced Landslides

  • SHALSTAB steady-state hydrological stability modelling
  • TRIGRS transient infiltration modelling using Richards equation
  • I-MOD3D basin-scale precipitation response simulation

Infinite slope stability assumptions are generally used for regional susceptibility screening.

Earthquake-Induced Landslides

  • Pseudo-static stability analysis using seismic coefficients
  • Newmark displacement rigid-block integration
  • Coupled stick-slip dynamic response modelling

Typical seismic analysis parameters include PGA-based acceleration ratios and critical yield acceleration thresholds.


Runout Propagation Modelling

Two principal modelling strategies are recommended.

Empirical Approaches

  • Angle-of-reach mobility estimation
  • Volume-distance scaling relationships
  • Historical event back-analysis

Numerical Simulation Approaches

  • DAN-family block and depth-integrated models
  • Voellmy friction-turbulence flow formulation
  • Bingham and viscoplastic continuum flow models
  • SPH particle-based simulation methods

Influencing Geological and Environmental Factors

Geological Controls

  • Soil type and consolidation history
  • Stratigraphic structure
  • Cohesion and suction effects
  • Rock mass discontinuities

Hydrological Controls

  • Vertical infiltration modelling
  • Antecedent moisture conditions
  • Evapotranspiration processes
  • Bedrock permeability variation

Scale Effects

  • Regional GIS susceptibility modelling
  • Site-specific finite element simulation
  • DEM resolution sensitivity

Practical Application in Risk Assessment

The document recommends a hierarchical modelling workflow:

  • Regional screening using GIS susceptibility tools
  • Intermediate hazard evaluation using semi-empirical models
  • Detailed site analysis using numerical simulation
  • Calibration using historical event observations

Uncertainty treatment is emphasised through probabilistic analysis and sensitivity evaluation.


Technical Keywords

  • Infinite slope stability
  • Richards infiltration modelling
  • Newmark displacement analysis
  • Pseudo-static seismic stability
  • Quantitative risk assessment (QRA)
  • Empirical runout prediction
  • Unsaturated flow modelling
  • GIS susceptibility mapping
  • Mohr–Coulomb stability criterion
  • Stick–slip dynamic response

Role Within SafeLand Research Framework

Deliverable D1.8 acts as a methodological bridge between hazard mechanism science and operational risk assessment tools.

The guidelines support European landslide risk management by promoting model selection based on scale, data availability, and application objective.


Archive Integration Notes

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Landslide modelling in risk assessment requires balancing physical realism, computational efficiency, and uncertainty management. Model selection should follow application scale and data quality constraints.