Consequence Models
Introduction
Consequence models translate structural damage states into economic losses and other impact metrics. These models are essential for converting fragility analysis results into actionable risk metrics for decision-making.
Damage-to-Loss Ratios
Damage-to-loss ratios map each damage state to an expected loss expressed as a fraction of a building’s replacement cost. The ratios used in this model are:
Damage State |
Mean Ratio |
Description |
|---|---|---|
DS1 (Slight) |
0.05 |
Minor cosmetic repairs |
DS2 (Moderate) |
0.15 |
Moderate structural repairs |
DS3 (Extensive) |
0.60 |
Major structural repairs |
DS4 (Complete) |
1.00 |
Full replacement |
Sources and Derivation
The damage-to-loss ratios are derived from:
- Empirical Data
Post-earthquake damage and repair cost surveys (Di Pasquale et al. 2005; Bal et al. 2008)
- Analytical Procedures
Component-based loss estimation methodologies (Martins et al. 2016; Aljawhari et al. 2023)
Loss Categories
Structural Losses
Losses associated with damage to the building’s lateral load-resisting system and gravity load-carrying elements.
Non-Structural Loss Functions (SLFs)
Storey Loss Functions (SLFs) relate engineering demand parameters (EDPs) directly to loss ratios for non-structural components. Two types of SLFs are provided:
Drift-sensitive SLFs: For components sensitive to interstorey drift (partitions, facades, stairs)
Acceleration-sensitive SLFs: For components sensitive to floor acceleration (ceilings, MEP systems)
The SLFs are available for different regions, building materials, component categories, and occupancy types.
Interactive SLF Viewer
Embodied Carbon Loss Functions
Carbon SLFs express embodied carbon loss (kg CO₂-eq per unit floor area) as a function of EDP, for structural and non-structural components. They follow the same region × material × component × occupancy structure as the non-structural SLFs above.
Interactive Carbon SLF Viewer
Contents Losses
Losses from damage to building contents including furniture, fixtures, equipment, machinery, personal belongings (residential), and inventory (commercial/industrial).
Casualty Consequence Models
Casualty models estimate fatalities and injuries based on building damage and collapse. The consequence ratios below represent the expected proportion of building occupants affected at each damage state.
Fatalities Consequence Ratios
Loading fatalities data...
Injuries Consequence Ratios
Loading injuries data...
Affected Population
Loading affected population data...
Displaced Population
Loading displaced population data...
Regional Variations
Consequence models may vary by region due to:
Construction costs: Labour and material costs differ globally
Repair practices: Different repair approaches for similar damage
Economic factors: Currency, inflation, and market conditions
Building standards: Code requirements for repairs/retrofits
Uncertainty Quantification
Uncertainty in damage-to-loss ratios is captured through:
- Within-Damage-State Variability
Coefficient of variation for loss ratio given each damage state
- Between-Building Variability
Differences in repair costs for buildings of the same class
The uncertainty is propagated through the vulnerability calculation using the formulations described in the Vulnerability Models section.
References
Di Pasquale G. et al. (2005). New developments in seismic risk assessment in Italy. Bulletin of Earthquake Engineering.
Bal I.E. et al. (2008). Detailed assessment of structural characteristics of Turkish RC building stock for loss assessment models. Soil Dynamics and Earthquake Engineering.
Martins L. et al. (2016). Development and assessment of damage-to-loss models for moment-frame reinforced concrete buildings. Earthquake Engineering & Structural Dynamics.
Aljawhari K. et al. (2023). Simulation-based consequence models of seismic direct loss and repair time for archetype reinforced concrete frames. Soil Dynamics and Earthquake Engineering.
FEMA (2012). Next-Generation Methodology for Seismic Performance Assessment of Buildings (FEMA P-58). Washington, D.C.