Damages Analysis#

💥 What happens to infrastructure when a hazard strikes?#

The Damages module in RA2CE estimates the physical (direct) damage to infrastructure caused by natural hazards such as floods, cyclones, or earthquakes. This provides a critical step in risk assessment: quantifying how exposed assets will be affected when hazard intensities exceed certain thresholds.

Two main types of questions can be addressed:

Event-based damages – What is the expected physical damage to my infrastructure for a specific hazard event?
Risk-based damages – What is the **Expected Annual Damage (EAD)* to my infrastructure, based on hazard probability distributions?*

RA2CE supports both workflows through a combination of damage curves and hazard layers.

How RA2CE Calculates Damage#

The basic workflow for calculating physical damage is:

Hazard input – A spatial layer (e.g., flood depth, wind speed, PGA) is provided for a specific event or set of events.
Asset data – Infrastructure elements (e.g., roads, buildings, facilities) are represented as network components or spatial layers.
Damage curves – Functions that map hazard intensity to expected damage (from 0% = no damage to 100% = full destruction).
Overlay and calculation – For each asset, RA2CE looks up the hazard intensity, applies the appropriate damage curve, and computes the damage fraction and cost.
Aggregation – Results can be summarized per asset, per category, or across the entire network. Risk-based analyses additionally integrate across probability distributions to compute EAD.

Types of Damage Curves#

RA2CE offers several ways to represent the hazard–damage relationship:

Reference damage curves Built-in functions from literature or past studies. Examples: Huizinga global flood curves (HZ), OSdaMage European functions (OSD).
Manual damage curves User-defined curves tailored to site-specific infrastructure, historical data, or alternative vulnerability scenarios.

Which option to choose?

Reference curves – Fast and consistent for large-scale or exploratory analysis.
Manual curves – Essential when local calibration or specific engineering detail is available.

Expected Annual Damage (EAD)#

While single-event damages are valuable, decision-making often requires a risk perspective. RA2CE therefore supports the computation of Expected Annual Damage (EAD):

Hazard scenarios are combined with their annual exceedance probabilities (AEP).
Damages across events are aggregated to obtain the long-term average expected damage.
EAD provides a measure of risk that can be compared across assets, regions, or investment strategies.

This is especially useful for cost–benefit analyses, adaptation planning, and prioritizing investments in resilience.

Where to Start#

The following tutorials guide you through different parts of the damages workflow: