Multi-Hazard Community Resilience Analysis Using Earthquake-Tsunami Fragility Surfaces: Damage and Economic Loss Assessment in the Pseudo Seaside Testbed

This simulation investigates community-level resilience under earthquake-tsunami multi-hazard scenarios using 3D fragility surfaces. The study applies a Monte Carlo simulation framework to the Pseudo Seaside testbed, a synthetic coastal community model based on Seaside, Oregon, to analyze structural damage, economic loss, and the effectiveness of resilience strategies.

Methodology:

- Fragility Surface Application: The earthquake-tsunami fragility surfaces were used to estimate damage probabilities for different building archetypes, including reinforced concrete (RC) and woodframe structures.

- Monte Carlo Simulation: A high-resolution Monte Carlo approach was employed to model structural failure distributions across various seismic intensities and tsunami inundation depths.

- Comparison of Methodologies: The FEMA combinational rule was assessed alongside the newly developed fragility surface-based approach to evaluate cumulative damage and economic losses.

- Economic Loss Estimation: The direct loss estimation framework integrates replacement cost assessments with probabilistic damage distributions, providing a quantitative measure of resilience.

Key Findings:

- Multi-hazard fragility surfaces provide a more accurate representation of earthquake-tsunami damage than traditional -- - FEMA combinational rules, particularly at higher hazard intensities.
- Economic loss estimations indicate a significant underprediction of damage using independent hazard models, emphasizing the need for integrated multi-hazard analysis.
- The methodology reduces computational time by approximately threefold compared to separate earthquake and tsunami simulations, improving computational efficiency for large-scale community resilience assessments.
- Pseudo Seaside testbed results highlight the necessity of multi-hazard resilience planning, especially for coastal communities at risk of Cascadia Subduction Zone (CSZ) events.

Reusability of Data:
This dataset and simulation framework can be reused for:

- Multi-hazard community resilience studies for other coastal regions.
- Integration into platforms such as IN-CORE for resilience decision-making.
- Calibrating structural fragility functions for earthquake and tsunami hazards.
- Urban planning and mitigation strategy design for disaster risk reduction.
- Benchmarking multi-hazard loss assessment methodologies against FEMA statistical approaches.

The simulation is published on DesignSafe to facilitate open-access collaboration and further advancements in multi-hazard resilience modeling.