Decision Support Tool for Optimizing Investments to Enhance Seismic Resilience of Transport Networks

The scope of the project was the development of a tool that will be used to strengthen America’s infrastructure (the transportation lifeline systems) by helping prioritize investments that enhance seismic resilience and fulfill strategic functional recovery targets. The tool appraises the resilience impact of alternative investments considering their broader socio-economic benefits and implements advanced multi-parameter optimization algorithms to identify investments that maximize resilience objectives.

To this end, it integrates numerous modules including:
(i) Hazard mapping (by connecting to USGS resources to identify all relevant seismogenic sources that could potentially impact the project location, their intensity and the associated frequency) (ii) Physical vulnerability assessment by incorporating over 200 state-of-the art fragility curves applicable to US highway assets while also allowing user input of relevant data where available
(iii) network modelling to estimate volumes and types of traffic served by the network, as well as the impacts in terms of traffic delays due to detours in case of damage on assets
(iv) economic analysis to assess the value of passenger and freight trips between origins and destinations served by the network
(v) loss analysis to estimate the impact of all plausible scenarios (i.e. by performing thousands of loss analyses) and calculate the annualized average loss along the network
(vi) evaluation of adaptation solutions to estimate the benefits of specific resilience investments by repeating the loss analysis after implementing the relevant retrofitting measures
(vii) optimization of investments Benefit to Cost Ratio (or any selected metric) implementing a powerful genetic algorithm that allows evaluation of thousands of possible investment scenarios bounded by a specific total investment budget, to assess the optimum allocation of resources.

The tool is considered the first of its kind to allow the monetization of resilience investment benefits, which extend far beyond the boundaries of the physical infrastructure itself. The tool predictions have been validated by NIST and the framework is currently under publication as a NIST report to be formally presented to the President’s National Infrastructure Advisory Committee.