End-to-end Simulation and Analysis Framework for Efficient Seismic Retrofitting of Water Systems

Maintaining the functionality, productivity, and safety of communities necessitates the seismic reliability of lifeline infrastructure networks. However, assessing the reliability of an infrastructure network is a nontrivial task due to the variability of ground motion and the complexity of the response of the network resulting from that ground motion. Even more challenging is the task of identifying retrofit schemes that effectively and efficiently bolster the reliability of the network. Previous works have studied hazard identification, network reliability estimation, and network retrofitting, though somewhat independently. This paper extends and unifies previous work on these topics by establishing an end-to-end simulation and analysis framework that encompasses ground motion simulation, network component fragility, network modeling, and retrofit prioritization. By utilizing a full probabilistic description of the seismic hazard and integrating earthquake occurrence rates into the retrofit evaluation scheme, this framework not only identifies critical network components, but those critical components that are also likely to be damaged. A case study of the Auxiliary Water Supply System of San Francisco is used to demonstrate the procedure described in the proposed framework. This paper shows that this framework contributes retrofitting heuristics that inform existing methods of pipe retrofitting prioritization such that more effective retrofits are obtained.