Development of a comprehensive framework for seismic resilience estimation of urban water transmission networks

Abstract

In recent times, frequent earthquakes have caused human casualties and property damage, resulting in increased social disruption. The critical lifeline infrastructure throughout the city can be directly or indirectly damaged, and it causes significant difficulties in daily life. Therefore, it is important to predict network performance and provide an alternative that minimizes the damage by considering the factors affecting lifeline structures. In view of the above, this study proposes flow-based probabilistic seismic reliability assessment of interdependent urban water transmission network for enhancing seismic resilience. First, this study dealt with a probabilistic reliability approach for post-hazard flow analysis of a water transmission according to earthquake magnitude, pipeline deterioration, and interdependency between pumping plants and 154 kV substations. The model is composed of the following three phases: (1) generation of input ground motion considering spatial correlation, (2) updating the revised nodal demands, and (3) calculation of available nodal demands. Accordingly, a computer code was developed to perform the hydraulic analysis and numerical modeling of water facilities. Second, an optimal system design for the seismic performance enhancement of a water transmission network was proposed. The main purpose of the optimal design is to maximize the system performance within a limited construction cost. The proposed model evaluates network performance through the spatially correlated seismic attenuation law, determination of the failure status of the network facility, and numerical modeling of water networks. For hydraulic simulation, a MATLAB computer code was developed to enable the EPANET program with pressure-driven analysis. Finally, seismic resilience of water transmission network is estimated to measure the recovery time and economical damage. The proposed resilience estimation model includes the spatially correlated ground motion prediction equation and the hydraulic analysis phases, and enables direct and indirect damage prediction based on seismic scenarios. So far, the proposed flow-based seismic reliability model in this study has the advantage of maximizing the resilience of the water transmission network. The results of this study can be used for strategic plans to improve seismic resilience and decision modeling for disaster recovery and recovery strategies in a water transmission network.