City-Scale Multi-Infrastructure Network Resilience Simulation Tool

Abstract

The goal of this project is to deliver a coherent framework of simulation tools that can quantify the performance of the water distribution network (WDN) and the transportation network at the city scale under different ground-motion scenarios. In addition to tool development, this project also investigates the potential interactions between structural and infrastructure systems in the case of normal operational and various earthquake damage scenarios. A multi-threaded, high-performance computing (HPC) scalable semi-dynamic traffic simulation model has been developed to understand the complex behaviors of the entire transportation system and to evaluate various performance metrics (e.g., traffic flow, delay, accessibility, etc.) in a large-scale hazard event. An efficient, multi-threaded C++ program, HydrauSim, has been created to understand the hydraulic behavior of WDNs after a disruptive hazard event such as an earthquake. Equipped with advanced linear system solvers, HydrauSim solves hydraulic parameters for a city-scale WDN almost instantaneously, allowing the water distribution change under many earthquake damage scenarios to be determined in a short time. To support a framework of holistic assessment of regional performance after earthquakes, multiple existing tools are integrated, including the ground-motion generation software from Stanford University and the building damage assessment tool rWhale from the SimCenter. Earthquake scenarios (M7.05 Hayward fault) in the San Francisco Bay Area are studied to evaluate the infrastructure networks’ hazard response using the developed tools. In collaboration with the East Bay Municipal Utility District (EBMUD), the WDN hydraulic responses on the EBMUD gravity feed zone (65,700 distribution pipes with a total length of 7,223,217 ft) under various ground movement conditions have been studied. The SimCenter building damage estimation tool, rWhale, is used to simulate building damage states for 1.8 million buildings across the Bay Area. On the traffic side, 2 million agents’ movements on the full San Francisco Bay Area’s road network (224,224 nodes with 549,009 links) has been simulated to understand potential traffic re-distributions after major hazard events. Interactions between these three infrastructure systems under the Hayward fault earthquake scenarios are explored in the study.