Dynamic Simulation of the Probable Propagation of a Disaster in an Engineering System Using a Scenario-Based Hybrid Network Model

With the growing threat of worldwide natural disasters, the safety status of the engineering system is facing serious uncertainties. A small disturbance can cause unexpected serious losses through amplification effects of the fragile environment and unwanted interactions of system elements. The safety status of the disrupted engineering system is subject to profound uncertainty and cognitive ambiguity, which is an impediment to emergency simulation decision making. To analyze the likely future under profound uncertainty, this article develops a scenario-based method to simulate the dynamic evolution process of complex disasters for the engineering system. The complex chain of disasters is segmented into a set of correlated scenarios, and the cascading effects between these scenarios are modeled according to the risk-propagation-consequences process. We applied this method to a mega rail transportation project and established a disaster evolution network in an attempt to traverse all possible future scenarios during operation. The Monte Carlo simulations made it possible to assess the disastrous consequences of the various disturbances and to identify the most vulnerable nodes. This model is expected to reduce uncertainty and provide key information for emergency decision making within the engineering system project.