| With the dramatic changes in the global climate,the frequency and intensity of extreme natural disaster events are increasing.A series of catastrophic natural disaster events have brought serious blows and major technical accidents to industrial areas around the world.When natural disaster events affect industrial facilities,especially the process equipment that stores or processes large quantities of hazardous substances,they may trigger serious technological failure scenarios,this interlocking process is also called "natural disaster triggered technological accidents"(Natech).Natech events usually lead to catastrophic consequences in a large scale of time and space.Typical examples of Natech events were triggered by the Katrina and Rita hurricanes in 2005,the Wenchuan earthquake in 2008,the Japan earthquake in 2011 and the Hurricane Harvey in 2017.Recently,governments,industry and researchers have begun to focus on the Natech incident and have developed several methods and tools to prevent and mitigate potential Natech incidents.However,the existing studies mainly focus on the Natech triggered by a single disaster,and lack of analysis and research on Natech events triggered by multiple disasters simultaneously.Besides,in the studies on Natech events triggered by some specific natural disasters(earthquake or landslide),most scholars did not consider the cascading events in Natech events,such as the domino effect event,extremely underestimated the serious consequences of the Natech event.In order to solve the problems mentioned above,this paper takes three common natural disasters such as hurricane,earthquake and landslide as examples,the corresponding quantitative risk assessment model and method of Natech event and its domino effect are established according to the characteristics of each natural disaster events.The main contents and research results are as follows:(1)Investigation and statistics of Natech events and correlation analysis of meteorological data based on GIS.The investigation data of damage caused by Hurricane Harvey to onshore chemical facilities were collected by using the official industrial accident database.In view of the incomplete original records,GIS software was used to conduct correlation analysis of the natural disaster factors(maximum flood depth,maximum rainfall intensity and maximum wind speed)of the Natech event.It can provide data basis for quantitative risk analysis of industrial equipment failure during a hurricane.(2)Based on the Bayesian network,the risk assessment method for five failure modes of storage tanks under the multi-disaster coupling condition of strong wind,flood and heavy rainfall was established.Based on the statistical analysis of Natech accidents during Hurricane Harvey,the failure assessment of industrial equipment suffered from multiple disasters during the hurricane was carried out.The storage tank,the most vulnerable industrial equipment during the hurricane,was selected as the research object,and various disaster forms such as strong winds,heavy rains,and floods that the storage tank may encounter during the hurricane were also considered,a method based on physical reliability models and Bayesian Networks(BN)was firstly developed to assess the vulnerability(probability of failure)of industrial equipment to hurricane-induced multiple disasters.By extending the developed BN to the limited memory influence diagram(LIMID),through calculation and analysis,it is concluded that it is feasible measures to reduce the probability of damage to adjust the liquid storage height inside the tank before a hurricane.(3)Based on the Monte Carlo method,a risk assessment framework considering the whole process of Natech events was established by combining the probability model of seismic risk analysis,the vulnerability model of industrial equipment and the evolution model of domino effect.Considering the cascading events and domino scenarios caused by the results of the Natech event,taking the Natech event induced by the earthquake as an example,the risk analysis model and framework of industrial equipment failure caused by the earthquake were established.The risk assessment method of the agent-based model for the Natech and domino effect escalation scenarios triggered by the earthquake was developed,the uncertainty in the Domino accident was considered,the potential propagation path was revealed,and the actual case was verified.For the example in this study,considering the domino effect in the Natech event caused by the earthquake,the overall risk probability increases by about 2 times,indicating that the domino effect cannot be ignored.(4)Landslides are often a kind of secondary disaster induced by earthquakes,but their occurrence time has a certain lag.Therefore,the landslide was considered as a triggering event of a Natech event in this study.Based on the sensitivity analysis of the landslides to earthquakes,the probability of landslide motion and collision as well as the failure probability of the target equipment to the landslide disaster were considered,and the upgrade risk caused by the possible domino effect was modeled and analyzed.A quantitative assessment method for the domino effect was established by using the Agent model,and the actual case was verified. |
