Method to analyze the regional life loss risk by airborne chemicals released after devastating earthquakes: A simulation approach

Widespread chemical plants render human life more vulnerable to major natural disasters such as earthquakes. Recognizing the potential cascading threats initiated by a devastating earthquake, a general methodology for assessing the life loss risks introduced by airborne hazardous chemical dispersion following seismically induced chemical release (SICR) was proposed. With a 600 km × 600 km region in North China as a demonstrative study area, the dispersion of ammonia released from multiple relevant chemical plants that were supposed to be damaged by a devastating earthquake was simulated in a probabilistic manner. Using an ammonia toxicity-fatality relationship and its toxicity concentration threshold, regional life loss and spatial spread were evaluated. The life loss risk was found to be non-prominent but would be very contingent on unfavorable meteorological conditions. Non-parametric correlation analysis revealed that the respective effects of meteorological mixing parameters on the risk exhibit new features in a disaster context, that is, stronger mixing would cause elevation of risk in a region. This preliminary research implied that the risk of chemical-induced life loss after a devastating earthquake deserves attention and a thorough uncertainty evaluation in the future.     

Seismic damage to pipelines in the framework of Na-Tech risk assessment

The structural integrity of pipelines undergone seismic waves is crucial for industrial installation and for the distributed transportation networks of gaseous and liquid fluids. However, it is nowadays proved that the definition of seismic vulnerability based on purely, structural-derived limit states or on return-to-service or even on the purely economic repair rate indications, is not sufficient for the holistic analysis of risks. On the other hand, detailed numerical studies based on full analyses (including fluid/soil/structure interaction) are too expensive for the aims of risk assessment and simplified methodologies are still needed.In this paper, a large database of earthquake-induced damage for steel and non-steel pipelines is presented. Each case was analyzed and collected from post-earthquake reconnaissance, seismic engineering reports and technical papers. The database may be adopted for the definition of specific vulnerability function (fragility curves), which are commonly implemented in multi-hazard analyses, and more in general for the assessment of Na-Tech risks (Natural events triggering Technological disasters).     

Seismic vulnerability of gas and liquid buried pipelines

Lifelines play a crucial and essential role in human life and in economic development. The resilience of those systems under extreme events as earthquakes is a primary requirement, especially when large amount of toxic and flammable material are transported.In this work, the seismic vulnerability of buried gas and liquid pipelines has been analyzed, starting from a large number of damage data to pipelines collected from post-earthquake reconnaissance reports.Seismic fragility formulations and threshold values for the earthquake intensity with respect to the release of content from different types of pipelines have been derived. The main outcome of the work is therefore a novel seismic assessment tool which is able to cover the needs of industrial risk assessment procedures and land use planning requirements.     

化工园区地震Na-Tech事件快速风险评估方法

为有效评估地震灾害与化工园区工业事故的耦合风险,在分析地震灾害作用于化工园区致灾特征的基础上,理清化工园区的主要承灾体类型,辨识出地震破坏承灾体单元后引发的火灾、爆炸、中毒等工业事故的主要影响因素,采用层次分析法(AHP),提出综合考虑地震灾害与工业事故耦合作用的Na-Tech事件快速风险评估方法。该方法以化工园区企业为评估单位,根据评估结果划定企业Na-Tech事件风险等级,并将此方法应用于某化工园区企业的风险评估。结果表明:该方法可操作性强,计算所需数据量小,且能有效反映地震Na-Tech事件风险特点。