化工园区多灾种耦合关系模型及断链减灾模式

化工园区危险源众多,在各类自然灾害及工业事故影响下极易发生级联效应,扩大事故后果,灾害与事故之间的耦合关系及断链减灾工作逐渐受到广泛关注。本文通过统计分析自然灾害诱发的化工事故（Na-Tech）,分析单一自然灾害与工业事故之间及化工园区多灾种之间耦合关系的形成机理,明确灾害与事故耦合关系特点;应用复杂网络理论,探讨灾害事件间的直接及间接作用关系,建立化工园区多灾种耦合关系数学模型,并提出基于网络节点重要度的断链减灾模式;以某化工园区为例,应用统计数据及数学模型,通过对比不同网络节点对系统扰动值的影响程度,对实例园区开展断链减灾分析。为园区灾害及事故预防、断链减灾、应急救援等工作的开展提供参考依据。     

化工园区Na-Tech事件定量风险评价与防控体系评述

Na-Tech（natural-technological）事件是典型的HILP（high-impact low-probability）事件，近年来时有发生，尤其是在危险源高度集中的化工园区。Na-Tech事件演化过程和机理的高度复杂性，使其成为风险评价领域的研究难点。对Na-Tech事件统计文献进行分析，理清最频发的自然灾害类别、最脆弱的设备类型及其致损模式等特性和规律，进一步探究Na-Tech事件演绎过程，包括自然灾害和技术灾害。对当前文献中Na-Tech事件定量风险评价方法进行深入剖析，指出自然灾害与技术灾害的设备致损概率计算是其核心问题。从土地使用规划，设备完整性、鲁棒性与本质安全工艺，安全防护设施，安全教育、管理与合作，事故应急响应，灾后恢复与重建等六方面探讨了Na-Tech事件防控体系。指出自然灾害条件下的设备易损性和多致灾因子耦合作用是Na-Tech事件研究的突破方向，也是进行定量风险评价的关键环节。     

Risk assessment and early warning systems for industrial facilities in seismic zones

Industrial equipments and systems can suffer structural damage when hit by earthquakes, so that accidental scenarios as fire, explosion and dispersion of toxic substances can take place. As a result, overall damage to people, environment and properties increases. The present paper deals with seismic risk analysis of industrial facilities where atmospheric storage tanks (anchored or unanchored to ground), horizontal pressurised tanks, reactors and pumps are installed. Simplified procedures and methodologies based on historical database and literature data on natural-technological (Na-Tech) accidents for seismic risk assessment are discussed.Equipment-specific fragility curves have been thus derived depending on a single earthquake measure, peak ground acceleration (PGA). Fragility parameters have been then transformed to linear probit coefficients in order to obtain reliable threshold values for earthquake intensity measure, both for structural damage and loss of containment. These threshold values are of great interest when development of active and passive mitigation actions and systems, safety management, and the implementation of early warning system are concerned.The approach is general and can be implemented in any available code or procedure for risk assessment. Some results of seismic analysis of atmospheric storage tanks are also presented for validation.     

Definition of a short-cut methodology for assessing earthquake-related Na-Tech risk

Na-Tech (Natural and Technological) refers to industrial accidents triggered by natural events such as storms, earthquakes, flooding, and lightning. Herein, a qualitative methodology for the initial assessment of earthquake Na-Tech risk has been developed as a screening tool to identify which situations require a much more expensive Quantitative Risk Analysis (QRA). The proposed methodology, through suitable Key Hazard Indicators (KHIs), identifies the Na-Tech risk level associated with a given situation (i.e., a process plant located in a given territory), using the Analytical Hierarchy Process as a multi-criteria decision tool for the evaluation of such KHIs. The developed methodology was validated by comparing its computational results with QRA results that involved Na-Tech events previously presented in literature.