【作者】 刘爱华；

【导师】 吴超；

【作者基本信息】 中南大学 ， 安全科学与工程， 2013， 博士

【摘要】 摘要：随着城市化进程的加快,城市灾害的链式效应越来越明显,因为灾害链式效应所造成的损失也越来越巨大。因此以灾害链为核心对城市灾害进行风险评估,才能全面、系统地把握城市灾害的隐患程度,为构建城市综合防灾减灾体系、以及城市灾害风险管理提供可靠的理论依据。本文针对城市灾害链和风险评估当中的一些关键问题作了以下几个方面的研究：(1)对城市灾害链的形成机理进行了分析,结果表明在致灾因子作用下各承灾体之间复杂的相互作用关系是城市灾害链产生的直接原因。对四种典型城市灾害的链式效应进行了分析,指出城市灾害链具有复杂的网络结构特征。城市灾害链的能量效应分析表明致灾体所释放出的激发能,与各承灾体能量的耦合作用是产生城市灾害链的根本原因。(2)对城市灾害链的演化规律进行了分析,城市灾害链在演变过程中具有阶段性孕育特征,在时间效应上具有持续性影响和瞬时性影响两种不同的演化行为。以灾害链的演化规律为基础,建立了基于复杂网络的灾害链数学模型,描述了各灾害节点的灾害损失速率和灾害损失度,并提出了基于网络节点脆弱性和连接边脆弱性的断链减灾模式。(3)以城市灾害链系统动力机制描述为基础,先进行了灾害场景的设定,并考虑时滞性的影响,建立了城市灾害链和城市灾害管理的系统动力学模型。并利用Vensim对城市灾害链系统的演化过程进行了仿真分析,得到了主要承灾体易损性与灾害损失速率之间的影响关系,指出降低城市生命线的易损性是降低在城市灾害中人员伤亡率最有效的方法。城市灾害管理系统动力学模型表明了灾害与经济之间相互影响、相辅相成的关系,指出强调灾害管理系统的溢出效应能提高减灾的有效性。(4)分别建立了人口、建筑物和生命线系统等城市主要承灾体的灾损敏感性评估模型。用人体的忍耐力和应急自救能力表征了人在渐发性灾害和突发生灾害时的灾损敏感性,用建筑物的结构指数和使用时间指数表征了建筑物的灾损敏感性指数。利用均衡熵和脆性熵理论分别对单功能网络的脆弱性和各生命线子系统脆性关联程度进行了表征,建立了生命线系统的灾损敏感性评估模型。(5)从基础应灾能力和专项应灾能力两个方面,建立了多层次的城市应灾能力评价指标体系。在对指标体系进行可量化处理的基础上,采用改进层次分析法确定了各指标的权重系数。考虑到城市应灾能力评价指标的模糊性和层次性,建立了基于模糊模式识别的模糊综合评判模型,通过构造出各指标的最优隶属度,使得城市应灾能力的评价更加科学和准确。(6)在分析多灾种风险评估和供应链风险评估方法的基础上,运用贝叶斯公式得到各节点灾害损失等级的联合概率分布,构建了城市自然灾害链的风险评估模型；以多米诺效应为核心建立了城市技术灾害链的风险评估模型。并通过应用实例表明所建立的模型与实际情况具有较高的吻合性,说明了模型的实用性。更多还原

【Abstract】 Abstract:As the urbanization process is accelerating, the chain effect of urban disaster becomes more and more obvious, and the loss caused by the disaster chain effect is bigger and bigger. Therefore the urban disaster risk assessment must put the disaster chain as a core, it is possible to comprehensively and systematically grasp the hazard degree of urban disasters. Then the assessment can provide reliable theoretical basis for building regional integrated prevention and mitigation disaster system, and urban disaster risk management. The thesis focuses on some key technology of the city disaster chain and risk assessment, and the main effects are as follows:(1) The formation mechanism of urban disaster chain is analyzed, and the result shows that the complex interaction relation of the disaster carrying bodies is the immediate cause of disaster chain effect. The analysis for chain effect of four kinds of typical urban disaster shows that the urban disaster chain has complex network structure characteristics. The energy effect of the city disaster chain indicates that the coupling effect of the excitation energy releasing from disaster-inducing factors and the energy of the disaster carrying bodies is the root cause of the disaster chain.(2) The evolution regulation of urban disaster chain is analyzed. The result shows the urban disaster chain has periodic inoculation characteristics, and there are continuous influence behavior and instantaneity influence behavior, two different behaviors in time effect. Based on the evolution rule of disaster chain, the mathematical model of disaster chain is established to describe the disaster loss rate and the degree of disaster loss of various disaster nodes. And the model to cut off disaster chains and mitigate disaster is put forward based on the vulnerability of disaster nodes and the connection sides.(3) On the basis of description of the dynamic mechanism of urban disaster chain system, the disaster scene is set at first, considering the influence of time lag, then the system dynamics model of urban disaster chain and urban disaster management is established. With Vensim, the simulation analysis software, the evolution process of urban disaster chain system is analyzed, the effect relation has been gotten between the vulnerability of part of disaster carrying bodies and disaster loss rate, and it is pointed out that the most effective method of reducing personnel casualties in the urban disaster is to reduce the vulnerability of urban lifeline. The system dynamics model of urban disaster management shows that there is the interference and supplement relationship between disasters and economic, and to emphasis on spillover effects of the disaster management system can improve the effectiveness of reduction disaster system.(4) The disaster loss sensitivity evaluation models of the main disaster carrying bodies such as population, urban buildings and lifeline have been respectively established. The body’s endurance and emergency self-help ability characterization are respectively used to characterize the disaster loss sensitivity of gradual disasters and suddenness disasters. The index of the building structure and the index of use of time are used to characterize the disaster loss sensitivity of building. Using the theory of equilibrium entropy and brittle entropy the vulnerability of single function network and the subsystem brittleness association degree are characterized, lifeline system damage sensitivity evaluation model is established, then the disaster loss sensitivity evaluation models of the lifeline is established.(5) From two aspects of fundamental disaster emergency ability and special disaster emergency ability, the multi-level index system of urban disaster emergency ability evaluation is established. On the basis of quantifiable change for the index system, the weight coefficient of each index is determined with the improved hierarchy analytic method. Considering fuzzy and hierarchy of the evaluation index system of the urban disaster emergency ability, the fuzzy comprehensive evaluation based on fuzzy pattern recognition is established. The optimal membership degree of each index is constructed so that the evaluation of urban disaster emergency ability is more scientific and accurate.(6) Based on the analysis of multi-risk assessment methods and risk assessment methods of supply chain, then the joint probability distribution of disaster loss grade of every node is obtained using Bayesian formula. And the risk assessment model of urban disaster chain is constructed. Considering the differences between disaster chains caused by technology disasters and natural disaster chains, the risk assessment model of urban technology disaster chains is set up taking the domino effect as the core. And the application examples show that the model established has higher consistency with actual situation, this also explains the model is practicability.更多还原