基于动态风险平衡的海洋平台事故连锁风险研究

针对海洋平台事故风险特点,提出动态风险平衡概念,以此建立事故动力模型,并将该模型运用到墨西哥湾"深水地平线"井喷事故。动态风险平衡表征事故动力与事故阻力之间的动态平衡状态,具有动态性和暂时稳定性。事故动力模型以海洋平台可能发生的重大事故为研究对象,从工艺、技术和管理等角度分析事故可能致因和事故发展可能影响因素。该模型首先分析对象的初始事故动力,建立事故连锁风险图,然后计算初始动力发生情况下,传递动力和传递阻力的概率分布,最后提出相应风险控制措施。实例分析表明,基于动态风险平衡建立的事故动力模型能有效分析海洋平台事故连锁风险。

On the risk chain of the offshore oil-drilling platform accidents based on the dynamic risk balance

The present paper is aimed at introducing a dynamic model for the offshore oil-drilling platform accidents proposed by the authors based on the two concepts,that is,the accident impetus and accident obstruction.As is well known,due to its own restricted conditions,offshore platforms,on the event of fire or explosion,are likely to suffer tragic casualties and material losses,letting alone the environmental contamination.Based on investigating and analyzing plenty of offshore platform accidents both at home and abroad,we have brought forward a new approach to dealing with such tragic accidents,that is,to finding the accident dynamic model characterized as dynamic nature and transient stability.As a matter of fact,a regular oil-drilling platform tends to present a dynamic equilibrium state between the accident impetus and the accident obstruction,while the accident dynamic state indicates a kind of energy that tends to lead to the happening of an accident whereas there exists some kind of transmitting impetus that passes on the energy that may obstruct or prevent the accident from occurring.In view of the dynamic risk balance,we have come up with the accident dynamic model consisting of four steps: first of all,the offshore platform likely to lead to grave accidents are chosen as an object of study,and next,the corresponding factors likely to cause the accidents are analyzed from the points of view of accident-incidence process,and,last of all,the countermeasures were taken in engineering,technology and management.What’s more,the risk statistical data and information concerning the accident chains are to be built up when the elementary accident impetus has been determined.And,by this moment,it would be necessary to work out the probability distribution of all transmitting impetus and obstruction factors in the circumstance that the elementary accident-incidence dynamic has been calculated.Furthermore,the analysis results should be made known to all the people concerned so that the risk prevention countermeasures are proposed in view of the former analysis and calculations.Thus,the accident dynamic model can thus be expected to be adopted to study the explosion accident of "Deepwater Horizon" platform in Gulf Mexico.In so doing,accidents can be avoided by taking countermeasures like using nitrogen foam cement,choosing a "long string" of deposited casing or temporary withdrawal of human resources from the endangered platforms.