海底管道基于风险和可靠性理论的合于使用评价

Fitness for Service Assessment for Submarine Pipelines Based on Risk and Reliability Theory

在以往的海底管道合于使用(FFS)评价方法中,管道目标可靠性的识别和应用仅基于定性判断和经验,为进一步量化预估风险,需要建立一种基于风险和可靠性理论的FFS评价方法。该方法首先进行定量风险评价(QRA),确定不同管道分段的目标可靠性,并将结构可靠性分析(SRA)方法应用到计算最大安全运行压力的过程中,最终完成合于使用评价的流程,形成了一整套从定量风险分析结果到为合于使用评价提供剩余承压能力的定量计算方案。通过案例对剩余承压能力进行计算,对比了基于风险和可靠性理论的剩余承压能力计算结果及单独使用规范的计算结果,结果显示基于风险和可靠性理论的剩余承压能力计算结果是可靠的;调整定量风险分析策略时,应用该方法可以得到分档型变化。因此,基于风险和可靠性理论的合于使用评价是对规范的科学补充和应用。

In the traditional fitness-for-services(FFS) assessment method, the identification and application of pipeline target reliability is merely based on qualitative judgments and experience.In order to further conduct the quantitative evaluation of risk,a FFS assessment method based on risk and reliability theory should be established.The method firstly conducts the quantitative risk assessment(QRA)and determines the target reliabilities for different pipeline segments.And then,the structure reliability analysis(SRA) method is used to calculate the maximum safe operating pressure. Finally the flow of FFS is completed and a whole set of quantitative calculation method from getting quantitative risk analysis results to providing residual pressure bearing capacity for FFS assessment is developed. The residual pressure bearing capacity is calculated through the case, and the calculation result of residual pressure bearing capacity based on risk and reliability theory and that only based on standards are compared.The comparison result shows that the result of the method is reliable,and when the quantitative risk analysis strategy is adjusted,classified change can be got.Therefore,the FFS assessment based on risk and reliability theory is scientific supplement and application for standards.