Submarine Pipeline Quantitative Risk Assessment (QRA) And Its Application In Integrity Management

China has rich offshore oil resources. During the development of China's offshore oil and gas, the operational status of subsea pipeline is directly related to the safety of offshore oil and gas fields. Therefore, the analysis of pipeline risk, and based on which the establishment of a rational submarine pipeline integrity management system to ensure the normal operation of pipelines has a very important significance to the offshore petroleum development of China.Chapter I of this paper exposed the research progress of the technique of domestic and international risk-based analysis and pipeline integrity management, pointed out its direction of the trend from semi-quantitative and semi-quanlitatve analysis to quantitative analysis, but also the focus of risk analysis and management is pipeline failure probability calculation and control.Chapter II used the fault tree analysis method, established a relatively complete subsea pipeline failure fault tree; found the fault tree minimal cut sets; given out a solving method of pipeline failure probability calculation based on basic event probability and the minimum-cut-set probability; and simplified the calculating of the importance coefficient of basic event probability with its significance on pipeline risk analysis and integrity management pointed out.Chapter III studied the famous British PARLOC submarine pipeline database to calculate basic event probabilities of fault tree, and analyzed the advantages and disadvantages of the method.Chapter IV, based on the ultimate strength formula in ASME G31G new criterion, corrected the corrosion area calculation method; established a structure reliability model for subsea pipeline corrosion failure probability calculation; and simplified the ultimate limit state equation by normalizing random variables;researched and given out the distribution types of the normalized random variables and suggested their characteristic value; and at last, the parameters discussing was performed to demonstrate the model reliability. Chapter V, by referring to Specification DNV-RP-F107 the method for calculating object impact fallen from crane caused pipeline failure probability, established a probability calculation model for pipeline ship anchoring impact. And then, discussed the conditional probability of pipeline failure during an accident of anchor impact, and summarized the pipeline conditional failure probability of the impact from different anchor sizes. Finally, according to statistics of shipping in China, the parameters discussing was performed at the condition of the impact of typical weight anchor to demonstrate the model reliability.This study of this paper laid the foundation for China's future theoretical research on subsea pipeline risk analysis based integrity management method and also its engineering appliance.