Abstract In this paper, a two-stage risk assessment approach for gas hydrate exploitation is presented. In the first stage, a probabilistic analysis method is used to evaluate the failure probability of submarine landslide due to hydrate exploitation. The excess pore pressure due to hydrate exploitation is evaluated using a proposed maximum excess pore pressure model, which can consider the equilibrium of pressure and temperature for hydrates during decomposition. An infinite slope stability analysis and Monte Carlo simulations are then used to evaluate the failure probability of the slope with consideration of the generated excess pore pressure. In the second stage, a Bayesian network model to estimate the mortality rate of platform workers is proposed based on the logical sequence of events. The proposed approach is easy to implement and provides an efficient approach for quantitative assessment of human risk. Application of the proposed approach to a potential hydrate exploitation area, the Shenhu area in the South China Sea, is presented. The probabilistic analyses reveal that the production temperature T1 and the slope angle β have significant influences on the failure probability. Analysis of the human risk suggests that the key factors affecting the mortality rate are the distance of the platform to landslide and the equipment time for the workers to equip with lifejackets.

中文翻译：

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天然气水合物开采诱发海底滑坡风险评估的两阶段概率方法

摘要 本文提出了天然气水合物开采的两阶段风险评估方法。第一阶段，采用概率分析方法评价水合物开采引起的海底滑坡破坏概率。使用建议的最大超孔压模型评估水合物开采引起的超孔压，该模型可以考虑水合物分解过程中的压力和温度平衡。然后使用无限边坡稳定性分析和蒙特卡罗模拟来评估边坡的破坏概率，同时考虑产生的超孔隙压力。在第二阶段，基于事件的逻辑顺序，提出贝叶斯网络模型来估计平台工人的死亡率。所提出的方法易于实施，并为人类风险的定量评估提供了一种有效的方法。介绍了所提出的方法在潜在的水合物开采区——南海神狐地区的应用。概率分析表明，生产温度 T1 和倾斜角 β 对失效概率有显着影响。对人员风险的分析表明，影响死亡率的关键因素是平台到滑坡的距离和工人配备救生衣的设备时间。概率分析表明，生产温度 T1 和倾斜角 β 对失效概率有显着影响。对人员风险的分析表明，影响死亡率的关键因素是平台到滑坡的距离和工人配备救生衣的设备时间。概率分析表明，生产温度 T1 和倾斜角 β 对失效概率有显着影响。对人员风险的分析表明，影响死亡率的关键因素是平台到滑坡的距离和工人配备救生衣的设备时间。