面向腐蚀环境的自升式海洋平台桩腿时变可靠性研究

以某公司300ft自升式海洋平台桩腿为研究对象，根据平台桩腿的工作环境的波高和波浪周期对其疲劳环境工况进行划分，采用Airy波理论和PM双参数谱计算平台桩腿不同工况下所受的波浪力谱，通过ANSYS有限元软件对平台进行三维建模，分析其在波浪力下的应力响应。建立桩腿在环境载荷下的可靠性模型，同时针对当前研究中的不足，考虑到腐蚀对于桩腿可靠性的影响，提出并建立在环境载荷与腐蚀耦合作用下的桩腿时变可靠性模型，根据应力响应分析结果，分析桩腿腐蚀最严重区域构件的时变可靠性变化规律，对比两种模型下的桩腿结构可靠性，确定腐蚀因素对桩腿时变可靠性的影响。根据可靠性分析结果，结合自升式海洋平台桩腿的工作环境和服役周期，为平台桩腿的维护与保养提供一定参考。

Time-dependent Reliability Research of Legs of Jack-up Platform for the Corrosive Environments

Taking the legs of 300ft jack-up platform as object, the fatigue environment conditions were divided according to the wave height and wave period in the working environment,wave force spectrum of legs was calculated with Airy wave theory and PM spectrum,a 3D model was established with ANSYS,stress response under different wave force spectrum was analyzed.The reliability modal was build,meanwhile,for the inadequates in the current research,against the leg corrosion phenomenon,the time-dependent reliability modal under the load and corrosion was established,according to the results of stress response analysis,variations of time-dependent reliability in the most serious area of corrosion was analyzed,the reliabilities were compared in both modals,the effects of corrosion factors to the time-dependent reliability were determined.According to the analysis results and working environment and service period,references for maintenance of jack-up platform during service were provided.