含贯穿性损伤海洋平台结构强度分析

采用有限元方法,通过局部实体建模,提出一种海洋平台整体结构有限元分析方法,用实体模型模拟海洋平台构件连接处的贯穿性开裂损伤。建立多损伤模型,分析局部损伤对海洋平台结构整体强度的影响。以渤海的某一现役导管架平台为研究对象,根据设计规范,分析在环境极值载荷下平台的应力场。研究表明,当开裂损伤圆周弧长大于110°时,平台最大应力发生在损伤处,开裂损伤边缘应力值超过材料的屈服极限,使导管架撑杆产生塑性变形,最终会导致管件断裂。研究方法为现役平台的分析与评估提供了更为精确和符合实际的手段,为海洋平台的检测、维修决策和结构承载潜力挖掘提供了科学依据。

An analysis of the structural strength of offshore platform with cracking beam

Adopting the finite element method and depending on local solid modeling,a kind of finite element analysis method of the whole structure of the offshore platform was formulated.The solid model was used to simulate the penetrating fracturing damage at the joint of the component parts of the offshore platform.The multi-damage model was established and the effect of local damage on the strength of the whole structure of the platform was analyzed.With a current jacket platform located in the Bohai Sea as the object of study,the stress field of the platform under the environmental extreme load was analyzed according to the design specifications.The research shows that,when the length of circumference of the fracturing damage was greater than 110°,the maximum stress of the platform took place at the damaged portion and the stress value of the damage edge went beyond the yield limit of the material so as to cause the plastic deformation of the jacket and finally lead to the breaking of pipes.The research method provides the more precise and more practical means for the analysis and evaluation of the current platform,and provides the scientific basis for the detection,maintenance decision-making and potential bearing capacity mining of the offshore platform.