【摘要】 对于半潜式钻井平台浮箱,裂纹的扩展不仅影响结构的水密性甚至可能对结构的安全产生巨大威胁,并直接决定平台的整体使用寿命。以南海某平台为研究对象,对浮箱板壳椭圆形表面裂纹前沿应力强度因子的分布规律,以及裂纹形状系数对裂纹前沿应力强度因子分布规律的影响等进行了研究。在此基础上,基于BS7910规范中‘合于使用’原则,对裂纹的临界状态进行了分析和评定,为海洋环境条件下半潜式钻井平台浮箱表面裂纹的极限尺寸研究提供了一种科学的方法。更多还原

【Abstract】 Cracks in the platform are inevitable due to fatigue damage of structure resulting from the action of wave loads.The evaluation of the influence of the existing cracks in the platform structures has been an academic difficulty for decades.For semi-submersible platform pontoons,the propagation of the cracks not only influences the water-tightness of the pontoons,but also jeopardizes the platform.It also determines the service life of the overall structure directly.A semi-submersible platform servicing in South China Sea is used for the analysis in this paper.The surface crack of the pontoon shell plate is simulated by using the ABAQUS program.The distribution of the stress intensity factor of the elliptical surface crack front and the influence of the shape factor on it are investigated.Based on "Fit For Service" and BS 7910,the engineering critical assessment of the cracks in the pontoons is performed,and the allowable maximum dimension of the cracks can be determined.This paper provides a method of safety evaluation on the cracked SS platforms.更多还原