超深水钻井船总强度评估的应力设计波法研究

Research on design wave approach based on stresses for an ultra-deepwater drillship

针对超深水钻井船总强度评估的等效设计波方法进行了探索研究。鉴于超深水新型钻井船的月池开口对船体强度具有重要影响,特别针对月池角隅位置探索了以应力为目标的设计波研究方法,针对目标单元进行屈服校核。通过比较分析基于传统主控载荷设计波和应力设计波的船体结构应力结果,探索应力设计波方法在超深水钻井船上的应用。结果表明,应力设计波法对关键位置的应力极值搜索更为全面,得到的结构关键位置的屈服应力总体上大于传统主控载荷设计波法,能够更全面地涵盖目标位置可能出现的最大应力。基于应力设计波法对具有特殊结构的新型钻井船总强度进行评估,可以弥补传统主控载荷设计波方法的不足,更好的保证船体结构安全。

Design wave approach based on structure stresses is studied for the overall strength evaluation of an ultradeepwater drillship.In the view of the important influence from the large opening of moonpool,the ship strength and stress of moonpool corner are evaluated using the design wave approach based on stress,then compared with results from using the traditional design wave approach based on main loads.The comparison shows that:the design wave approach based on stress searches the maximum stresses of key structure more comprehensively.The obtained yield stresses are generally larger than the corresponding results from using traditional design wave method,and the method can cover the possible max stress more widely.Using the design wave method based on the stress to evaluate the overall strength of new-type drillship with special structures such as large moonpool,can cover the weakness of traditional design wave method,and provide better insurance for the safety of ship structure.