极端波浪载荷下导管架平台抗倒塌性能评估

提出载荷序列增量分析(LSIA)方法,对极端波浪载荷下导管架平台结构极限状态进行分析。LSIA能够考虑不同波高及可能的甲板上浪载荷对平台侧向载荷分布的影响,"追踪"平台在不同载荷重现期作用下的真实响应,从而克服当前Pushover的缺点。基于LSIA等效承载能力曲线,提出倒塌重现期NCP,使得平台抗倒塌能力评估指标具体化。以K型和X型两种不同结构形式的导管架平台为例,采用LSIA方法对其进行抗倒塌性能评估,并与Pushover进行分析对比。结果表明,LSIA具有更高的评估精度,能够确定平台结构真实的倒塌状态与失效模式。

Anti-collapse performance assessment of jacket offshore platforms in extreme storm waves

A novel approach called load sequence incremental analysis (LSIA) was established to estimate the ultimate limit states and accurate behaviors of jacket platforms against extreme environmental loading. This approach could take into account the effects of variation in wave height and wave-in-deck loading, and track the actual behavior of platform under different load return periods. Thereby, the shortages of current Pushover analysis (CPA) were overcome. Based on the equivalent bearing capacity curve obtained by LSIA, a parameter called collapse return period (NCP) was introduced, which made the evaluation indicator of platform performance more specifical. On this basis, LSIA was used for the anti-collapse performance assessment of K platform and X platform. The results show that LSIA can achieve better assessment precision than CPA, and be able to determine the real collapse state and failure mode of platforms.