服役后期海洋平台剩余寿命可靠度预测方法

Study on Post-service Jacket Platform Residual Life Reliability Prediction Method

为保证服役后期平台在延寿服役期内的安全性,需要对其结构整体剩余寿命可靠度进行预测.因此,重点研究了在随机波浪载荷作用下平台部分构件动力失效和疲劳失效时,平台整体时变可靠度预测方法.采用Miner线性累积损伤理论和首次超越失效准则,计算平台构件的疲劳寿命可靠度和动力可靠度,搜索并删除失效概率较大的构件,运用波浪增量动力分析法找出平台结构所能承受的极限波浪载荷,再结合服役海域波浪统计资料,计算平台结构系统整体时变可靠度以预测其剩余寿命.算例表明了该方法的实用性和简便性.

To ensure the post-service platform security in the late service period, it is necessary to predict platform structure residual life reliability. This paper focuses on platform global time-varying reliability re- sulting from component dynamic failure and fatigue failure under random wave loads. Firstly component fatigue reliability and dynamic reliability were calculated according to Miner linear cumulative damage theo- ry and first crossing failure criteria, components with larger failure probability were searched and deleted. Then the wave incremental dynamic analysis was used to find the limiting wave height which the platform could bear. Finally combining with the wave statistics, platform global structure time-varying reliability was calculated to predict the residual life. The example shows the practicality and simplicity of the pro- posed method.