基于现场监测的海洋平台冰振控制效果评价

渤海辽东湾的ＪＺ２０－２ＮＷ 平台采用甲板阻尼隔振技术降低平台的冰激振动问题。根据海洋平台冰激振动的特点，设计现场监测系统，检验阻尼隔振系统的减振效果。对平台隔振的上下两层甲板的加速度和相对位移响应进行监测，并对实测数据进行对比分析。监测结果表明，上层甲板的振动强度相比下层甲板有所减弱，阻尼隔振装置起到控制上层甲板振动的效果。但是上下甲板的振动频率和相位无差别，说明减振装置未产生最理想的减振效果。同时对有无阻尼隔振装置结构的阻尼比进行提取，表明相对位移越大，上下甲板的阻尼比越大。减振后上下甲板的阻尼比都有所增加，结构振动耗能增加。应用实践表明，阻尼隔振技术是一种有效的海洋平台冰激振动减振措施，但仍有许多地方需要完善。

Ice-induced vibration control effectiveness evaluation for an offshore platform based on a field monitoring

For JZ20-2NW platform,the damping isolation technology was used to reduce ice-induced vibration problems.In order to test its vibration-suppressing effect,accelerations and relative displacements of the two decks were measured and analyzed.The results showed that the vibration intensity of the upper deck was weaker than that of the lower deck;the damping isolation device is effective to reduce the vibration of the upper deck.The structural damping ratios with and without the damping isolation device were calculated.It indicated that the structural damping ratio increases and the energy consumption grows after installing the damping isolation device.The attempt to a real platform showed that the damping isolation system is an effective method for ice-induced vibration control of an offshore platform,but there are a lot of places can be improved.