海洋平台的冰力谱与冰振响应分析

利用原型结构的直接冰力测量数据,建立了锥体结构的冰力谱模型.利用渤海辽东湾的JZ20-2MUQ平台对锥体冰力谱模型进行了验证.为了降低误差,在结构模型分析中,利用实测平台振动数据确定了平台的综合阻尼系数.利用谱分析方法计算了不同冰厚与冰速下的结构甲板振动响应,并与实测的结果进行了比较.结果表明,计算与实测的结构振动响应吻合的比较好,说明了建立的冰力谱模型具有实用性.

Ice force spectrum and analysis of ice-induced responses for offshore jacket platforms

Based on the data of field observation,the ice force spectrum of narrow conical structures is established.The dynamic responses of JZ20-2MUQ platform in Liaodong Bay are chosen to validate the ice force spectrum.In the dynamic analysis,the damping ratio of the structure is gained using the free damping curve of acceleration from field monitoring in order to reduce the computing error.The maximal acceleration responses of the deck under ice combinational condition of various ice thickness and ice velocity are computed by spectrum method,and the computing results are compared with that of field monitoring.The comparative results reveal that the computing responses accord well with that of field monitoring,which proves the practicability of ice force spectrum built.And the metods and results in this paper can be used in field forecasting of ice-induce vibrations and safety evaluation of ice-resistant platforms.