辽东湾东岸海冰物理力学性质的基本特性

The physical and mechanic properties of sea ice in the eastern coast of Liaodong Bay

海冰物理力学性质研究对涉海经济活动的防冰抗冰有着重要意义。本文基于辽东湾东岸将军石港附近海域的海冰现场观测与力学性能测试,采用控制变量与统计的研究方法,分析了该海域海冰物理性质与力学性质。研究发现,冰面下10 cm位置时的海冰平均温度为-6.98℃、平均盐度为11.8、海冰密度平均值为0.892 g/cm^(3);冰层24 cm以上表现为粒状冰特征,24 cm以下呈现柱状冰特征。力学性质研究表明,海冰温度对粒状冰过渡区的压缩强度较为敏感,粒状冰压缩强度对加载方向不敏感,粒状冰压缩强度明显高于柱状冰;对于弯曲强度,随着应力速率的增大,弯曲强度为先增大、后减小的趋势;随着海冰温度的降低,弯曲强度峰值对应的加载速率逐渐减小;粒状冰垂直加载的弯曲强度明显高于水平加载。在此基础上,给出卤水体积分数与海冰力学强度的关系图,得出海冰力学强度随卤水体积分数的演变规律。本文工作可为辽东湾东岸海域海洋工程结构的防冰抗冰提供重要支撑。

The study of the physical and mechanic properties of sea ice is great significance for the prevention of sea ice disasters.Based on the sea ice observation and mechanics performance test in the Jiangjunshi on the east coast of Liaodong Bay in the winter of 2010-2011,the physical and mechanic characteristics of sea ice in this area are analyzed by means of control variables and statistics.The physical properties show that the average sea ice temperature at 08:00 at 10 cm is-6.98℃,the average salinity is 11.8,the average sea ice density is 0.892 g/cm^(3);Ice thickness of more than 24 cm is characterized by granular ice,and below 24 cm is characterized by column ice.The study of the mechanic properties shows that temperature is sensitive to the transition area of granular ice compressive strength,temperature is not sensitive to the compressive strength of column ice,the compression strength of granular ice is not sensitive to the loading direction,and the compression strength of granular ice is significantly higher than that of column ice;For bending strength,with the increase of stress rate,bending strength shows the tendency of increasing first and decreasing later;with the decrease of sea ice temperature,the loading rate corresponding to the peak of bending strength decreases gradually;and the vertical loading of granular ice bending strength is obviously higher than horizontal loading.Based on the above conclusions,the relationship between vb and sea ice mechanics strength fitting is obtained.The work carried out in this paper is the basis of the anti-ice disaster work in the eastern coast of the Liaodong Bay.