| 摘要: |
| 基于不同制冰条件和厚度的细粒酒精模型冰层原位悬臂梁弯曲强度试验，给出细粒酒精模型冰弯曲强度；分析了考虑和不考虑浮力效应对弯曲强度的差异；利用向上和向下弯曲强度结果给出该模型冰各向同性的证据；得到该冰弯曲强度与其密度、冰内未冻液含量和制冰过程可控制因子（冰地室内温度、升降温时间、冰厚）的关系，并作为定量控制模型冰质量的基础。 |
| 关键词: 细粒酒精模型冰 弯曲强度 试验研究 |
| DOI： |
| 分类号: |
| 基金项目:国家海洋局青年海洋科学基金资助项目，96－505号;国家教委重点科技项目，97－87号 |
|
| EXPERIMENTAL STUDY ON THE FLEXURAL STRENGTH OF FINE GRAIN ETHANOL MODEL ICE |
|
LI Zhi-jun1,2, RISKA Kaj3
|
|
1.National Marine Environmental Monitoring Center;2.Dalian University of Technology, 116024;3.Helsinki University of Technology, FIN 02150, Espoo, Finland
|
| Abstract: |
| The fine grain ethanol model ice, used in the Arctic Offshore Research Centre (AORC), Ship Laboratory, Helsinki University of Technology, is of international standard for modeling interactions between model ice and structures (ships). One of the important laboratory simulation results is concerned with the model ice properties. For the interactions with inclined structures and ships, such as cone man-made islands, lighter towers, wave dams and ice-breakers, model ice flexural strength is one of the dominant factors. A series of experimental studies have revealed the physical and mechanical properties of fine grain ethanol model ice and their relations to the known ice-making conditions (i.e. air temperature in ice basin, time periods of decreasing and increasing air temperature, and model ice thickness) and yielded a new index, θ*t/h2 based on the energy balance. This paper presents the experimental study theory, method and results on the fine grain ethanol model ice flexural strength. The effects of buoyancy, loading rates and loading directions on the model ice cantilever beam flexural strength are discussed. The authors' findings that flexural strengths loading downwards and upwards are nearly the same (the homogeneity of the fine grain model ice) are confirmed. The processes affecting the strength with loading rates are similar to those for the natural sea ice in the Bohai Sea. The effect of buoyancy on the strength is smaller than the error which comes from tested data. The flexural strength depends on its physical properties, and decreases with ice density, the increasing of unfrozen solution in the ice, and the increase in the new evaluation index. From energy balance, the larger the index is, the more the unfrozen solution in the ice is, and the higher the ice density. |
| Key words: Fine grain ethanol model ice, Flexural strength, Experimental study |
