2009 Fiscal Year Final Research Report
Impact Load by an Ice Floe against a Structure
Project/Area Number |
19760349
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Research Category |
Grant-in-Aid for Young Scientists (B)
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Allocation Type | Single-year Grants |
Research Field |
水工水理学
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Research Institution | Public Works Research Institute |
Principal Investigator |
KIOKA Shinji Public Works Research Institute, 寒地土木研究所寒地水圏研究グループ寒冷沿岸域チーム, 主任研究員 (20414154)
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Project Period (FY) |
2006 – 2009
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Keywords | 海氷 / 衝撃 / 衝突 / 個別要素法 / 津波 / 破壊 |
Research Abstract |
We performed medium-scale experiments regarding the impact applied by ice floes against a structure using free-falling ice floes under various conditions. The impact load increased linearly with decreasing ice temperature ; accordingly, it was presumed that the effect of ice temperature on the impact load was larger than that on compressive strength. The impact load was also more strongly influenced by ice temperature than by kinetic energy under the test conditions of this study. When ice causeed brittle failure/splitting, and fragments moved freely after impact with a structure (especially when the ice floe is large compared to the structure), the impact load or the impulse was small compared to cases without failure, and became a constant value regardless of the level of the kinetic energy or the momentum. We also made experiments regarding timbers and steels along with sea ice, considering tsunami-related debris such as timber, containers and vessels. In case of the timbers and the steels without brittle failure, their impact loads were generally one order of magnitude larger than those of sea ice. We also developed a numerical method using DEM to simulate the impact on a structure and its failure, and we obtained a practical tool for estimating an impact load of sea ice.
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