海冰强度对应变速率敏感性及其演化模式  

Sea ice strength sensitivity to strain rate and its evolution mode

作　　者：李洪升[1] 杜小振[1] 岳前进[1] 

机构地区：[1]大连理工大学工业装备结构分析国家重点实验室,辽宁大连116024

出　　处：《大连理工大学学报》2003年第5期686-690,共5页Journal of Dalian University of Technology

基　　金：国家自然科学基金资助项目(59739170).

摘　　要：海冰对应变速率变化较敏感,在不同应变速率范围内可表现出不同的力学行为和强度特性.如辽东湾海冰在低应变速率下(ε.<1.0×10-3s-1),表现为连续体特征,其变形行为符合流动定律;在高应变速率下(ε.>3.0×10-3s-1),表现为脆性体特征,强度特性可用断裂力学理论描述;在韧-脆转变的范围内(1.0×10-3s-1<ε.<3.0×10-3s-1),海冰强度达到最大值.因此在不同应变速率段,海冰强度具有不同的本构模型.用海冰演化模式对辽东湾海冰(T=268K,d=7.0mm)进行了数值计算,结果与实验值十分吻合,说明该演化模式是有效的.Because of its strength sensitivity to strain rate, sea ice displays different mechanism behavior and strength features in different range of strain rate. The sea ice at the Liaodong Bay of Bohai shows continuous properties and its deformation behavior conforms flow rule in the condition of low strain rate (ε·<1.0×10-3 s-1); it shows fracture properties and the strength features can be described by fracture mechanics theory in the condition of high strain rate (ε·>3.0×10-3 s-1), in the range of the ductile tobrittle transition of sea ice material (1.0×10-3 s-1<ε·<3.0×10-3 s-1), the ice strength reaches to the maximal value. In different strain rate section, sea ice has a different constitutive model, the evolution mode of sea ice should be described in divided sections. So the sea ice strength related to its strain rate about the Liaodong Bay sea ice (T=268 K,=7.0 mm) is calculated. The result indicates that this evolution mode is effective because the calculation result is consistent with the experimental value very well.

关 键 词：冰力学 海冰强度 应变速率 敏感性 演化模式 韧-脆转变 断裂力学 本构模型 

分 类 号：P731.15[天文地球—海洋科学]