海冰对圆台结构的作用力及结构相互遮蔽关系  

Ice Forces on Conical Structures and Shielding Relation between Conical Structures

作　　者：李志军[1] 董吉武[1] 芦志强[2] 杨晓彤[2] 王昕[1] 王国玉[1] 

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024 [2]中交水运规划设计院有限公司,北京100007

出　　处：《冰川冻土》2008年第3期514-519,共6页Journal of Glaciology and Geocryology

基　　金：中国石油天然气集团公司青年创新基金项目(05E7005);长江学者和创新团队发展计划项目(IRT0420)资助

摘　　要：利用非冻结模型冰进行海冰对圆台结构上的水平和垂直冰作用力物理模拟试验研究,给出作用在单圆台结构上水平和垂直冰力上限值同抗弯强度的包络线关系.对于同类型的圆台,能够依照一定模型比尺下的模型冰抗弯强度确定作用在圆台上的冰作用力试验值,然后按照相似比尺复原到原型冰力.当相邻两个圆台结构物距离比较近时,圆台结构物之间会发生相互遮蔽.通过系列不同相邻结构间距和夹角的物理模拟试验,结合几何投影关系和圆台结构物前冰层的破碎特点及前人已有简单结构的试验理论关系形式,利用新的物理模拟数据拟合出两个圆台结构之间冰力遮蔽系数同几何遮蔽系数的试验关系.The synthetic model ice, DUT-1 model ice, was used to conduct a series of physical simulation tests. The ice horizontal and vertical forces on conical structures, which are used in Bohai LNG port to resistant the loads from drift sea ice, were tested. The tested ice sheet thickness was 8 -10 mm and their flexure strength was between 13.8 and 73.2 kPa, their elastic modulus were 17.1-420.4 MPa. Most cases of the ratio of elastic modulus to flexure strength are over 2000. The special water flume, which was built for the ice physical simulation tests, is 20 m in length, 2 m in width and 1.2 m in depth. The simulation scale is 50 with respect to Bohai ice thickness at return period of 50 years. Before the series of tests performed, a series of checkout tests for the ice force measurement system were done. In this way, the ice force measurement system is confirmed because the ice forces on the conical structure can not be verified by theories. A steel pile with 32 mm in diameter was selected. 16 measured ice forces on the pile are compared with the computed forces based on Afanasev＇s ice force formula on vertical piles. The comparison results are good enough and the conical structure models are instead of the pile structure model. Total 33 model tests of single conical structure with model ice were performed, and the results are used to set up the relations of ice vertical and horizontal forces and ice flexure strength. From these scattered points between ice forces and flexure strength, the upper bounds of the ice forces and flexure strength are fitted as a logarithm curve. From model scale, the model ice flexure strength can be found. With the flexure strength, the ice forces on the conical structure can be determined. The full scale ice forces on full scale structure are 3 power of model scale multiply the model ice forces. While over two conical structures are built in the engineering area, the shielding effect between two conical structures is obvious. In this case, the structure shielding effect shou

关 键 词：海冰 作用力 圆台结构物 物理模拟 

分 类 号：P731.15[天文地球—海洋科学]