船-冰碰撞载荷时间历程的模型试验研究

A model test study on the time history of ship-ice impact loads

船-冰碰撞载荷是极地船舶船体外板结构强度的设计载荷,但目前的极地船级规范中尚未涉及船-冰碰撞载荷的时变特征。以我国新一代极地科考船为原型开展室内冰水池物理模型试验,对船首与浮冰的碰撞过程进行模拟;试验测试以主拖车拖曳船模撞击浮冰的方式进行,碰撞过程中船体所受冰载荷由布置在船首表面的触觉传感器测得。试验发现:船-冰碰撞过程中的整体冰载荷沿船体外板的作用呈现出近抛物线的轨迹,同时,载荷经历了先上升、后下降的完整过程,最大载荷作用时刻出现在冰体最大下压弯曲变形时刻;此外,最大载荷出现的水平位置集中在1/4船宽附近,相应局部碰撞载荷的时程曲线特征以‘单峰’型形态为主。

The ship-ice impact load is the governing load in the design of bow structures for ice class ships.A series of model tests were conducted in the ice tank of Tianjin University to investigate the time history of the ice impact loads.The tests were performed by towing the model ship striking large ice floes,and the ice impact loads on the model ship hull were measured by tactile sensors.According to the test results,the ice loading track on the ship hull during ship-ice impact was found to be parabolic,and the ice load increased firstly,then decreased.The maximum ice loading moment was found to be the moment when the ice deflected most.Furthermore,the maximum ice loading location was found near the 1/4 beam,and the time history of the corresponding local ice impact load was mainly characterized by a single-peak shape.