Development Of Ice Impact Test Equipment And In-situ Experimental Study

The mechanical properties of ice are important parameters that need to be considered in the design and safe navigation assessment of icebreakers.The speed at which the icebreaker interacts with ice during the ice-breaking sailing process has exceeded the scope of the traditional ice compression strength test.In order to explore the ice damage mechanism under impact,based on the previous tests,the ice impact test machine was designed and developed by itself.The drop-weight impact testing machine and the in-situ pendulum impact testing machine use the ice impact testing machine to conduct equipment verification tests and impact tests indoors and outdoors.After the two are used,the impact test is performed on-site,and in the winter of2019-2020 in Liaodong Bay In the coastal lagoon,using a self-developed ice impact testing machine,the impact tests were carried out on ice samples of two sizes under the conditions of five impact speeds,three impact head shapes,and nine impact head sizes.In the winter of 2020-2021,impact tests were carried out on the ice surface using a falling weight impact testing machine and an in-situ pendulum impact testing machine at the same location using different impact speeds and impact head qualities.The results of the ice impact test verify the feasibility of the test equipment and test technology,and at the same time show that the large cross-section ice sample is less damaged after being impacted,but bears a greater impact load.The shape of the impact head is an important factor affecting the destruction of ice samples.When the impact kinetic energy is consistent with the size of the sample,the more severe the damage of the sample caused by the shape,the smaller the impact load will be.For the same type of impact head,when the impact velocity is small,the ice sample has no obvious damage,and the impact load increases with the increase of impact velocity;when the impact velocity is high,the ice sample is obviously damaged,and the impact load increases with the increase in velocity.The drop-weight impact test shows that with the increase of speed and mass,the damage caused by the drop-weight impact test to the ice surface becomes more serious;the in-situ pendulum impact test results show that the impact resistance of floating ice is weaker than that of solid ice.The impact load of is also smaller than that of consolidated ice,and the corresponding impact damage forms of the two modes of ice samples are very different.Floating ice will cause very serious damage,and the corresponding impact load is not obvious with the increase of the impact head size.The ice impact test and on-site in-situ test conducted in this paper analyze the relevant parameters of ice impact under different conditions,such as load and failure mode.The experimental research breaks through the limitations of traditional material testing machines in terms of strain rate,etc.The comparison of the actual reduction ship-ice actual collision process is of great significance for studying the mechanism and related properties of ice impact damage.