Study Of Ice Mechanical Properties Parameters Based On Ultrasonic Wave

This project is an basic research aimed at the ice mechanical properties parameters,which is funded by National Youth Fund “ The study on mechanism and method of In-situ monitoring of porosity in sea ice profile based on ultrasonic wave”(ID: 41606220).The Bohai Sea and the northern part of the Yellow Sea will occur severe freezing in the particularly cold winters.A large amount of sea ice causes the sea traffic to be interrupted,and the offshore oil platform is damaged,which causes serious economic losses.With the rapid rise of global temperature,the interaction between polar sea ice and the atmosphere and ocean is more obvious.Compared with Arctic sea ice,the Antarctic sea ice conclusion is far from deep due to observation data is scarce.Therefore,it is necessary to monitor the ice mechanical performance parameters of sea ice,which can provide reference data for the collision of offshore sea ice on oil rigs and the ability of ship icebreaking,and provide basic data for the correlation between polar sea ice changes and climate change in China.In addition,the erosion of the ice in the winter of thenorthern part of the reservoir in China is serious.For the hydraulic structure design in the cold area,the force of the ice row on the structure is an important control load,the compression strength of ice is the key parameter for load calculation.Therefore,it is necessary to monitor the ice mechanical properties of river ice and lake ice,which can provide basis for the anti-ice calculation of reservoir engineering and river slope protection engineering.In this paper,the ice mechanical properties of freshwater ice and sea ice were studied by ultrasonic wave.This paper include low frequency ultrasonic vave attenuation experimental system research,high frequency ultrasonic wave ice mechanical performance parameter research and ice mechanics parameter judgment algorithm research based ultrasonic wave three parts.The research of low-frequency ultrasonic attenuation experiment mainly introduces the selection of ultrasonic transducer,the composition and test process of low-frequency ultrasonic attenuation experimental system,and analyzes the experimental results.The low-frequency ultrasonic attenuation experiment is a pre-experiment of the high-frequency ultrasonic ice mechanical performance parameter detection experiment,which shows that the attenuation of the ultrasonic amplitude in ice is regular at different temperatures.It can provide a certain experimental basis for further study of high frequency ultrasound related experiments in ice.The study of high-frequency ultrasonic ice mechanical properties parameters includes two parts: ice mechanical performance parameters andultrasonic amplitude attenuation studies.In this study,a non-linear high-energy ultrasonic test system was used to measure freshwater ice samples and sea ice ice samples,and the gradual cooling process and the gradual heating process were analyzed.The ultrasonic transverse wave velocity,the ultrasonic longitudinal wave velocity,the ice mechanical properties parameters and the ultrasonic amplitude were varied at different temperatures.Ultrasonic-based ice mechanics parameter judgment algorithm is a study of the relationship between ice mechanics parameters and ultrasonic longitudinal wave amplitude.The research shows that the freshwater ice mechanical parameters have a one-to-one correspondence with the ultrasonic longitudinal wave amplitude,and the amplitude of the ultrasonic waves directly monitor and research relates to the ice mechanical parameters,which are theoretically feasible.That is to say,the ultrasonic amplitude monitoring sensor and its system for designing optimal parameters are studied.The method of real-time monitoring of ultrasonic amplitude is studied.It is feasible to realize the direct judgment of ice mechanical parameters through the relationship between ultrasonic amplitude and ice mechanical parameters.