Research And Application Of Artificial Ice Failure Criteria In Ice Rink

The National Aquatics Center will be transformed into the venue for Olympic curling and wheelchair curling during the 2022 Winter Olympics in Beijing.As an ice rink undertaking international curling competition,its artificial ice surface should not only meet the requirements of stiffness and bearing capacity,but also ensure that the vibration and deformation of the ground will not affect the normal slide of curling on the ice surface.Up to now,the international ice sports organizations have not put forward definite mechanical property indexes and strength failure criteria of ice used in the field.Therefore,it is necessary to conduct further research on the mechanical properties of artificial ice in the rink.In this paper,the compressive performance,shear performance and strength failure criterion of the artificial ice in the ice rink were studied,and the mechanical properties of the artificial ice surface under different loads were systematically analyzed.The self-designed low-temperature test chamber ice making tank was used to prepare artificial ice,and the stress performance of the tank under different working conditions was analyzed by finite element method to verify whether its bearing capacity and deformation meet the test requirements.Through the preparation and observation of ice slices,the crystal structure type of artificial ice was determined,and the variation of ice grain size with ice slab thickness and ice temperature was analyzed.At the same time,the average density of ice was measured.Strain rate,ice temperature,ice making method,water quality TDS,room temperature and humidity were selected as test conditions to carry out uniaxial compressive strength test of artificial ice on ice rink.According to the test results,the typical stress-strain curves and failure modes of ice samples under uniaxial compression are given,and the qualitative relationships between uniaxial compression strength,equivalent elastic modulus and various influencing factors are obtained.Meanwhile,the quantitative mathematical expressions of uniaxial compression strength,elastic modulus,strain rate and ice temperature of artificial ice are established by regression analysis.In order to further explore the mechanical constitutive relationship of artificial ice in ice rink,the triaxial compressive strength of artificial ice samples under different ice temperature and confining pressure was studied.According to the test results,the typical stress-strain curves and failure modes of ice samples under triaxial condition are given,and the quantitative relationship between ice shear strength and confining pressure and ice temperature is obtained.Mohr Coulomb strength theory and D-A failure theory are used to establish the strength failure criteria of artificial ice on ice rink,and the fitting results of the two failure criteria are compared.The triaxial compressive strength test of artificial ice on ice rink was simulated by using the ice mechanics parameters obtained from indoor test;According to the actual stress conditions of ice rink,the mechanical properties of assembled ice rink and simplified ice rink under different loads are simulated and analyzed to determine the ultimate bearing capacity and failure mode of ice rink;The multi-scale analysis method is used to establish the refined model of the assembly ice rink,and analyze the influence of the ice shelf and ice pipe on the mechanical performance of the ice surface.