準静的インデンテーションによる氷の変形および破壊現象の計測

抄録

Breaking ice with an ice pick is known as one of the ice fracture phenomena. In the previous study, we carried out the percussion test of the ice specimen using the conical and spherical indenter. It has been shown that the indenter shape had an influence on the energy required to fracture ice. In this study, the quasi-static indentation test was performed in a low-temperature environment using a chamber and a cooling system in order to investigate the fundamental deformation and fracture phenomena of ice. The conical indenter of 90° was used. The indentation rate was changed to set to three of 0.02, 0.2, and 2 mm/s. The test was conducted after keeping the temperature in the chamber at 10±1℃ for 360 s. The load-displacement relationship of ice during deformation increased and decreased due to crack formation. When the indentation rate was high, it was observed that the ice pieces were spattered during deformation, but not when the indentation rate was low. It was suggested that the deformation process of ice was changed from melting by friction and pressure to crack formation when the indentation rate was increased. In addition, it was shown that the maximum load, which means fracture load, decreased with increasing the indentation rate.