On the flexural strength of DUT-1 synthetic model ice

Based on the statistical values of Bohai ice physical and mechanical parameters—such as density, compressive strength, flexural strength, shear strength, elastic modulus and friction coefficient—an ideal synthetic model ice was designed following the scale of 1:10–1:30. A model ice prescription and making art were found and called DUT-1 Ice. In order to know the flexural strength of DUT-1 Ice in detail, two stages of experiment were arranged. During the first stage, over 500 samples for a series of systematic tests were done. It is found that ductile bending occurs below 350–400 kPa/s in three-point bend test and 60–65 kPa/s in cantilever bend test. Their corresponding failure time are in the range of 0.03–0.38 s and 0.5–0.76 s, respectively, which is in the range of flexural failure time of simulated natural ice. Comparison of flexural strength of downward and upward loading cantilever tests gives the affirmation of isotropy of the model ice because of its granular structure. After 1 h wetting, the peak flexural strength of three-point specimens becomes steady and maintains this state for more than 4 h. This period gives us enough time to conduct model tests of ice behaviors or ice interactions with structures. In the second stage, another 500 specimens was tested. The effects of cement content and curing period were obtained, and the selection method of suitable peak flexural strength for different ices and test scale can be done based on the effects. Similar with natural ice, DUT-1 Ice flexural strength increases with increased wetted density. The ratio of elastic modulus and flexural strength over 2000 indicated that DUT-1 Ice is capable of physical simulations of ice bending failures with inclined structures, with waves, ice pile-up and ice jam processes.