Following Leggett and Gold dimensional variables defining ice-induced pressures on vertical structures (B, h, u, E, σ_f, K_(IC), ρ_i, g) were identified. Applying dimensional analysis, following Atkins, these dimensional variables were reduced to dimensionless dependent variable (ρ_e/ρ_iu~2) and a limited number of dimensionless independent parameters, namely aspect ratio (B/h), dimensionless velocity [u/(gh~(1/2))] and dimensionless material properties. A large number of experimental data from physical model tests and field tests, using different types of ice -freshwater ice, seawater ice, and model ice were analyzed, following rigorous requirements of dimensional analysis. (1) It was found that when other conditions remain same, dimensionless ice-induced pressure (ρ_e/ρ_iu~2) on rigid vertical structures decreases with (a) increasing aspect ratio (B/h), at a rate of about 0.42; (b) increasing dimensionless velocity or dimensionless strain-rate or thickness Froude number [u/(gh)~(1/2)] at a rate of about 1.80 when u/(gh)~(1/2) is < about 6.0×10~(3) and at a rate of about 1.93 when u/(gh)~(1/2) is > about 6.0×10~(3). (2) It was also found that shapes of structures do not influence dimensionless ice-induced pressures on structures. (3) Qualitative influence of material properties of ice has been identified, which shows that when other conditions, namely (B/h), and [u/(gh)~(1/2)], remain same, (ρ_e/ρ_iu~2) for sea-ice interaction is about 1.8 orders of magnitude less than that for freshwater ice interaction. Analyses to establish the exact influence of dimensionless material properties on dimensional ice-induced pressure quantitatively is in progress, completion of which will lead to development of an empirical relationship for dimensional ice-induced pressure on vertical structure.
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