The Coefficient of Friction Between Sea Ice and Various Materials Used in Offshore Structures

Abstract

When structures having inclined surfaces, such as cone-type and inclined-pile structures, are constructed in coastal and offshore cold regions, sea ice forces must be considered in their design. In order to estimate these forces, the relationships of the coefficients of static and kinetic friction between sea ice and construction materials must be evaluated. The authors have been conducting, for four years, experiments on the coefficients of friction between sea ice and various commonly used offshore construction materials such as concrete and steel. This paper summarizes the results of this study. The coefficients of friction have been found to be affected by the following: (i) relative velocity (i.e., velocity of construction material relative to sea ice); (ii) sea ice temperature; and (iii) surface roughness of construction material. They have been found to be relatively unaffected by the following: (i) contact area, (ii) normal stress, (iii) growth direction of sea ice, and (iv) water at the sea ice-material interface.

The friction of ice on ice at low sliding velocities

“…Third, as in our experiments, Saeki et al (1986) observed no e ect of pressure over the range 0.1± 1 MPa on the sea-ice± steel friction coe cient at ¡38C at 1104…”

In Situ Experimental Study of the Friction of Sea Ice and Steel on Sea Ice

“…One reason is that steel, coated steel, and natural ice normally have different surface roughnesses. A portion of the friction force can be attributed to the substantial surface adhesion occurring within the real contact area of the surface asperities [23], and therefore, the scatter was partly caused by the different surface roughnesses of the contact materials [29]. However, the surface of nature ice cover was not absolutely flat, and the scales of the bumps were larger than the surface roughness.…”

“…The pure effect of the surface roughness might be covered by the bumps and was beyond the scope of the current study. The role of microcosmic surface characterization has been investigated in several previous laboratory studies using well-prepared samples [23,25,29]. …”

“…Therefore, a detailed study on the effect of surface roughness on µ k is beyond the scope of the current work, which can be investigated in laboratory using well-prepared ice samples. Saeki et al [29] conducted the surface analysis on three kinds of concrete and four kinds of steel plates using a high-accuracy surface roughness meter and pulled them on ice samples. Their results showed that the friction coefficient had no apparent correlation with wavelength of irregularities, but increased with increasing mean wave height and mean steepness and with decreasing mean sharpness.…”

“…To understand the behavior of ice friction, laboratory experiments have been conducted on the friction of ice against ice [21][22][23][24][25], against metals [26,27], against coatings [28,29], against polymethyl methacrylate [30,31], against glass [32], and against rubber [33]. Several impact factors have been investigated, such as sliding velocity, temperature, normal load, and grain structure.…”