A series of ice indentation tests have been performed since the 1996 winter at Lake Notoro in Hokkaido, Japan (JOIA reports; 1996, 1997,1998 and 1999), as part of the JOIA project. The main factors affecting total ice load iF) on a structure were investigated using data derived under systematic test conditions, using natural sea ice. The width (W) of the model structure, ice thickness (h), indentation speed iV) and uni-axial compressive strength (ac) are the major factors influencing ice load on a slructure with a vertical face. The paper determines the dependence of (W/h), (V/h) and (h) on indentation pressure (Pt). It also describes the pressure distribution examined by the 2-dimensional panel sensor, which can measure pressures in 2112 points at once, depending on various indentation speeds.
The JOIA project has been in progress since 1995 to determine the scaling effect of ice load. In medium-scale field indentation tests (MSFIT), as a part of the project, a lot of local ice load data as well as total ice load data were obtained through load cells attached to a 100mm-wide-surface-panel of a model structure in contact with an ice sheet. In the 1998 winter, a 2-dimensional panel sensor that can measure pressures of around 1936 points (44-row*44-columm) per panel (smaller panel) was also used to determine the ice failure pattern in addition to local ice pressures. These results were reported in Takeuchi et.al,1997, 1998 & 1999; Saeki et al., 1998; and Sodhi et al., 1998. Width (W) of the model structure, ice thickness (h) and indentation speed iV) were varied as main parameters influencing total ice load and ice failure mode in the test series. In particular, in the 1999 winter tests, thicker ice and a wider range of indentation speeds were considered