Intensive development of computer simulation technique for ice deformation and failure processes is an important problem in respect to both ice propulsion definition and strength analysis for ice vessel and ice-resistant structures. However, evaluation of applied algorithms effectiveness requires developing a procedure for verification of numerical models. This paper presents results of experiment-calculated studies for strains in a bounded region on a specimen surface containing a point grid. Grid movement during the tests was recorded with the help of a system of three-dimensional computer vision and digital image correlation for noncontacting shape and deformation measurements. An experimental facility, test methodology, observed results and test results processing method are explained. Experimental data on freshwater field ice under uniaxial compression and bending are given. Ice mechanical characteristics were evaluated based on inverse solution and finding ice strain characteristics as initial data for the finite element analysis. The calculated results were analyzed and compared with experimental data. Application of the proposed methodology will extend essentially a verification base for computer simulation of ice failure under contact with a structure and create prerequisites for forming a new direction in the area of ice numerical simulation.

Fundamentals of the similarity theory in the ice deformation mechanics, as well as problems related to scaling up of local ice pressures measured during tests in an ice basin to full scale values are considered. A new scaling principle based on a hypothesis of ice deformation limiting surface isomorphism and direct computer simulation is proposed. An ice-resistant platform, for which local pressures were measured in ice tests and ice pressures were recalculated to full scale values using generated ice deformation limiting surfaces, was considered as an example.

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At the present time design values of ice loads on fixed offshore structures are rather conservative. Conservatism of design ice loads consists in assuming the most unfavorable ice action direction and the worst ice drift speed; the most unfavorable combination of the consolidated layer thickness, ridge keel depth and ice strength; as well as supposing the ice ultimate strength value constant along the whole ice–structure contact area perimeter. With accumulation of the knowledge on ice formation failure under interaction with ice-resistant fixed platforms, the requirements contained in Rules of classification societies are reduced. For example, for the last forty years the lowering of requirements to design ice load values was equal to about four times [1]. For the last time specialists of Krylov State Research Centre have performed design and experimental studies where further tendency to decreasing design values of ice loads is traced. Ice monitoring is one of the main elements for justification of design ice load values’ decrease. Modern monitoring systems permit to warn about occurrence of a state close to a limit one, as well as to record actual ice loads. Ice load monitoring is a necessary part of accident prevention during ice-resistant structures operation. Monitoring of ice loads is a necessary part for providing safe operation of ice-resistance structures, and systematic accumulation of monitoring data for several years gives a positive effect in the form of justified decrease of static and dynamic design ice loads.