Reports at the international conference «ISOPE 2021»

On June 20 the international conference ISOPE-2021 (The International Society of Ocean and Polar Engineers, a conference of the International Community of Marine and Polar Engineers) began. This year, the conference is held online and will last until June 25, 2021. Three works of the Laboratory of Ice Engineering Research Fundamentals staff members will be presented at the conference:

Autoregressive Model for Ice Loads Registered in Slow-speed Indentation Tests

Head of the Research Laboratory "Ice Engineering Research Fundamentals", Candidate of Technical Sciences, P. N. Zvyagin

ABSTRACT

The paper considers the loads measured in indentation tests with cylindrical indenters 40 mm in diameter at 1 mm/s velocity. The common linear-like part of load growth within first 1.75 sec of the contact is revealed. An alternative autoregressive model of unit root for the load in this part is applied. The paper shows that adjustment of autoregressive model with Gaussian residuals may be used for localizing the beginning of ice-indenter interaction in raw ice load time series.

KEY WORDS: Model ice, ice load, indentation test, unit root

On the Main Factors in Ice Rubble Pile Development Against the Sloped structure

Leading Research Fellow of the Laboratory of Ice Engineering Research Fundamentals", Doctor of Technical Science, K. E. Sazonov; engineer of the Laboratory of Ice Engineering Research Fundamentals A. A. Simakina

ABSTRACT The paper considers the main factors influencing the height of ice rubble pile formed during the interaction of ice and an inclined structure. The main factors determining the development of ice rubble pile against an obstacle are presented. The article suggests the mechanisms of destruction of ice cover with a pile-up upon contact with a structure of various inclination angles. For an inclination angle lying between two extreme events (horizontal and vertical walls), the maximum height of ice rubble pile causing destruction of ice cover was estimated. The models of free-flowing media are considered to describe shifting of a pile-up along a certain surface, including the surface of the structure. The paper studies the mechanism of ice rubble pile stability loss and the process of partial overhanging of destroyed ice outside the structure. It is demonstrated that loss of stability is one of the main factors limiting the height of ice rubble pile.

KEY WORDS: ice rubble pile, ice bending, ice destruction, loss of stability, pile-up height, inclined structure.

The Model of an Ice Plate with Fixed-Ends Failure by Vertical and Horizontal Loads

Engineer of the Laboratory of Ice Engineering Research Fundamentals A. A. Simakina, engineer of the Laboratory of Ice Engineering Research Fundamentals M. A. Drepin

ABSTRACT The paper considers a model of interaction between a fixed-end ice plate and an inclined structure. Previously, the problem had been solved in the formulation with failure of ice under the action of either vertical or a horizontal load. This paper presents the equations for calculating the deflection and stresses in a fixed-end ice plate, as well as their numerical analysis when loads are applied to the center of the plate in two perpendicular directions. The article analyzes how the angle of inclination of a structure and proportion of the length and the width of an ice plate contribute to the maximum stresses created by the vertical and horizontal loads. KEY WORDS: ice bending, ice-failure, inclined structure, fixed-end plate