EVALUATION OF SOIL RESPONSE IN THE BASE OF ENGINEERING STRUCTURES TO THE IMPACT OF BULK ICE FIELDS

The comprehensive assessment of possible degradation of soils under the influence of long-term cyclic load caused by the movement of ice fields included several stages. First, the procedure of calculating the expected parameters of the amplitude-frequency spectrum of impacts and the corresponding shear forces was performed. In the course of experiments using the calculated parameters and loads, the so-called Wohler curves characterizing the change in the strength of dispersed soils under cyclic influences were obtained. The following factors control the decrease in strength: the cyclic nature of loading, its amplitude and duration; whereas, its mechanism consists in the possible redistribution of stress between the mineral skeleton and the pore water. The final analysis of soil behavior was completed taking into account the cyclic ice load in winter period of the accepted duration. The results of soil-stability assessment in the ground base at the site in the northern part of the Caspian Sea shelf are presented.