Development of methods for calculating the ice load on marine hydraulic structures in conditions of stable land fast ice

Despite the success of previous studies, there are still no reliable and accurate methods for determining the ice load on marine hydraulic structures (HS), taking into account the mechanical properties of ice and the characteristics of the ice situation. The object of the field study was the closed Sharapov Shar Bay in the Kara Sea, the ice situation of which is characterized by the presence of a stable land fast ice with a flat ice field. The subject of the study was the ice load in closed bays that have a stable land fast ice throughout the entire period of maximum ice impacts. The conditions of the bay provide viscoplastic  deformation  of  the  ice,  and  a  stable  land  fast  ice  will  deform  around  the  HS  in  a  state of prolonged creep without accumulation of cracks and damage. A method for determining ice loads has been developed, taking into account the features of a stable land fast ice. Ice loads on the HS should be determined on the basis of initial data on the nature of the ice situation in the HS construction area for the period of maximum ice loads. When determining the global load from flat ice on an extended structure with a vertical front wall for the conditions of Sharapov Shar Bay in April, when the maximum load from a stable land fast ice is observed, it is recommended to take the value of the correction factor kv =0.055. The calculated ice load on the HS should be taken as the maximum of all loads for the considered phase  of  the  ice  regime.  Provided  that  the  viscoplastic  deformations  of  ice  are  taken  into  account, the calculated load on the HS is the load when breaking the soldered ice, exceeding the value that occurs during the viscoplastic operation of ice in conditions of stable land fast ice. The practical implementation of  the  proposed  method  is  possible  only  after  the  relevant  methodological  requirements  are  included in  the  current  regulatory  documents.  The  use  of  current  regulatory  requirements  in  determining the calculated ice load does not allow to justify the use of gravity HS for the conditions of the Sharapov Shar Bay. And the proposed approach to the assessment of the ice load, taking into account the peculiarities of the phases of the ice regime and the transients between them, allowed us to justify the possibility of using a gravitational HS.

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